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As filed with the ~~U.S.~~ Securities and Exchange Commission on ~~September 11~~May 8, ~~2019~~ 2026

Registration No. 333-

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM S-1 ~~REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933~~

~~VAXART, INC.~~REGISTRATION STATEMENT ~~(Exact~~UNDER ~~name of registrant as specified in its charter)~~

~~Delaware~~THE ~~(State~~SECURITIES orACT ~~other~~OF ~~jurisdiction of incorporation or organization) 2834 (Primary Standard Industrial Classification Code Number) 59-1212264 (I.R.S. Employer Identification No.)~~1933

~~290 Utah Ave Suite 200 South San Francisco~~VAXART, ~~California 94080 (650) 550-3500 (Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)~~ INC.

~~Wouter W. Latour M.D. President and Chief Executive Officer 290 Utah Ave Suite 200 South San Francisco, California 94080~~ (~~650) 550-3500 (Name,~~Exact ~~address,~~name ~~including~~of ~~zip~~registrant ~~code,~~as ~~and~~specified ~~telephone~~in ~~number,~~its ~~including area code, of agent for service~~charter)

~~Copies~~ ~~to:~~Delaware ~~John~~(State T.or ~~McKenna~~other ~~Josh~~jurisdiction ~~Seidenfeld~~of ~~Cooley~~incorporation ~~LLP~~or ~~3175~~organization) ~~Hanover~~ ~~Street~~2836 ~~Palo Alto, California 94304~~ (~~650)~~Primary ~~843-5000~~Standard ~~Gary~~Industrial ~~Emmanuel~~Classification ~~Heidi~~Code ~~Steele~~Number) ~~McDermott~~ ~~Will~~59-1212264 &(I.R.S. ~~Emery~~Employer ~~LLP~~Identification ~~340 Madison Avenue New York, New York 10173 (212~~Number) ~~547-5400~~

~~Approximate~~310 ~~date~~Utah ofAvenue, ~~commencement~~Suite ~~of proposed sale to public: As soon as practicable after the effective date of this registration statement.~~ 150

IfSouth ~~any~~San ~~of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933~~Francisco, asCA ~~amended,~~94080 ~~check the following box: ý~~ (650) 550-3500

~~If this Form is filed to register additional securities for an offering pursuant to Rule 462~~(b)Address, ~~under~~including ~~the~~zip ~~Securities Act~~code, ~~please check the following box~~ and ~~list~~telephone ~~the~~number, ~~Securities~~including ~~Act~~area ~~registration~~code, ~~statement number~~ of ~~the~~registrant’s ~~earlier~~principal ~~effective~~executive ~~Registration Statement for the same offering: o~~ offices)

IfSteven this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, please check the following box and list the Securities Act Registration Statement number of the earlier effective Registration Statement for the same offering: o Lo

IfChief ~~this~~Executive Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act Registration Statement number of the earlier effective Registration Statement for the same offering: o Officer

~~Indicate~~310 byUtah ~~check mark whether the registrant is a large accelerated filer~~Avenue, anSuite accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act. 150

~~Large~~South ~~accelerated~~San ~~filer~~Francisco, oCA ~~Accelerated filer o Non-accelerated filer ý Smaller reporting company ý Emerging growth company o~~94080

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a650)~~(2)(B)~~ ~~of the Securities Act of 1933, as amended. o~~ 550-3500

~~CALCULATION~~(Name, OFaddress, ~~REGISTRATION~~including ~~FEE~~ zip code, and telephone number, including area code, of agent for service)

Title of Each Class of Securities to be Registered	Proposed Maximum Aggregate Offering Price(1)	Amount of Registration Fee(1)
Common stock, par value $0.10 per share	$(2)
Pre-funded warrants to purchase shares of common stock and common stock issuable upon exercise thereof	$(3)
Common warrants to purchase shares of common stock and common stock issuable upon exercise thereof	$(2)
Representative warrants to purchase shares of common stock and common stock issuable upon exercise thereof	$(4)
Total	$11,500,000(5)	$1,394

Copies to:

~~The~~Faith ~~Registrant~~L. ~~hereby~~Charles ~~amends~~Thompson ~~this~~Hine Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment that specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine. LLP

300 Madison Avenue, 27th Floor

New York, NY 10017

(212) 908-3905

Approximate date of commencement of proposed sale to the public:

As soon as practicable after the effective date of this registration statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer	☐	Accelerated filer	☒
Non-accelerated filer	☐	Smaller reporting company	☒
		Emerging Growth Company	☐

THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF THE SECURITIES ACT OF 1933, AS AMENDED, OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE SECURITIES AND EXCHANGE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(a), MAY DETERMINE.

Table of Contents

~~The~~THE ~~information~~INFORMATION inIN ~~this~~THIS ~~preliminary~~PROSPECTUS ~~prospectus~~IS isNOT ~~not~~COMPLETE ~~complete~~AND ~~and~~MAY ~~may~~BE ~~be changed~~CHANGED. WeTHE ~~may~~SELLING ~~not~~STOCKHOLDER ~~sell~~MAY ~~these~~NOT ~~securities~~RESELL orTHESE ~~accept~~SECURITIES anUNTIL ~~offer~~THE toREGISTRATION ~~buy~~STATEMENT ~~these~~FILED ~~securities until~~WITH ~~the~~THE ~~registration~~SECURITIES ~~statement~~AND ~~filed~~EXCHANGE ~~with~~COMMISSION ~~the~~IS ~~Securities~~DECLARED ~~and Exchange Commission is effective~~EFFECTIVE. ~~This~~THIS ~~preliminary~~PROSPECTUS ~~prospectus~~IS isNOT ~~not~~AN anOFFER ~~offer~~TO toSELL ~~sell~~THESE ~~these~~SECURITIES ~~securities~~AND ~~and~~IS itNOT isSOLICITING ~~not~~AN ~~soliciting~~OFFER ~~offers~~TO ~~to buy~~BUY ~~these~~THESE ~~securities~~SECURITIES inIN ~~any~~ANY ~~state~~STATE ~~where~~WHERE ~~such~~THE ~~offer~~OFFER orOR ~~sale~~SALE isIS ~~not~~NOT ~~permitted~~PERMITTED.

PRELIMINARY PROSPECTUS ~~SUBJECT TO COMPLETION, DATED SEPTEMBER 11, 2019~~

~~Shares~~SUBJECT ofTO ~~Common~~COMPLETION ~~Stock~~ DATED May 7, 2026

32,914,599 ~~Pre-Funded Warrants to Purchase~~ Shares of Common Stock

Vaxart, ~~Common Warrants to Purchase Shares of Common Stock~~ Inc.

WeThis ~~are~~prospectus ~~offering~~relates up to ~~shares~~ ~~of our common stock and common warrants to purchase an aggregate of shares of our common stock (and~~ the ~~shares~~offer of common stock that are issuable from time to time upon exercise of the common warrants). We are also offering to certain purchasers whose purchase of shares of common stock in this offering would otherwise result in the purchaser, together with its affiliates and ~~certain~~resale ~~related parties, beneficially owning more than 4.99% (or, at the election~~ of ~~the~~up ~~purchaser, 9.99%) of our outstanding common stock immediately following the consummation of this offering, the opportunity~~ to ~~purchase~~32, ~~if any such purchaser so chooses~~914,599 ~~pre-funded warrants, in lieu of~~ shares of ~~common~~ ~~stock that would otherwise result in such purchaser's beneficial ownership exceeding 4.99% (or, at the election of the purchaser, 9.99%) of~~ our ~~outstanding~~ common stock. ~~Each pre-funded warrant will be exercisable for one share of our common stock and will be accompanied~~ by aLincoln ~~common~~Park ~~warrant~~Capital ~~to purchase one share of common stock. The purchase price of each pre-funded warrant will be equal to the price at which a share of common stock is sold to the public in this offering~~Fund, ~~minus $0.10~~LLC, ~~and~~which ~~the~~we ~~exercise~~refer price of each pre-funded warrant will be $0.10 per share. The pre-funded warrants will be immediately exercisable and may be exercised at any time until all of the pre-funded warrants are exercised in full. This offering also relates to ~~the shares of common stock issuable upon exercise of the common warrants and any pre-funded warrants sold~~ in this ~~offering.~~prospectus For each pre-funded warrant we sell, the number of shares of common stock we are offering will be decreased on a one-for-one basis. Therefore the number of common warrants sold in this offering will not change as a“Lincoln ~~result~~Park” ofor ~~a change in~~ the ~~mix~~“selling ~~of the shares of our common stock and pre-funded warrants sold~~stockholder. The common warrants will be exercisable immediately and will expire five years from the date of issuance. The shares of common stock and pre-funded warrants, and the accompanying common warrants, can only be purchased together in this offering but will be issued separately and will be immediately separable upon issuance. Our common stock is listed on the Nasdaq Capital Market under the symbol "VXRT." On September 10, 2019, the last reported sale price of our common stock was $0.75 per share. The actual public offering price per share of common stock and any pre-funded warrant will be determined between us and the underwriters at the time of pricing, and may be at a discount to the current market price. Therefore, the assumed public offering price used throughout this prospectus may not be indicative of the final offering price. There is no established public trading market for the pre-funded warrants and the common warrants, and we do not expect a market to develop. In addition, we do not intend to apply for a listing of the pre-funded warrants and the common warrants on any national securities exchange or other nationally recognized trading system. ”

~~Investing~~The inshares ~~our securities involves a high degree~~ of ~~risk.~~common ~~You~~stock ~~should~~being ~~carefully~~offered ~~read~~by ~~and consider~~ the ~~"Risk~~selling ~~Factors" beginning~~stockholder onconsist ~~page 11~~ of ~~this prospectus before investing.~~:

~~Neither~~• up ~~the~~to ~~Securities~~32,467,532 shares of common stock that we may elect to issue and ~~Exchange~~sell ~~Commission~~to ~~nor~~Lincoln ~~any~~Park, ~~state~~in ~~securities~~our ~~commission~~sole ~~has~~discretion ~~approved~~from ortime ~~disapproved~~to oftime ~~these securities~~after orthe ~~passed~~date ~~upon~~of this prospectus (the ~~adequacy~~“Purchase orShares”), ~~accuracy~~pursuant to a purchase agreement, dated as of April 16, 2026, that we entered into with Lincoln Park, which we refer to in this prospectus. ~~Any~~as ~~representation~~the “Purchase Agreement”, providing for up to ~~the~~$25 ~~contrary~~million isof acommitted ~~criminal~~equity ~~offense.~~financing; and

	Per Share	Per Pre-Funded Warrant	Per Common Warrant	Total
Public offering price	$	$	$	$
Underwriting discounts and commissions(1)	$	$	$	$
Proceeds, before expenses, to us	$	$	$	$

• 447,067 shares of our common stock that we issued to Lincoln Park on April 16, 2026 as consideration for its irrevocable commitment to purchase our common stock pursuant to the Purchase Agreement (the “Commitment Shares”).

~~We have~~See ~~granted~~“The ~~the~~Lincoln ~~underwriters~~Park ~~the~~Transaction” ~~right~~for todescriptions ~~purchase up to additional shares~~ of ~~our common stock and/or common warrants to purchase up to an aggregate of an additional shares of common stock, in each case at~~ the ~~public~~Purchase ~~offering~~Agreement ~~price, less underwriting discounts~~ and ~~commissions.~~“Selling ~~The~~Stockholder” ~~underwriters~~for ~~can exercise this right at any time within 30 days from the date of this prospectus. If the underwriters exercise their option to purchase~~ additional ~~shares~~information ~~and/or~~regarding ~~common~~Lincoln warrants in full, the total underwriting discounts and commissions payable by us will be $ and the total proceeds to us from this offering, before expenses, will be $ , excluding the proceeds, if any, from the exercise of the pre-funded warrants and common warrantsPark.

We ~~anticipate~~ ~~that~~are ~~delivery~~not selling any securities under this prospectus and will not receive any of the proceeds from the resale by the selling stockholder of shares of common stock under this prospectus. However, we may receive proceeds of up to $25 million from our sale of Purchase Shares, if any, ~~pre-funded~~to ~~warrants~~Lincoln Park under the Purchase Agreement, from time to time in our discretion after the date the registration statement of which this prospectus is a part is declared effective and ~~accompanying~~the ~~common~~other ~~warrants~~conditions ~~will~~in bethe ~~made~~Purchase onAgreement orhave ~~about , 2019.~~been satisfied.

~~Sole~~Lincoln ~~Book-Running~~Park ~~Manager~~may sell the shares of our common stock described in this prospectus in a number of different ways and at varying prices. The price that Lincoln Park will pay for the shares to be resold pursuant to this prospectus will depend upon the timing of sales and will fluctuate based on the trading price of our common stock. Lincoln Park is an “underwriter” within the meaning of Section 2(a)(11) of the Securities Act of 1933, as amended (the “Securities Act”).

HThe purchase price for the Purchase Shares will be based upon formulas set forth in the Purchase Agreement and described in this prospectus depending on the type of purchase notice we submit to Lincoln Park from time to time.C We will pay the expenses incurred in registering the shares of our common stock, including legal and accounting fees. ~~Wainwright~~See “Plan of Distribution” beginning on page 130 ~~& Co~~for more information about how Lincoln Park may sell the shares of common stock being registered pursuant to this prospectus.

~~Manager~~ Our common stock is quoted on the OTCQX® Best Market (the “OTC”) under the symbol “VXRT.” On May 7, 2026, the closing price per share of our common stock on the OTC was $0.74.

~~Brookline~~Investing ~~Capital~~in ~~Markets~~ our common stock is highly speculative and involves a significant degree of risk. Please consider carefully the specific factors set forth under “Risk Factors” beginning on page 4 of this prospectus and in our filings with the Securities and Exchange Commission.

~~The~~Neither ~~date~~the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is , ~~2019~~truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is , 2026.

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TABLE OF CONTENTS


	Page
Prospectus Summary		1
ABOUT THIS PROSPECTUS	1
The Offering		6
PROSPECTUS SUMMARY	2
Risk Factors		11
THE OFFERING	3
Special Note Regarding Forward-Looking Statements		14
RISK FACTORS	4
Market and Industry Data		16
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	59
Use of Proceeds		17
OUR AGREEMENTS WITH LINCOLN PARK	60
Dividend Policy		18
USE OF PROCEEDS	66
Capitalization		19
MARKET FOR COMMON STOCK AND DIVIDEND POLICY	67
Dilution		21
DESCRIPTION OF BUSINESS	68
Principal Stockholders		23
MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS	92
Description of Capital Stock		26
MANAGEMENT	108
Description of Securities We Are Offering		29
EXECUTIVE COMPENSATION	118
Underwriting		32
SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT	125
Material U.S. Federal Income Tax Consequences		36
CERTAIN RELATIONSHIP AND RELATED PARTY TRANSACTIONS	127
Legal Matters		43
SELLING STOCKHOLDER	128
Experts		43
PLAN OF DISTRIBUTION	130
Where You Can Find More Information		44
DESCRIPTION OF OUR SECURITIES TO BE REGISTERED	132
Incorporation of Certain Information by Reference		45
LEGAL MATTERS	133
EXPERTS	133
WHERE YOU CAN FIND MORE INFORMATION	133
INDEX TO CONSOLIDATED FINANCIAL STATEMENTS	F-1

We and the underwriters have not authorized anyone to provide any information or to make any representations other than those contained in or incorporated by reference in this prospectus or in any free writing prospectuses prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus is an offer to sell only the shares offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. The information contained in or incorporated by reference in this prospectus is accurate only as of its date regardless of the time of delivery of this prospectus or of any sale of common stock or pre-funded warrants and accompanying common warrants.

Neither we nor the underwriters have done anything that would permit this offering or possession or distribution of this prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons who come into possession of this prospectus and any free writing prospectus in jurisdictions outside the United States are required to inform themselves about and to observe any restrictions as to this offering and the distribution of this prospectus and any free writing prospectus applicable to that jurisdiction.

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Table ~~PROSPECTUS~~of ~~SUMMARY~~ Contents

~~This~~ABOUT ~~summary~~THIS highlights certain information about us, this offering and selected information contained elsewhere in this prospectus and in the documents incorporated by reference. This summary is not complete and does not contain all of the information that you should consider before deciding whether to invest in our securities. For a more complete understanding of our company and this offering, we encourage you to read and consider carefully the more detailed information contained in or incorporated by reference in this prospectus, including the information contained under the heading "Risk Factors" beginning on pagePROSPECTUS ~~11 of this prospectus, and the information included in any free writing prospectus that we have authorized for use in connection with this offering.~~

~~Throughout~~The registration statement we filed with the Securities and Exchange Commission (the “SEC”) includes exhibits that provide more detail of the matters discussed in this prospectus. You should read this prospectus, the ~~terms~~related ~~"we~~exhibits filed with the SEC. You should rely only on the information provided in this prospectus or any amendment thereto. In addition," ~~"us~~this prospectus contains summaries of certain provisions contained in some of the documents described herein," ~~"our~~but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed," ~~and~~will ~~"our~~be ~~company"~~filed ~~refer~~or will be incorporated by reference as exhibits to ~~Vaxart~~the registration statement of which this prospectus is a part, ~~Inc~~ and you may obtain copies of those documents as described below under the heading “Where You Can Find More Information.”

~~Overview~~ The selling stockholder named in this prospectus may sell up to 32,467,532 shares of our common stock previously issued and issuable pursuant to the Purchase Agreement from time to time. This prospectus also covers any shares of common stock that may become issuable as a result of share splits, share dividends, or similar transactions. We have agreed to pay the expenses incurred in registering these shares, including legal and accounting fees.

We ~~are~~have anot, ~~clinical-stage~~and ~~biotechnology~~the ~~company~~selling ~~focused~~stockholder onhas ~~the~~not, ~~development~~authorized ofanyone ~~oral~~to ~~recombinant~~provide ~~vaccines~~any ~~based~~information onor ~~our~~to ~~proprietary~~make ~~oral~~any ~~vaccine platform.~~representations ~~Our~~other ~~oral~~than ~~vaccines~~those ~~are~~contained ~~designed~~in tothis ~~generate~~prospectus ~~broad~~or ~~and~~in ~~durable~~any ~~immune~~free ~~responses~~writing ~~that~~prospectuses ~~protect~~prepared ~~against~~by aor ~~wide~~on ~~range~~behalf of ~~infectious~~us ~~diseases~~or ~~and~~to ~~may~~which bewe ~~useful~~have referred you. We take no responsibility for, and can provide no assurance as to the ~~treatment~~reliability of, ~~chronic~~any ~~viral infections~~other ~~and~~information ~~cancer~~that others may give you. ~~Our~~The ~~vaccines~~information ~~are~~contained ~~administered~~in ~~using~~this aprospectus ~~convenient~~or ~~room~~in ~~temperature-stable~~any ~~tablet~~applicable free writing prospectus is current only as of its date, ~~rather~~regardless ~~than~~of byits ~~injection~~time of delivery or any sale of our securities. Our business, financial condition, results of operations and prospects may have changed since that date.

~~We are~~The ~~developing~~selling ~~prophylactic~~stockholder ~~vaccine~~is ~~candidates~~offering ~~that~~to ~~target~~sell, aand ~~range~~seeking ofoffers ~~infectious~~to ~~diseases. These include norovirus~~buy, ashares ~~widespread cause~~ of ~~acute~~our ~~gastro-intestinal~~common ~~enteritis,~~stock ~~for~~only ~~which two~~under ~~Phase 1~~circumstances ~~human studies have been completed~~ and ain ~~third,~~jurisdictions ~~the~~where ~~Phase 1b~~it ~~bivalent study,~~ is ~~close~~lawful to ~~completion;~~do ~~seasonal~~so. ~~influenza,~~The ~~for~~selling ~~which~~stockholder ~~our~~is ~~vaccine~~not ~~protected~~making ~~patients~~an inoffer ato ~~recent Phase 2~~sell ~~challenge~~these ~~study;~~securities ~~and~~in ~~respiratory~~any ~~syncytial~~state ~~virus,~~ or ~~RSV,~~jurisdiction awhere ~~common~~the ~~cause~~offer ofor ~~respiratory~~sale ~~tract~~is ~~infections.~~not ~~In addition, we are developing our first therapeutic immune-oncology vaccine targeting cervical cancer and dysplasia caused by human papillomavirus, or HPV~~permitted.

~~Vaccines have~~Unless ~~been~~the ~~essential~~context inotherwise ~~eradicating or significantly reducing multiple devastating infectious diseases~~requires, ~~including polio~~“Vaxart,” ~~smallpox~~“VXRT,” ~~mumps,~~“the ~~measles~~Company,” ~~diphtheria~~“we,” ~~hepatitis B~~“us, ~~influenza,~~” ~~human~~“our” ~~papillomavirus~~ and ~~several~~similar ~~others.~~terms ~~According~~refer ~~a recent MarketsandMarkets research report "Vaccines Market—Global Forecast~~ to ~~2023"~~Vaxart, ~~the global market for vaccines is expected to reach $50~~Inc.~~42 billion by 2023 from $36.45 billion in 2018, at a compound annual growth rate of 6.7%.~~

We believe our oral tablet vaccine candidates offer several important advantages:

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~~Our~~PROSPECTUS ~~Product Pipeline~~ SUMMARY

The following ~~table~~is ~~outlines~~a summary of what we believe to be the ~~status~~most important aspects of our ~~oral~~business ~~vaccine~~and ~~development~~the ~~programs:~~offering of our securities under this prospectus. We urge you to read this entire prospectus, including the more detailed audited and unaudited financial statements, notes to the financial statements and other information from our other filings with the SEC or included in any applicable prospectus supplement. Investing in our securities involves risks. Therefore, carefully consider the risk factors set forth in any prospectus supplements and in our most recent annual and quarterly filings with the SEC, as well as other information in this prospectus and any prospectus supplements and the documents incorporated by reference herein or therein, before purchasing our securities. Each of the risk factors could adversely affect our business, operating results and financial condition, as well as adversely affect the value of an investment in our securities.

~~We are~~Our ~~developing the following tablet vaccine candidates, which are all based on our proprietary platform:~~ Company

~~Norovirus is~~We ~~the~~are ~~leading~~a ~~cause~~clinical-stage ofbiotechnology ~~vomiting~~company ~~and~~primarily ~~diarrhea~~focused ~~from~~on ~~acute~~the ~~gastroenteritis~~development ~~among people~~ of ~~all~~oral ~~ages~~recombinant invaccines ~~the~~based ~~United~~on ~~States.~~our ~~Each~~Vector-Adjuvant-Antigen ~~year,~~Standardized onTechnology ~~average,~~(“VAAST”) ~~norovirus~~proprietary ~~causes~~oral 19vaccine toplatform. ~~21 million~~We ~~cases of~~are ~~acute~~developing ~~gastroenteritis~~prophylactic ~~and~~vaccine ~~contributes~~candidates tothat ~~56,000~~target toa ~~71,000~~range ~~hospitalizations~~of ~~and~~infectious ~~570~~diseases, toincluding ~~800~~norovirus ~~deaths,~~(a ~~mostly~~widespread ~~among~~cause ~~young~~of ~~children~~acute ~~and~~gastroenteritis), ~~older~~coronavirus ~~adults.~~including ~~Typical~~SARS-CoV-2 ~~symptoms~~(the ~~include~~virus ~~dehydration,~~that ~~vomiting, diarrhea~~causes ~~with~~coronavirus ~~abdominal~~disease ~~cramps~~2019 (“COVID-19”)), and ~~nausea~~influenza. In aaddition, ~~study~~we ~~conducted~~have bygenerated ~~Pittsburg~~preclinical ~~School~~data offor ~~Medicine~~our infirst ~~2012,~~therapeutic ~~the~~vaccine ~~total~~candidate ~~economic~~targeting ~~burden~~cervical ofcancer ~~norovirus~~and indysplasia ~~the~~caused ~~United~~by ~~States~~human ~~was~~papillomavirus ~~estimated at $5~~(“HPV”).~~5 billion.~~ InOur aoral ~~more~~vaccines ~~recent~~are ~~study~~designed byto ~~CDC~~generate broad and ~~Johns~~durable ~~Hopkins~~immune ~~University,~~responses ~~the~~that ~~global~~may ~~economic~~protect ~~impact~~against ofa ~~norovirus~~wide ~~disease~~range ~~was estimated at $60 billion, $34 billion~~ of ~~which occurred~~infectious indiseases ~~high income countries including the United States, Europe~~ and ~~Japan.~~may ~~Virtually~~be ~~all~~useful ~~norovirus~~for ~~disease~~the istreatment ~~caused~~of bychronic ~~norovirus~~viral GIinfections and ~~GII~~cancer. ~~genotypes,~~Our ~~and~~investigational wevaccines are ~~developing~~administered using a ~~bivalent~~room ~~vaccine designed~~temperature-stable totablet, ~~protect~~rather ~~against~~than ~~both~~by injection.

~~Clinical~~Corporate ~~Trial~~History ~~Update. We have completed two Phase 1 clinical trials with our monovalent oral tablet vaccine for the GI.1 norovirus strain. The vaccine was well-tolerated~~ and generated broad systemic and mucosal immune responses. In the clinical Phase 1b dose optimization study in healthy adults in which we evaluated four different dosing regimens, all vaccine recipients (100%) in the high dose group responded as measured by a significant increase in norovirus-specific B cells of both IgA and IgG subtypes. In the same group, there was at least a two-fold increase of norovirus-specific antibody titers in serum in more than 90% of recipients. Reorganization

~~The bivalent~~Vaxart ~~norovirus~~Biosciences, ~~Phase 1~~Inc. ~~study,~~was ~~designed~~originally toincorporated ~~assess~~in ~~safety~~California ~~and~~under ~~immunogenicity~~the ofname ~~our~~West ~~norovirus~~Coast GIBiologicals, Inc.1 in March 2004 and ~~GII.4~~changed ~~vaccines~~its ~~administered~~name ~~concurrently~~to Vaxart, isInc. ~~nearing~~(“Private ~~completion~~Vaxart”) ~~and~~in weJuly ~~expect~~2007, ~~to announce~~when ~~topline~~it ~~results~~reincorporated in the ~~coming~~state ~~weeks.~~of Delaware.

On February 13, 2018, Private Vaxart completed a reverse merger (the “Merger”) with Aviragen Therapeutics, Inc. (“Aviragen”), pursuant to which Private Vaxart survived as a wholly owned subsidiary of Aviragen. Under the terms of the Merger, Aviragen changed its name to Vaxart, Inc. and Private Vaxart changed its name to Vaxart Biosciences, Inc. Our common stock subsequently began trading on The Nasdaq Capital Market under the symbol “VXRT.” In November 2025, our common stock was delisted from Nasdaq. In July 2025, our common stock began being listed on the on the OTCQX® Best Market under the trading symbol “VXRT.”

Our corporate headquarters and laboratory are located at 310 Utah Avenue, Suite 150, South San Francisco, California 94080, and our telephone number is (650) 550-3500. We maintain a website at https://www.vaxart.com, to which we regularly post copies of our press releases as well as additional information about us. The information contained on, or that can be accessed through, our website is not a part of this prospectus or the accompanying prospectus supplement. We have included our website address in this prospectus solely as an inactive textual reference.

Implications of Being a Smaller Reporting Company

We are a smaller reporting company as defined in Item 10(f)(1) of Regulation S-K, and we will remain a smaller reporting company until the fiscal year following:

● The determination that the value of our voting and non-voting common stock held by non-affiliates is more than $250 million measured on the last business day of our second fiscal quarter; or

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● ~~Following a~~Our ~~review~~annual ofrevenue ~~the development strategy for norovirus, Vaxart has deprioritized the monovalent GI.1 challenge study. Instead, the Company~~ is ~~preparing~~more tothan ~~initiate~~$100 amillion ~~Phase 2~~during safety and immunogenicity study with Vaxart's bivalent norovirus vaccine in 2020, to be followed by a Phase 3 efficacy study, assuming FDA concurrence. • Seasonal Influenza Vaccine. Influenza is a major cause of morbidity and mortality in the U.S. and worldwide and, according to the CDC, only 42% of eligible U.S. citizens were vaccinated in 2017/2018, with particularly low vaccination rates among adults between ages 18 and 49. We believe our oral tablet vaccine has the potential to improve the protective efficacy of currently available influenza vaccines and increase flu vaccination rates. Influenza is one of the most ~~common~~recently ~~global~~completed ~~infectious~~fiscal diseases, causing mild to life-threatening illness and even death. An estimated 350 million cases of seasonal influenza occur annually worldwide, of which three to five million cases are considered severe, causing 290,000 to 650,000 deaths per year ~~globally. During the flu season of 2017 - 2018, there were 79,400 flu-related deaths in the U.S. alone, according to the CDC. Very young children~~ and the elderly are at the greatest risk. In the United States, between 5% and 20% of the population contracts influenza, 226,000 people are hospitalized with complications of influenza, and between 3,000 and 49,000 people die from influenza and its complications each year, with up to 90% of the influenza-related deaths occurring in adults older than 65. The total economic burden of seasonal influenza has been estimated to be $87.1 billion, including medical costs which average $10.4 billion annually, while lost earnings due to illness and loss of life amount to $16.3 billion annually. We believe our ~~tablet~~voting ~~vaccine candidate has the potential to address many of the limitations of current injectable egg-based influenza vaccines, because: our tablet vaccine candidates are designed to create broad~~ and ~~durable immune responses, which may provide more effective immunity and protect against additional strain variants; our vaccine is delivered as a room temperature~~non-~~stable~~voting ~~tablet,~~common ~~which should~~stock ~~provide~~held ~~a more convenient method of administration to enhance patient acceptance, and should simplify distribution and administration; and,~~ by ~~using recombinant methods, we believe our tablet vaccine may be manufactured more rapidly than vaccines manufactured using egg~~non-~~based~~affiliates ~~methods,~~is ~~and~~valued ~~should~~over ~~eliminate the risk of allergic reactions to egg protein. Clinical Trial Update. In September 2018, we completed a~~ $~~15.7~~ 700 million ~~contract~~measured ~~with~~on the ~~U.S. Government~~ ~~through~~last ~~the~~business ~~Department~~day of ~~Health and Human Services, Office of Biomedical Advanced Research and Development Authority, or HHS BARDA, under which a Phase 2 challenge study of~~ our ~~H1N1~~second ~~flu~~fiscal ~~vaccine candidate was conducted~~quarter. Previously, we had announced that, in healthy volunteers immunized and then experimentally infected with H1 influenza, our H1 influenza oral tablet vaccine reduced clinical disease by 39% relative to placebo, a result that was superior to that of Fluzone, the market-leading injectable quadrivalent influenza vaccine, which reduced clinical disease by only 27%. Our tablet vaccine also showed a favorable safety profile, indistinguishable from placebo. On October 4, 2018, we presented data from the study demonstrating that our vaccine elicited a significant expansion of mucosal homing receptor plasmablasts to approximately 60% of all activated B cells, while Fluzone only maintained baseline levels of 20%. We believe plasmablasts are a key indicator of a protective mucosal immune response and a unique feature of our vaccines. This data also provided evidence that our vaccines protect through mucosal immunity, the first line of defense against mucosal infections such as flu, norovirus, RSV and others, a potential key advantage over injectable vaccines for these indications. At this time, we aim to finance development and commercialization of our seasonal quadrivalent influenza oral tablet vaccine through third-party collaboration and licensing arrangements, and/or

Smaller reporting companies are able to provide simplified executive compensation disclosures and have certain other reduced disclosure obligations, including, among other things, being required to provide only two years of audited financial statements and not being required to provide selected financial data, supplemental financial information or risk factors.

Further, as a smaller reporting company, we will not be required to provide an auditor attestation of management’s assessment of internal control over financial reporting, which is generally required for SEC reporting companies under Sarbanes-Oxley Act Section 404(b), and, in contrast to other reporting companies, we’ll have more time to file our annual and periodic reports.

THE OFFERING

The Offering


Issuer		Vaxart, Inc.

Shares of Common Stock Offered by the Selling Stockholder		Up to 32,914,599 shares of our common stock, comprised of (i) up to 32,467,532 shares of common stock that we may elect to issue and sell to Lincoln Park as Purchase Shares, in our sole discretion from time to time after the date of this prospectus, pursuant to the Purchase Agreement; and (ii) 447,067 Commitment Shares we issued to Lincoln Park on April 16, 2026 as consideration for its irrevocable commitment to purchase our common stock under the Purchase Agreement, for which we will not receive any cash consideration.

Number of Shares of Common Stock Outstanding Prior to this Offering⁽¹⁾		241,973,011 shares, which include the Commitment Shares.

Number of Shares of Common Stock to be Outstanding After this Offering⁽¹⁾		274,440,543 shares, which include the Commitment Shares.


Terms of Offering		The selling stockholder will determine when and how it sells the Purchase Shares offered in this prospectus, as described in the “Plan of Distribution.”

Use of Proceeds		We will receive no proceeds from the sale of shares of our common stock by Lincoln Park pursuant to this prospectus. We may receive up to $25 million aggregate gross proceeds under the Purchase Agreement from any sales of shares of our common stock we make to Lincoln Park pursuant to the Purchase Agreement after the date of this prospectus, assuming that we sell the full amount of our common stock available to us that we have the right, but not the obligation to sell to Lincoln Park under the Purchase Agreement. Any proceeds that we receive from sales of shares of our common stock to Lincoln Park under the Purchase Agreement will be used for working capital and general corporate purposes, including investing further in research and development efforts. See “Use of Proceeds” for a more complete description.

Risk Factors		Investing in our securities is highly speculative and involves a high degree of risk. See “Risk Factors” beginning on page 4 of this prospectus, and the other information included in this prospectus for a discussion of factors you should consider carefully before deciding to invest in our securities.

OTC Symbol for our Common Stock		“VXRT”

(1)	Assumes the purchase of all Purchase Shares by Lincoln Park. The number of shares of our common stock to be outstanding after this offering is based on 241,973,011 shares of common stock outstanding as of May 1, 2026, and excludes:

•

26,700,507 shares issuable upon the exercise of outstanding stock options at May 1, 2026, with a weighted-average exercise price of $1.52 per share;

•

6,770,405 shares issuable upon the vesting of outstanding restricted stock units (“RSUs”) at May 1, 2026;

•

6,920,277 shares reserved for future issuance under our 2019 Equity Incentive Plan as of May 1, 2026;

•

76,250 shares reserved for future issuance under our 2024 Inducement Award Plan as of May 1, 2026;

•

10,914 shares issuable upon the exercise of outstanding warrants at May 1, 2026, with a weighted-average exercise price of $22.99 per share; and

•

1,823,454 shares reserved for future issuance under our 2022 Employee Stock Purchase Plan (“ESPP”) at May 1, 2026.

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~~non-dilutive funding.~~RISK ~~In the future, we may also consider equity offerings and/or debt financings to fund the program.~~ FACTORS

~~In addition~~Investing toin our ~~conventional~~securities ~~seasonal~~involves ~~flu~~a ~~vaccine,~~high wedegree ~~entered~~of ~~into~~risk. aYou ~~research~~should ~~collaboration~~carefully ~~agreement~~consider ~~with~~and ~~Janssen~~evaluate ~~Vaccines &~~all ~~Prevention B~~of the information contained in this prospectus before you decide to purchase our securities.~~V.,~~ orIn ~~Janssen~~particular, toyou should carefully consider and evaluate the risks and uncertainties described under the heading “Risk Factors” in our ~~proprietary oral~~Annual ~~vaccine~~Report ~~platform~~on Form 10-K for the ~~Janssen~~year ~~universal~~ended ~~influenza~~December ~~vaccine~~31, ~~program.~~2025 ~~Under~~and Quarterly Report on Form 10-Q for the ~~agreement,~~quarter weended ~~will~~March ~~produce~~31, an2026. ~~oral~~Any ~~vaccine~~of ~~containing~~the ~~certain~~risks ~~proprietary~~and ~~antigens~~uncertainties ~~from~~set ~~Janssen~~forth below and ~~test~~in the ~~product~~ inAnnual aReport, ~~preclinical~~as ~~challenge~~updated ~~model.~~by ~~Upon~~annual, ~~completion~~quarterly ofand other reports and documents that we file with the ~~study~~SEC, ~~Janssen~~or ~~will~~any ~~have~~prospectus, ancould ~~option~~materially toand ~~negotiate~~adversely anaffect ~~exclusive~~our ~~worldwide~~business, ~~license~~results toof ~~our~~operations ~~technology~~and ~~encompassing~~financial condition, which in turn could materially and adversely affect the ~~Janssen~~value ~~antigens~~of any securities offered by this prospectus. As a result, you could lose all or part of your investment.

~~Cervical cancer~~Summary isof ~~the~~Risk ~~fourth most common cancer in women worldwide and in the United States with about 13,000 new cases diagnosed annually in the United States according to the National Cervical Cancer Coalition.~~ Factors

~~We have~~Our ~~tested~~business ~~our~~is ~~HPV-16~~subject ~~vaccine~~to ~~candidate~~numerous inrisks ~~two~~and ~~different~~uncertainties, ~~HPV-16~~discussed ~~solid~~in ~~tumor~~more ~~models~~detail in ~~mice. The vaccine elicited T cell responses and promoted migration of~~ the ~~activated~~following Tsection. ~~cells~~These ~~into~~risks ~~the tumors~~include, ~~leading~~ toamong ~~tumor~~others, ~~cell~~the ~~killing.~~following ~~Mice~~key ~~that received our HPV-16 vaccine showed a significant reduction in volume of their established tumors.~~ risks:

~~In October~~Risks ~~2018,~~related we filed a pre-IND meeting request for our HPV therapeutic vaccines, VXA-HPV16.1 and VXA-HPV18.1, with the FDA, and we subsequently submitted a pre-IND briefing package. We received feedback from the FDA in January 2019 providing guidance for the IND we plan to ~~submit. Based on~~ this ~~feedback, we expect to be able to file an IND for this product candidate in the course of 2020.~~ Offering

~~Based on~~● The ~~the~~sale ~~positive results~~ of our ~~cotton~~common ~~rat~~stock ~~study,~~to weLincoln ~~believe~~Park ~~our~~may ~~proprietary~~cause ~~oral~~dilution ~~vaccine~~and ~~platform is~~ the ~~optimal~~price ~~vaccine~~of ~~delivery~~our ~~system~~common ~~for~~stock ~~RSV, offering significant advantages over injectable vaccines. We aim~~ to develop a tablet RSV vaccine by licensing one or more RSV protein antigens that have demonstrated protection against RSV infection in clinical studies, or by partnering with a third party with RSV antigens that can be delivered with our platformfall.

~~Additional~~● It ~~Objectives~~ is not possible to predict the actual number of shares of common stock we will sell to Lincoln Park, the purchase price for those shares, or the actual gross proceeds we will receive.

● Investors who buy shares at different times will likely pay different prices and experience different levels of dilution.

● Our management will have broad discretion over the use of the net proceeds, if any, from sales of shares of our common stock to Lincoln Park.

Risks Related to Our Business, Financial Position and Capital Requirements

●	Throughout our operating history, we have generated limited product revenue.

●	We have incurred significant losses since our inception and expect to continue to incur significant losses for the foreseeable future and may never achieve or maintain profitability.

●	We are largely dependent on the success of our tablet vaccine candidates for the prevention of norovirus and coronavirus infection.

●	We have not yet produced a commercially viable vaccine and we may be never able to.

●	We will require additional capital to fund our operations.

●	We will need to expand our organization and may experience difficulties in managing growth.

●	Our business may be adversely affected by a pandemic, epidemic, or outbreak of an infectious disease, such as the ongoing coronavirus pandemic and the emergence of additional variants.

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~~Anti-Virals~~ Risks Related to Clinical Development, Regulatory Approval and Commercialization

~~Corporate~~● ~~Background~~ The regulatory pathway for coronavirus vaccines is evolving, as is the random appearance of novel variants, which may result in unexpected or unforeseen challenges.

~~Vaxart~~● ~~Biosciences, Inc.~~Clinical ~~was~~trials ~~originally~~are ~~incorporated~~very inexpensive, ~~California in March 2004 under the name West Coast Biologicals~~time-consuming, ~~Inc.~~ ~~The Company~~difficult ~~changed its name~~ to ~~Vaxart, Inc.~~design inand ~~July~~implement ~~2007,~~ and ~~reincorporated~~involve inan ~~the~~uncertain ~~state of Delaware~~outcome.

~~On February 13,~~● ~~2018,~~We weface ~~completed~~significant acompetition ~~business~~from ~~combination~~other ~~with~~biotechnology ~~Aviragen Therapeutics, Inc., or Aviragen, a publicly-traded company. Under the terms of the agreement~~ and ~~plan~~ ofpharmaceutical ~~merger and reorganization dated October 27, 2017, Vaxart, Inc~~companies. survived as a wholly owned subsidiary of Aviragen and changed its name to Vaxart Biosciences, Inc. and Aviragen changed its name to Vaxart, Inc. Our common stock subsequently began trading on the Nasdaq Capital Market under the symbol "VXRT."

●	Our tablet vaccine candidates may cause adverse effects resulting in failure to obtain approval from the U.S. Food and Drug Administration (the “FDA”) and/or product liability lawsuits against us.

●	We may be unable to manufacture sufficient bulk vaccine for our ongoing needs.

●	We are dependent on third parties for manufacturing and clinical trials.

●	We face numerous risks associated with our intellectual property.

Risks Related to Dependence on Third Parties

●	Our dependence on third parties could delay or prevent the development, approval, manufacturing, or any eventual commercialization of our product candidates.

●

We rely on third-party contract manufacturers for certain portions of our manufacturing process. If third-party contract manufacturers do not perform, fail to manufacture according to our specifications, or fail to comply with strict government regulations, our preclinical studies or clinical trials could be adversely affected and the development of our product candidates could be delayed or terminated, or we could incur significant additional expenses.

Risks Related to Intellectual Property

●	If we are unable to obtain and maintain patent protection for our oral vaccine platform technology and product candidates or if the scope of the patent protection obtained is not sufficiently broad, we may not be able to compete effectively in our markets.

●	We may be involved in lawsuits to protect or enforce our patents, the patents of our licensors or our other intellectual property rights, which could be expensive, time consuming and unsuccessful.

●	If a third party claims we are infringing on its intellectual property rights, we could incur significant expenses or be prevented from further developing or commercializing our product candidates, which could materially harm our business.

●	Obtaining and maintaining our patent protection depends on compliance with various procedures, document submission, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements.

●	We may not be able to protect our intellectual property rights throughout the world, which could impair our business.

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● Our ~~THE~~reliance ~~OFFERING~~ on third parties requires us to share our trade secrets, which increases the possibility that a competitor will discover them or that our trade secrets will be misappropriated or disclosed.

Common stock offered		shares
Pre-funded warrants offered		We are also offering to certain purchasers whose purchase of shares of common stock in this offering would otherwise result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding common stock immediately following the closing of this offering, the opportunity to purchase, if such purchasers so choose, pre-funded warrants to purchase shares of common stock, in lieu of shares of common stock that would otherwise result in any such purchaser's beneficial ownership exceeding 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding common stock. Each pre-funded warrant will be exercisable for one share of our common stock. The purchase price of each pre-funded warrant and accompanying common warrant (as described below) will be equal to the price at which a share of common stock and accompanying common warrant is being sold to the public in this offering, minus $0.10, and the exercise price of each pre-funded warrant will be $0.10 per share. The pre-funded warrants will be exercisable immediately and may be exercised at any time until all of the pre-funded warrants are exercised in full. This offering also relates to the shares of common stock issuable upon exercise of any pre-funded warrants sold in this offering. For each pre-funded warrant we sell, the number of shares of common stock we are offering will be decreased on a one-for-one basis. Because we will issue a common warrant for each share of our common stock and for each pre-funded warrant to purchase one share of our common stock sold in this offering, the number of common warrants sold in this offering will not change as a result of a change in the mix of the shares of our common stock and pre-funded warrants sold.
Common warrants offered by us in this offering		Common warrants to purchase an aggregate of shares of our common stock. Each share of our common stock and each pre-funded warrant will be sold together with a common warrant to purchase one share of our common stock. Each common warrant will have an exercise price of $ per share, will be immediately exercisable and will expire on the fifth anniversary of the original issuance date. This prospectus also relates to the offering of the shares of common stock issuable upon exercise of the common warrants.

Risks Related to our Common Stock

●	Our common stock is currently traded on the OTCQX, which may have an unfavorable impact on our stock price, liquidity, and the ability of investors to purchase or sell our shares.

●	Since our common stock is currently quoted on the OTCQX our stockholders may face significant restrictions on the resale of our common stock due to state “blue sky” laws and the sale of common stock in this offering is subject to state “blue sky” laws.

Risks Related to this Offering

The sale of our common stock to Lincoln Park may cause dilution and the subsequent sale of the shares of common stock acquired by Lincoln Park, or the perception that such sales may occur, could cause the price of our common stock to fall.

On April 16, 2026, we entered into the Purchase Agreement with Lincoln Park, pursuant to which Lincoln Park committed to purchase up to $25 million of our common stock. Other than the Commitment Shares, the shares of our common stock that may be issued under the Purchase Agreement may be sold by us to Lincoln Park from time to time at our discretion over a 24-month period from the Commencement Date through April 16, 2028, unless the Purchase Agreement is terminated prior to such date. The purchase price for the shares that we may sell to Lincoln Park under the Purchase Agreement will vary based on the price of our common stock at the time we initiate the sale. Depending on market liquidity at the time, sales of such shares may cause the trading price of our common stock to fall.

We generally have the right to control the timing and amount of any future sales of our shares to Lincoln Park. Sales of shares of our common stock to Lincoln Park under the Purchase Agreement, if any, will depend upon market conditions and other factors to be determined by us. We may ultimately decide to sell to Lincoln Park all, some or none of the shares of our common stock that may be available for us to sell pursuant to the Purchase Agreement. If and when we do sell shares to Lincoln Park, after Lincoln Park has acquired the shares, Lincoln Park may resell all, some or none of those shares at any time or from time to time in its discretion. Therefore, sales to Lincoln Park by us could result in substantial dilution to the interests of other holders of our common stock. Additionally, the sale of a substantial number of shares of our common stock to Lincoln Park, or the anticipation of such sales, could make it more difficult for us to sell equity or equity-related securities in the future at a time and at a price that we might otherwise desire, potentially limiting our access to capital markets when we may need additional financing.

It is not possible to predict the actual number of shares of common stock we will sell to Lincoln Park, the purchase price for those shares, or the actual gross proceeds we will receive.

Because the purchase price per share to be paid by Lincoln Park for the shares of common stock that we may elect to sell to Lincoln Park under the Purchase Agreement, if any, will fluctuate based on the market prices of our common stock at the time we elect to sell shares to Lincoln Park pursuant to the Purchase Agreement, if any, it is not possible for us to predict, as of the date of this prospectus and prior to any such sales, the number of shares of common stock that we will sell to Lincoln Park under the Purchase Agreement, the purchase price per share that Lincoln Park will pay for shares purchased from us under the Purchase Agreement, or the aggregate gross proceeds that we will receive from those purchases by Lincoln Park under the Purchase Agreement. Depending on market prices and the volume limitations in the Purchase Agreement, we may need to register additional shares under the Securities Act for resale by Lincoln Park in order to receive the full $25 million commitment, which would result in additional dilution to existing stockholders beyond what is disclosed in this prospectus.

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Option to purchase additional shares and/or common warrants		The underwriters have a 30-day option to purchase up to an additional shares of common stock and/or common warrants to purchase up to an additional shares of common stock from us at the public offering price less underwriting discounts and commissions.
Common stock to be outstanding after this offering		shares (or shares of common stock if the underwriters exercise their option to purchase additional shares in full) in each case assuming no sale of any pre-funded warrants and assuming no exercise of any common warrants issued in this offering.
Use of proceeds		We estimate that our net proceeds from this offering will be approximately $ million (or approximately $ million if the underwriters exercise their option to purchase additional shares and common warrants in full), based on an assumed combined public offering price of $ per share of common stock and and accompanying common warrant (the last reported sale price of our common stock on the Nasdaq Capital Market on , 2019), after deducting underwriting discounts and commissions and estimated offering expenses payable by us.
		We currently intend to use the net proceeds from this offering to support the clinical and preclinical development of our product candidates, to conduct clinical trials, including studies with our bivalent norovirus vaccine, to support the manufacturing of our vaccines, to advance our therapeutic HPV vaccine candidate, and for general corporate and working capital purposes. See the section titled "Use of Proceeds."
Risk factors		See "Risk Factors" beginning on page 11 of this prospectus, as well as other information included in this prospectus, for a discussion of factors you should read and consider carefully before investing in our securities.
Nasdaq Capital Market symbol		"VXRT." We do not intend to list the pre-funded warrants or common warrants on any securities exchange or nationally recognized trading system.

Lincoln Park may sell the shares of our common stock described in this prospectus in a number of different ways and at varying prices. The number of shares of our common stock ultimately offered for sale by Lincoln Park is dependent upon the number of shares of common stock, if any, we ultimately sell to Lincoln Park under the Purchase Agreement.

~~The number~~Investors ofwho buy shares ofat ~~common~~different ~~stock~~times towill belikely ~~outstanding~~pay ~~after~~different ~~this~~prices ~~offering~~and isexperience ~~based~~different onlevels 15of dilution,~~785,735~~ and the sale of the shares of common stock ~~outstanding~~acquired asby Lincoln Park could cause the price of ~~June 30,~~our ~~2019,~~common ~~and excludes:~~stock to decline.

Pursuant to the Purchase Agreement, we have discretion, subject to market demand and the conditions in the Purchase Agreement, to vary the timing, prices, and numbers of shares sold to Lincoln Park. If and when we do elect to sell shares of our common stock to Lincoln Park pursuant to the Purchase Agreement, after Lincoln Park has acquired such shares, Lincoln Park may resell all, some or none of such shares at any time or from time to time in its discretion and at varying prices. As a result, investors who purchase shares from Lincoln Park in this offering at different times will likely pay different prices for those shares, and so may experience different levels of dilution and in some cases substantial dilution and different outcomes in their investment results. Investors may experience a decline in the value of the shares they purchase from Lincoln Park in this offering as a result of future sales made by us to Lincoln Park at prices lower than the prices such investors paid. The discount at which we sell shares to Lincoln Park means that Lincoln Park can sell shares at prices lower than the market price at the time of our sale to Lincoln Park while still realizing a profit, which could exert additional downward pressure on our stock price. Further, the sale of a substantial number of shares of our common stock by Lincoln Park, or anticipation of such sales, could cause the trading price of our common stock to decline or make it more difficult for us to sell equity or equity-related securities in the future at a time and at a price that we might otherwise desire.

Our management will have broad discretion over the use of the net proceeds, if any, from sales of shares of our common stock to Lincoln Park, you may not agree with how we use the proceeds and the proceeds may not be used effectively.

This prospectus relates to shares of our common stock that may be offered and sold from time to time by Lincoln Park. We will not receive any proceeds upon the sale of shares by Lincoln Park. However, we may receive gross proceeds of up to $25 million from the sale of shares being registered for resale under this prospectus under the Purchase Agreement to Lincoln Park. The anticipated use of net proceeds from the sale of our common stock to Lincoln Park under the Purchase Agreement represents our intentions based upon our current plans and business conditions. Because we have not designated the amount of net proceeds from the sale of shares under the Purchase Agreement to be used for any particular purpose, our management will have broad discretion as to the use of the net proceeds from our sale of shares of common stock to Lincoln Park. Accordingly, you will be relying on the judgment of our management with regard to the use of those net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. It is possible that, pending their use, we may invest those net proceeds in a way that does not yield a favorable, or any, return for us. Further, our management may use the net proceeds for corporate purposes that may not improve our financial condition or market value. The failure of our management to use such funds effectively could have a material adverse effect on our business, financial condition, operating results and cash flows.

Risks Related to our Common Stock

Our common stock is currently traded on the OTCQX, which may have an unfavorable impact on our stock price, liquidity, and the ability of investors to purchase or sell our shares.

Our common stock is currently quoted on the OTCQX following our delisting from The Nasdaq Capital Market in November 2025. The OTCQX is a significantly more limited market than national securities exchanges such as the New York Stock Exchange or The Nasdaq Stock Market. The OTCQX is an inter-dealer quotation system with lower financial and qualitative standards for listing, less regulatory oversight, and generally lower trading volumes and liquidity than national exchanges. As a result, trading in our common stock may be subject to wider bid-ask spreads, increased volatility, and potential manipulation, which may have little to do with our actual business operations or prospects. This volatility could depress the market price of our common stock for reasons unrelated to our operating performance. Additionally, the Financial Industry Regulatory Authority (“FINRA”) has adopted rules that require broker-dealers to have reasonable grounds for believing an investment is suitable for a customer before recommending that investment. Because speculative low-priced securities may not be suitable for many customers, broker-dealers may be less likely to recommend our common stock, which could further limit the ability of investors to buy and sell our shares, reduce liquidity, and adversely affect our stock price.

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~~Unless otherwise~~Since ~~stated,~~our ~~information~~common stock is currently quoted on the OTCQX our stockholders may face significant restrictions on the resale of our common stock due to state “blue sky” laws and the sale of common stock in this ~~prospectus~~offering ~~assumes:~~is subject to state “blue sky” laws.

Each state has its own securities laws, often called “blue sky” laws, which (i) limit sales of securities to a state’s residents unless the securities are registered in that state or qualify for an exemption from registration, and (ii) govern the reporting requirements for broker-dealers doing business directly or indirectly in the state. Before a security is sold in a state, there must be a registration in place to cover the transaction, or the transaction must be exempt from registration. The applicable broker must also be registered in that state. Since our common stock is currently quoted on the OTCQX, a determination regarding registration will be made by those broker-dealers, if any, who agree to serve as the market-makers for our common stock. There may be significant state blue sky law restrictions on the ability of investors to sell, and on purchasers to buy, our securities. You should therefore consider the resale market for our securities to be limited, as you may be unable to resell your common stock without the significant expense of state registration or qualification.

Risks Related to Our Business, Financial Position and Capital Requirements

Throughout our operating history, we have generated limited product revenue.

Even though we generate royalty revenue from Inavir, our commercialized influenza product, we are at an early stage in our clinical development process and have not yet successfully completed a large-scale, pivotal clinical trial, obtained marketing approval, manufactured our tablet vaccine candidates at commercial scale, or conducted sales and marketing activities that will be necessary to successfully commercialize our product candidates. Consequently, predictions about our future success or viability may not be as accurate as they could be if we had a history of successfully developing and commercializing product candidates.

Our ability to generate significant revenue and achieve and maintain profitability will depend upon our ability to successfully complete the development of our tablet vaccine candidates for the prevention of norovirus, coronavirus and influenza infection and the treatment of cervical cancer and dysplasia caused by human papillomavirus (“HPV”) and other infectious diseases, and to obtain the necessary regulatory approvals. As disclosed elsewhere in this document, the Company is evaluating the best way to progress certain programs.

Even if we receive regulatory approval for the sale of any of our product candidates, we do not know when we will begin to generate significant revenue, if at all. Our ability to generate significant revenue depends on a number of factors, including our ability to:

●	set an acceptable price for our product candidates and obtain coverage and adequate reimbursement from third-party payors;

●	receive royalties on our products and product candidates including in connection with sales of Inavir;

●	establish sales, marketing, manufacturing and distribution systems;

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● add ~~SUMMARY~~or ~~SELECTED~~continue ~~CONSOLIDATED~~to ~~FINANCIAL~~scale ~~DATA~~ our operational, financial and management information systems and personnel, including personnel to support our clinical, manufacturing and planned future clinical development and commercialization efforts;

~~You~~● ~~should~~develop, ~~read the summary selected consolidated financial data below~~ in ~~conjunction~~collaboration with ~~"Management's Discussion and Analysis of Financial Condition and Results of Operations" and the consolidated financial statements~~others, ~~related~~manufacturing ~~notes~~capabilities ~~and~~for ~~other~~bulk ~~financial~~materials ~~information incorporated by reference in this prospectus. The summary selected consolidated financial data in this section are not intended to replace the consolidated financial statements~~ and ~~are~~manufacture ~~qualified~~commercial inquantities ~~their~~of ~~entirety~~our byproduct ~~the~~candidates ~~consolidated~~at ~~financial~~acceptable ~~statements~~cost ~~and related notes incorporated by reference in this prospectus.~~ levels;

~~The following~~● ~~consolidated~~achieve ~~statements~~broad ofmarket ~~operations~~acceptance ~~and comprehensive loss data for the years ended December 31, 2017 and 2018 and the consolidated balance sheet data as~~ of ~~December 31,~~ ~~2017 and 2018 have been derived from~~ our ~~audited~~product ~~consolidated~~candidates ~~financial statements incorporated by reference~~ in ~~this prospectus. We derived~~ the ~~consolidated~~medical ~~statements~~community ~~of operations~~ and ~~comprehensive~~with ~~loss~~third-party ~~data~~payors ~~for the six months ended June 30, 2018~~ and 2019 and the consolidated balance sheet data as of June 30, 2019 from our unaudited interim condensed consolidated financial statements and related notes incorporated by reference into this prospectus. Our unaudited interim condensed consolidated financial statements were prepared on the same basis as our audited financial statements and, in our opinion, reflect all adjustments, consisting only of normal recurring adjustments that are necessary for the fair statement of our unaudited interim condensed consolidated financial statements. Our historical results are not necessarily indicative of the results to be expected for any other period in the future, and our interim results are not necessarily indicative of the results to be expected for the full year or any other period. consumers;

	Year Ended December 31,						Six Months Ended June 30,
	2017			2018			2018			2019
							(unaudited)
	(in thousands, except share and per share data)
Consolidated Statements of Operations and Comprehensive Loss Data:
Revenue from government contract	$	5,839		$	1,344		$	1,130		$	—
Royalty revenue		—			1,340			963			3,728
Non-cash royalty revenue related to the sale of future royalties		—			1,475			18			1,764

Total revenue		5,839			4,159			2,111			5,492
Operating expenses:
Research and development		12,355			17,275			8,420			7,536
General and administrative		3,499			6,681			3,781			3,401
Impairment of intangible assets		—			1,600			1,600			—
Costs of exit from leased premise		—			359			—			—

Total operating expenses		15,854			25,915			13,801			10,937

Operating loss		(10,015	)		(21,756	)		(11,690	)		(5,445	)
Total other income and (expenses)		433			3,858			5,162			(1,268	)

Loss before provision for income taxes		(9,582	)		(17,898	)		(6,528	)		(6,713	)
Provision for income taxes		—			109			29			263

Net loss		(9,582	)		(18,007	)		(6,557	)		(6,976	)
Series B and C preferred dividend		(2,878	)		(339	)		(339	)		—

Net loss attributable to common stockholders	$	(12,460	)	$	(18,346	)		(6,896	)		(6,976	)



Net loss per share—basic and diluted	$	(91.65	)	$	(2.90	)	$	(1.26	)	$	(0.64	)



Shares used to compute net loss per share—basic and diluted		135,953			6,316,065			5,477,265			10,969,473

●	attract and retain an experienced management and advisory team;

●	launch commercial sales of our product candidates, whether alone or in collaboration with others;

●	develop, in-license or acquire product candidates or commercial-stage products that we believe can be successfully developed and commercialized; and

●	maintain, expand and protect our intellectual property portfolio.

Because of the numerous risks and uncertainties associated with vaccine development and manufacturing, we are unable to predict the timing or amount of increased development expenses, or when we will be able to achieve or maintain profitability, if at all. Our expenses could increase beyond expectations if we are required by the FDA, or comparable non-U.S. regulatory authorities, to perform studies or clinical trials in addition to those we currently anticipate. Even if our product candidates are approved for commercial sale, we anticipate incurring significant costs associated with the commercial launch of and the related commercial-scale manufacturing requirements for our product candidates. If we cannot successfully execute on any of the factors listed above, our business may not succeed.

We have incurred significant losses since our inception and expect to continue to incur significant losses for the foreseeable future and may never achieve or maintain profitability.

We expect to continue to incur substantial and increasing losses as we continue to pursue our business strategy. Our product candidates have not been approved for marketing in the U.S. and may never receive such approval. As a result, we are uncertain when or if we will achieve profitability and, if so, whether we will be able to sustain it. Our ability to generate significant revenue and achieve profitability is dependent on our ability to complete development, obtain necessary regulatory approvals, and have our product candidates manufactured and successfully marketed. We cannot be sure that we will be profitable even if we successfully commercialize one of our product candidates. If we do successfully obtain regulatory approval to market our tablet vaccine candidates, our revenues will be dependent, in part, upon the size of the markets in the territories for which regulatory approval is received, the number of competitors in such markets, the price at which we can offer our product candidates and whether we own the commercial rights for that territory. If the indication approved by regulatory authorities is narrower than we expect, or the treatment population is narrowed by competition, physician choice or treatment guidelines, we may not generate significant revenue from sales of our product candidates, even if approved. Even if we do achieve profitability, we may not be able to sustain or increase profitability on a quarterly or annual basis. If we fail to become and remain profitable, the market price of our common stock and our ability to raise capital and continue operations will be adversely affected.

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	As of December 31,
							As of June 30, 2019
	2017			2018
							(unaudited)
	(in thousands)
Consolidated Balance Sheet Data:
Cash and cash equivalents	$	1,571		$	11,506		$	16,258
Total assets		4,523			35,227			37,250
Long-term debt, including current portion		40,250			21,352			19,292
Total liabilities		43,245			23,989			21,405
Accumulated deficit		(79,982	)		(97,989	)		(104,992	)
Total stockholders' (deficit) equity		(38,722	)		11,238			15,845

We expect overall research and development expenses to increase significantly for any of our tablet vaccines, including those for the prevention of norovirus, coronavirus and influenza, as well as those for the treatment of HPV-related dysplasia and cancer, although we intend to fund a significant portion of these costs through partnering and collaboration agreements. In addition, even if we obtain regulatory approval, significant sales and marketing expenses will be required to commercialize the tablet vaccine candidates. As a result, we expect to continue to incur significant and increasing operating losses and negative cash flows for the foreseeable future. These losses have had and will continue to have an adverse effect on our financial position and working capital. As of March 31, 2026, we had an accumulated deficit of $455.0 million.

Our recurring losses from operations and negative cash flows had previously raised substantial doubt regarding our ability to continue as a going concern. Although management has concluded that such conditions have been alleviated as described elsewhere in this prospectus, we will require substantial additional funding to finance our operations, and if we are unable to raise capital, we could be forced to delay, reduce the scope of or eliminate certain of our development programs, or explore other strategic options.

As of March 31, 2026, we had $61.0 million of cash, cash equivalents and investments. We believe these funds are sufficient to fund our operations into the second quarter of 2027. Our ability to continue as a going concern is dependent upon our ability to raise additional capital through outside sources. We plan to raise additional capital through the sale of convertible stock, additional equity, debt financings, government programs, or strategic alliances with third parties. Such financing and funding may not be available at all, or on terms that are favorable to us. Failure to raise additional capital could have a material adverse effect on our business, results of operations, financial condition and/or our ability to fund our scheduled obligations on a timely basis or at all. If we are unable to continue as a going concern, we may be forced to liquidate our assets and the values we receive for our assets in liquidation or dissolution could be significantly lower than the values reflected in our consolidated financial statements.

We are largely dependent on the success of our tablet vaccines for the prevention of norovirus and coronavirus infection, which are still in their clinical development stage, and if one or both of these tablet vaccines do not receive regulatory approval or are not successfully commercialized, our business may be harmed.

None of our product candidates are in late-stage clinical development or approved for commercial sale and we may never be able to develop marketable tablet vaccine candidates. We expect that a substantial portion of our efforts and expenditures over the next few years will be devoted to our tablet vaccine candidates for norovirus and coronavirus. We are committing financial resources to the development of a norovirus vaccine and a coronavirus vaccine, which may cause delays in or otherwise negatively impact our other development programs. In addition, our management and scientific teams have dedicated substantial efforts to our norovirus vaccine and coronavirus vaccine development. Accordingly, our business currently depends heavily on the successful development, regulatory approval and commercialization of our norovirus and coronavirus tablet vaccines. These tablet vaccines may not receive regulatory approval or be successfully commercialized even if regulatory approval is received. The research, testing, manufacturing, labeling, approval, sale, marketing and distribution of tablet vaccine candidates are and will remain subject to extensive regulation by the FDA and other regulatory authorities in the U.S. and other countries that each have differing regulations. We are not permitted to market our tablet vaccines in the U.S. until we receive approval of a Biologics License Application (“BLA”) from the FDA, or in any foreign countries until we receive the requisite approval from such countries. Clinical studies for our norovirus vaccine candidate and our COVID-19 vaccine candidate have not been completed. As a result, we have not submitted a BLA to the FDA or comparable applications to other regulatory authorities and do not expect to be in a position to do so for the foreseeable future. Obtaining approval of a BLA is an extensive, lengthy, expensive and inherently uncertain process, and the FDA may delay, limit or deny approval of our tablet vaccines for many reasons, including:

●	We may not be able to demonstrate that our tablet vaccine is safe and effective to the satisfaction of the FDA;

●	the FDA may not agree that the completed Phase 1 and Phase 2 clinical trials of the norovirus vaccine and the Phase 1 and Phase 2 clinical trials of the COVID-19 vaccine satisfy the FDA’s requirements and may require us to conduct additional testing;

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● the ~~RISK~~results ~~FACTORS~~ of our clinical trials may not meet the level of statistical or clinical significance required by the FDA for marketing approval;

An● ~~investment in our securities involves a high degree of risk. You should carefully consider~~ the ~~risks~~FDA ~~described~~may ~~below as~~disagree ~~well~~with as the ~~other~~number, ~~information in this prospectus and incorporated by reference in this prospectus before making a decision to invest in shares of our common stock or pre-funded warrants and accompanying common warrants~~design, ~~including the risks described under "Risk Factors" in our Quarterly Report on Form 10-Q for the quarter ended June 30~~size, ~~2019.~~ ~~Our~~conduct ~~business faces significant risks and the risks described below may not be the only risks we face. Additional risks not presently known to us~~ or ~~that~~implementation ~~we currently believe are immaterial may also significantly impair our business operations. If any~~ of ~~these~~one ~~risks occur, our business, results of operations~~ or ~~financial~~more ~~condition and prospects could be harmed. In that event, the market price~~ of our ~~common~~clinical ~~stock and the value of the pre-funded warrants could decline, and you could lose all or part of your investment.~~trials;

~~Risks~~● ~~Related~~the contract research organizations, or CROs, that we retain to ~~this~~conduct ~~Offering~~ clinical trials may take actions outside of our control that materially and adversely impact our clinical trials;

~~Management~~● ~~will~~the ~~have~~FDA ~~broad~~may ~~discretion~~not asfind to the ~~use~~data offrom ~~the~~our ~~net~~preclinical ~~proceeds~~studies ~~from~~and ~~this~~clinical ~~offering,~~trials sufficient to demonstrate that the clinical and weother ~~may~~benefits ~~not use~~of ~~these~~our ~~proceeds~~tablet ~~effectively.~~ vaccines outweigh the safety risks;

We● ~~have not designated any portion of~~ the ~~net~~FDA ~~proceeds~~may ~~from~~disagree ~~this~~with ~~offering~~our tointerpretation ~~be used for any particular purposes. Our management will have broad discretion in the application~~ of ~~the~~data ~~net proceeds~~ from ~~this offering and could spend the proceeds in ways that do not improve~~ our ~~results~~preclinical ofstudies ~~operations or enhance the value of our common stock. Accordingly, you will be relying on the judgment of our management with regard to the use of these net proceeds,~~ and ~~you~~clinical will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. Our failure to apply these funds effectively could have a material adverse effect on our business, delay the development of our products and cause the price of our common stock to decline. trials;

~~You~~● ~~will~~the ~~experience~~FDA ~~immediate~~may ~~and~~not ~~substantial~~accept ~~dilution~~data ifgenerated ~~you~~at ~~purchase~~our ~~securities~~clinical intrial ~~this offering.~~ sites;

~~The~~● ~~price~~if atour ~~which~~NDA aor ~~share~~BLA ~~of common stock~~ is ~~sold~~reviewed inby ~~this~~an ~~offering~~advisory ~~will~~committee, ~~exceed~~ the ~~net~~FDA ~~tangible~~may ~~book~~have ~~value~~difficulties ~~(deficit)~~scheduling ~~per~~an ~~share~~advisory ofcommittee ~~our~~meeting ~~common stock outstanding prior to this offering. Assuming that shares of our common stock are sold~~ in ~~this offering,~~a ~~based~~timely onmanner anor ~~assumed~~the ~~combined~~advisory ~~public~~committee ~~offering~~may ~~price~~recommend ofagainst ~~$ per share~~approval of ~~common~~our ~~stock~~application ~~and~~or ~~accompanying~~may ~~common~~recommend ~~warrant~~that (the ~~last~~FDA ~~reported sale price of our common stock on the Nasdaq Capital Market on~~ require, ~~2019),~~as ~~after~~a ~~deducting~~condition ~~underwriting~~of ~~discounts and commissions and estimated offering expenses payable by us~~approval, ~~you~~additional ~~will~~preclinical ~~experience~~studies ~~immediate~~or ~~dilution~~clinical ~~of $ per share~~trials, ~~representing~~limitations ~~the~~on ~~difference~~approved ~~between~~labeling ~~the~~or ~~price~~distribution ~~you pay~~ and ~~our as adjusted~~use net tangible book value (deficit) per share as of June 30, 2019, after giving effect to this offering. See the section titled "Dilution" below for a more detailed illustration of the dilution you would incur if you participate in this offering. restrictions;

~~Purchasers~~● inthe ~~this~~FDA ~~offering~~ may ~~experience~~require ~~additional~~development ~~dilution~~ of ~~their~~a ~~investment~~risk inevaluation ~~the~~and ~~future.~~ mitigation strategy as a condition of approval;

We● may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. If additional capital is raised through the ~~sale~~FDA ofmay ~~equity~~identify ordeficiencies ~~convertible debt securities, or perceptions that those sales could occur, the issuance of these securities could result~~ in ~~further dilution to investors purchasing~~ our ~~common~~manufacturing ~~stock~~processes or ~~pre-funded~~facilities; ~~warrants in this offering or result in downward pressure on the price of our common stock,~~ and our ability to raise capital in the future. In order to raise additional capital, such securities may be at prices that are not the same as the price per share in this offering. We cannot assure you that we will be able to sell shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders, including investors who purchase securities in this offering. The price per share at which

●	the FDA may change its approval policies or adopt new regulations.

Currently, a significant portion of the funding to further develop our COVID-19 vaccine candidate is expected to come from BARDA funds. If BARDA were to eliminate, reduce, delay, or object to funding available to us under the 2024 ATI-RRPV Contract, this could have a significant, negative impact on our revenues and cash flows, and we may be forced to suspend or terminate the continued development of the product candidate or obtain alternative sources of funding.

In June 2024, we entered into the 2024 ATI-RRPV Contract with ATI, the Rapid Response Partnership Vehicle’s Consortium Management Firm funded by HHS BARDA. The 2024 ATI-RRPV Contract, as modified and amended to date, provides for a funding ceiling of approximately $460.7 million. Funding has been released pursuant to authorized milestones delineated in a series of contract modifications. Pursuant to Modification No. 6 to the 2024 ATI-RRPV Contract, dated March 10, 2026 (the most recent contract modification), the total amount of funding available for payment under the 2024 ATI-RRPV Contract is approximately $316.0 million.

We anticipate that a significant portion of the funding to further develop our COVID-19 vaccine candidate will come from the remaining amounts to be received under the 2024 ATI-RRPV Contract. The 2024 ATI-RRPV Contract provides that the government has the right to determine whether to fund the continued performance of the study after the initial funding. In the second half of 2024, the Company initiated and completed enrollment of the 400-participant sentinel cohort of its Phase 2b study comparing the Company’s XBB COVID-19 vaccine candidate to an approved mRNA XBB comparator. In January 2025, the independent data safety monitoring board (DSMB) reviewed 30-day sentinel cohort data and recommended the study proceed without modifications. Twelve-month follow-up data from the sentinel cohort is expected in the first half of 2026. In February 2025, ATI issued a stop work order on the 2024 ATI-RRPV Contract. Subsequently, in April 2025, the Company received written notification from ATI lifting the stop work order, permitting the Company to resume incurring costs, participating in meetings, and communicating with the Government and ATI concerning the project award. In May 2025, HHS BARDA approved initiation of dosing in the 10,000-participant main cohort of the Phase 2b study, and the Company announced the first participant dosed later that month.

In August 2025, ATI issued a second stop work order directing the Company to halt further screening and enrollment for the COVID-19 Phase 2b trial under the 2024 ATI-RRPV Contract. As of the August notification date, the Company had enrolled approximately half of the targeted number of participants for the main cohort of the study. On October 8, 2025, ATI issued a Follow-Up Notice confirming BARDA’s intent to stop all ongoing enrollment under the contract while permitting continued follow-up and planned analyses of both the sentinel cohort and the enrolled main study population. Contract funding is currently under review and is likely to be reduced commensurate with the reduced enrollment of approximately 5,000 participants versus the original planned enrollment of 10,000 participants in the main cohort of the Phase 2b study.

Even as we continue to receive funds under the 2024 ATI-RRPV Contract, the terms of the grant may unfavorably change, or the amount of funding may further decrease. If there is any government decision to discontinue funding under the 2024 ATI-RRPV Contract, our revenues and cash flows would be significantly and negatively impacted and we may be forced to seek alternative sources of funding, which may not be available on non-dilutive terms, terms favorable to us, or at all.

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~~we sell~~There ~~additional~~can ~~shares~~be ofno ~~our~~assurance ~~common~~that ~~stock~~Dynavax orTechnologies ~~securities~~Corporation, ~~convertible~~a ~~into~~Sanofi ~~common~~company ~~stock~~(“Dynavax”) inwill ~~future~~continue ~~transactions~~to ~~may~~perform bethe ~~higher~~obligations under the 2025 License and Collaboration Agreement or ~~lower~~that ~~than~~Dynavax ~~the~~will ~~price~~not ~~per~~exercise ~~share~~its inright ~~this~~to ~~offering.~~terminate the agreement.

~~There~~On February 10, 2026, Sanofi, a French société anonyme (“Sanofi”) completed its acquisition of Dynavax. As a result of the consummation of the merger, Dynavax became an indirect wholly owned subsidiary of Sanofi. Sanofi’s vaccine portfolio includes multiple influenza vaccines (Fluzone High-Dose, Flublok, Fluzone) and a co-commercialized protein-based COVID-19 vaccine, Nuvaxovid. Sanofi is noalso ~~public~~developing ~~market~~a combination, single-shot COVID-19/flu vaccine for ~~the~~adults ~~pre~~50+ using Novavax technology, targeting a non-~~funded~~mRNA ~~warrants~~approach. orSanofi ~~common~~can ~~warrants~~be ~~being~~expected ~~offered~~to make their decision for further investments in our Dynavax partnered COVID-19 vaccine and potentially other Vaxart assets in the context of this ~~offering~~larger vaccine portfolio.

~~There~~Our isdevelopment noof ~~established~~a ~~public~~norovirus ~~trading~~vaccine ~~market~~candidate ~~for~~and ~~the~~a ~~pre-funded~~coronavirus ~~warrants~~vaccine orcandidate ~~common~~is ~~warrants~~at ~~being~~an ~~offered~~early ~~in this offering, and we do not expect a market to develop~~stage. InWe ~~addition,~~may webe dounable ~~not intend~~ to ~~apply~~produce toan ~~list~~effective ~~the~~vaccine ~~pre-funded~~that ~~warrants~~successfully orimmunizes ~~common~~humans ~~warrants~~against onnorovirus ~~any securities exchange~~ or ~~nationally recognized trading system, including the Nasdaq Capital Market. Without~~ an ~~active~~effective ~~market,~~vaccine ~~the~~that ~~liquidity~~successfully ofimmunizes ~~the~~humans ~~pre-funded~~against ~~warrants~~coronavirus ~~and~~in ~~common~~a ~~warrants~~timely ~~will~~manner, beif ~~limited.~~at all.

~~Holders~~We are in the business of ~~our~~developing ~~pre-funded~~oral ~~warrants~~vaccines ~~and~~that ~~common~~are ~~warrants~~administered ~~will~~by ~~have~~tablet norather ~~rights~~than asby injection. Our development of the norovirus vaccine and a ~~common~~coronavirus ~~stockholder~~vaccine ~~until~~is ~~they acquire~~at ~~our~~an ~~common~~early ~~stock~~stage, and we may be unable to produce an effective vaccine that successfully immunizes humans against norovirus or an effective vaccine that successfully immunizes humans against coronavirus in a timely manner, if at all.

~~Until~~We ~~you~~may ~~acquire~~fail ~~shares of our common stock upon exercise of your pre-funded warrants or common warrants, you will have no rights with respect~~ to ~~shares~~produce ofan ~~our~~effective ~~common~~vaccine ~~stock~~that ~~issuable~~successfully ~~upon~~immunizes ~~exercise~~against ofnorovirus ~~your pre-funded warrants~~ or ~~common~~coronavirus ~~warrants.~~in ~~Upon~~a ~~exercise~~timely ~~of your pre-funded warrants or common warrants~~manner, ~~you~~if ~~will~~at ~~be entitled to exercise the rights of a common stockholder only as to matters for which the record date occurs after the exercise date~~all.

~~The~~We ~~pre~~are pursuing clinical development of vaccine candidates, employing our proprietary oral vaccine platform. While we have begun the Phase 2b clinical trial of our coronavirus vaccine candidate, none of our product candidates has advanced into late-~~funded~~stage ~~warrants~~clinical ~~and~~trials ~~common~~for ~~warrants~~the indications that we are ~~speculative~~pursuing development for. As such, clinical studies of our vaccine candidates may not be completed in ~~nature~~a timely manner, and we may not be able to produce an effective vaccine that successfully immunizes against norovirus or coronavirus any time soon, if at all.

~~Neither~~Even ~~the~~if ~~pre-funded~~we ~~warrants~~complete ~~nor~~our ~~the~~clinical ~~common~~trials ~~warrants~~as ~~offered~~planned ~~hereby~~and ~~confer~~our ~~any~~vaccine ~~rights~~candidates ofsuccessfully ~~common~~demonstrate ~~stock~~safety ~~ownership~~and ~~on their holders~~efficacy, ~~such~~we ~~as voting~~cannot ~~rights~~predict or the ~~right~~probability toor ~~receive~~timing ~~dividends,~~of ~~but~~subsequently ~~rather~~obtaining ~~merely~~regulatory ~~represent~~approval. ~~the~~Regulatory ~~right~~agencies tomay ~~acquire~~not ~~shares~~complete oftheir ~~common~~review ~~stock~~processes atin a ~~fixed~~timely ~~price. Specifically~~manner, ~~commencing~~and onwe ~~the date of issuance, holders of the pre-funded warrants~~ may ~~acquire~~not ~~the~~be ~~common~~able ~~stock~~to ~~issuable~~obtain ~~upon~~timely ~~exercise~~regulatory ofapproval, ~~such~~if ~~warrants~~ at ~~an exercise price of $0~~all.10 ~~per~~Further ~~share~~delays ~~of common stock and holders of the common warrants~~ may ~~acquire~~result ~~the common~~if ~~stock~~an ~~issuable~~FDA ~~upon~~advisory ~~exercise~~committee ofor ~~such~~other ~~warrants~~regulatory atauthority anrecommends ~~exercise~~non-approval ~~price~~or ofrestrictions ~~$ per~~on ~~share~~approval. ~~Moreover,~~In ~~following this offering~~addition, ~~the~~we ~~market~~may ~~value~~experience ofdelays ~~the~~or ~~pre-funded~~rejections ~~warrants~~based ~~and~~upon ~~common warrants~~additional isgovernment ~~uncertain~~regulation ~~and~~from ~~there~~future ~~can~~legislation ~~be no assurance that the market value of the pre-funded warrants~~ or ~~the~~administrative ~~common~~action, ~~warrants will equal~~ or ~~exceed~~changes ~~their~~in ~~public~~regulatory ~~offering~~agency ~~price.~~policy ~~There~~during ~~can be no assurance that~~ the ~~market~~period ~~price~~ of ~~the~~product ~~common~~development, ~~stock~~clinical ~~will~~trials, ~~ever~~and ~~equal or exceed~~ the ~~exercise~~review ~~price~~process. ofDelays ~~the pre-funded warrants~~ or ~~common~~failure ~~warrants,~~to ~~and~~obtain ~~consequently,~~necessary ~~whether~~regulatory itapprovals ~~will~~in ~~ever~~time becould ~~profitable~~have ~~for~~a ~~holders of~~material ~~the~~adverse ~~pre-funded~~effect ~~warrants~~on toour ~~exercise~~business, ~~the~~results ~~pre-funded warrants or the holders~~ of ~~the~~operations ~~common~~and ~~warrants~~financial ~~to exercise the common warrants~~condition.

~~Our~~The ~~failure~~likelihood toand ~~meet~~timing ~~the~~of ~~continued~~our ~~listing~~success ~~requirements~~further ofdepends ~~the~~on ~~Nasdaq~~our ~~Capital~~partners’ ~~Market~~performance ~~could~~and ~~result~~our inability ~~a delisting~~to ofmaintain ~~our~~relationships ~~common~~with ~~stock~~them.

~~Our~~If ~~common~~we ~~stock~~are isunsuccessful ~~listed~~in onmaintaining ~~the~~our ~~Nasdaq~~relationships ~~Capital~~with ~~Market,~~critical ~~which~~third ~~imposes,~~parties ~~among~~such ~~other~~as ~~requirements~~CROs ~~a minimum bid requirement. Our common stock traded for less than $1.00 for 30 consecutive trading days,~~ and ~~we received notice of this from the Listing Qualifications Staff of The Nasdaq Stock Market LLC on May 22~~CMOs, ~~2019. Under~~our ~~Nasdaq~~ability ~~Listing~~to ~~Rule 5810(c)(3)(A),~~develop weour ~~were~~oral ~~granted~~norovirus avaccine ~~180~~candidate ~~calendar~~or ~~day~~our ~~grace~~oral ~~period,~~coronavirus orvaccine ~~until~~candidate ~~November 18,~~and ~~2019,~~consequently tocompete ~~regain~~in ~~compliance with~~ the ~~minimum~~marketplace ~~bid~~could ~~price requirement. The minimum bid price requirement will~~ be ~~met~~impaired, ifand our ~~common~~results ~~stock has a minimum closing bid price~~ of atoperations ~~least~~may $1suffer.00 ~~per~~Even ~~share~~if ~~for a minimum of 10 consecutive business days during the 180 calendar day grace period. If~~ we doare ~~not regain compliance with the Rule by November 18~~successful, ~~2019 but~~ we ~~meet~~cannot ~~the~~assure ~~Nasdaq~~you ~~Capital~~that ~~Market~~these ~~initial~~relationships ~~inclusion~~will ~~criteria~~result ~~set forth~~ in ~~Nasdaq~~successful ~~Listing~~development ~~Rule 5505, except~~and ~~for~~commercialization ~~the~~of ~~minimum~~our ~~$1.00~~oral ~~per~~norovirus ~~share~~vaccine ~~bid~~candidate. ~~price~~Our ~~requirement~~failure, weor ~~will~~the befailure ~~granted~~of ~~an additional~~such ~~180-calendar~~partners ~~day~~or ~~compliance~~potential ~~period.~~partners, Ifto wecomply ~~do not regain compliance~~ with ~~the~~applicable ~~Rule~~regulations bycould ~~November 18,~~result ~~2019~~in ~~and~~sanctions ~~are~~being ~~not~~imposed ~~eligible~~on ~~for~~us, anincluding ~~additional~~clinical ~~compliance~~holds, ~~period at that time~~delays, ~~the Nasdaq~~suspension ~~staff~~or ~~will~~withdrawal ~~provide~~of ~~written~~approval ~~notification~~ to usconduct ~~that~~clinical ~~our~~investigations, ~~common~~license ~~stock~~revocation, ~~will~~operating berestrictions ~~delisted.~~and Atcriminal ~~that time~~prosecutions, weany ~~may~~of ~~appeal~~which ~~the~~could ~~Nasdaq~~significantly ~~staff's~~and ~~delisting~~adversely ~~determination~~affect tosupplies aof ~~Nasdaq~~our ~~Listing~~potential ~~Qualifications Panel~~norovirus vaccine.

Manufacturing any drug product with recombinant technology such as our adenovirus type 5 based vaccines presents technical challenges. Our manufacturing partners may not be able to successfully manufacture any vaccine with our VAAST platform, or to comply with cGMP, regulations or similar regulatory requirements. The number of doses of our potential vaccine that we are able to produce is dependent on our ability to successfully and rapidly scale-up manufacturing capacity. The number of doses that we will be able to produce is also dependent in large part on the dose of the vaccine required to be administered to patients which will be determined in our clinical trials. To properly scale-up and develop a commercial process, we may need to expend significant resources, expertise, and capital.

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~~pursuant to~~Scale ~~the~~up ~~procedures~~can ~~set~~present ~~forth~~problems insuch ~~the~~as ~~applicable~~difficulties ~~Nasdaq~~with ~~Listing~~production ~~Rules.~~costs ~~There~~and ~~can~~yields, bequality nocontrol, including stability of the product candidate and quality assurance ~~that~~testing, weshortages ~~will~~of bequalified ~~able~~personnel toor ~~regain~~key raw materials, and compliance orwith ~~that~~strictly ~~Nasdaq~~enforced ~~will~~federal, ~~grant~~state, usand aforeign ~~further~~regulations. ~~extension~~Our ~~of time~~contract tomanufacturers ~~regain~~may ~~compliance,~~not ifperform ~~necessary~~as agreed. If any manufacturer encounters these or other difficulties, our ability to provide product candidates to patients in our clinical trials could be jeopardized.

~~The delisting~~We ofwill ~~our~~require ~~common~~additional ~~stock from Nasdaq may make it more difficult for us to raise~~ capital ~~on favorable terms in the future, or at all. Such a delisting would likely have a negative effect on the price of our common stock and would impair your ability~~ to ~~sell~~fund ~~or purchase~~ our ~~common stock when you wish to do so. Further~~operations, and if ~~our~~we ~~common~~fail ~~stock were~~ to beobtain ~~delisted~~necessary ~~from the Nasdaq Capital Market~~financing, ~~our~~we ~~common~~may ~~stock~~not ~~would cease to~~ be ~~recognized~~able ~~as a covered security and we would be subject~~ to ~~additional~~complete ~~regulation in each state in which we offer our securities. Moreover, there is no assurance that any actions that we take to restore our compliance with~~ the ~~Nasdaq~~development ~~minimum~~and ~~bid~~commercialization ~~requirement would stabilize the market price or improve the liquidity~~ of our ~~common~~tablet ~~stock, prevent~~vaccine ~~our common stock from falling below the Nasdaq minimum bid price required for continued listing again, or prevent future non-compliance with Nasdaq's listing requirements~~candidates.

~~There can~~We beexpect noto ~~assurance~~spend ~~that~~substantial weamounts ~~will continue~~ to ~~meet~~complete the ~~minimum~~development ~~bid~~of, ~~price~~seek ~~requirement,~~regulatory orapprovals ~~any~~for ~~other~~and ~~requirement~~commercialize inour ~~the~~tablet ~~future~~vaccine candidates. IfWe wewill ~~fail~~require substantial additional capital to ~~meet~~complete the ~~minimum~~development ~~bid~~and ~~price~~potential ~~requirement, or~~commercialization ~~other~~of ~~applicable~~our ~~Nasdaq~~tablet ~~listing~~vaccine ~~requirements~~candidates for norovirus, ~~including~~coronavirus, ~~maintaining~~influenza ~~minimum~~and ~~levels~~HPV and the development of ~~stockholders'~~other ~~equity~~product candidates. If we are unable to raise capital or ~~market~~find ~~values~~appropriate ofpartnering ~~our~~or ~~common~~licensing ~~stock~~collaborations, ~~our~~when ~~common~~needed ~~stock~~or ~~could~~on beacceptable ~~delisted.~~terms, Ifwe ~~our~~could ~~common stock~~be ~~were~~forced to ~~be delisted~~delay, ~~the~~reduce ~~liquidity~~or eliminate one or more of our ~~common~~development ~~stock~~programs ~~would~~or beany ~~adversely~~future ~~affected~~commercialization efforts. In addition, ~~and~~attempting to secure additional financing may divert the ~~market~~time ~~price~~and attention of our ~~common~~management ~~stock~~from ~~could~~day-to-day ~~decrease.~~activities and harm our development efforts.

~~Unless~~As of March 31, 2026, we had $61.0 million of cash, cash equivalents and short-term investments. We maintain our ~~common~~cash, ~~stock~~cash ~~continues~~equivalents toand beshort-term ~~listed~~investments onwith ahigh ~~national~~quality, ~~securities~~accredited ~~exchange~~financial itinstitutions. ~~will~~However, ~~become~~some ~~subject~~of these accounts exceed federally insured limits, and, while we believe the Company is not exposed to significant credit risk due to the ~~so-called~~financial ~~"penny~~strength ~~stock"~~of ~~rules~~these ~~that~~depository ~~impose~~institutions ~~restrictive~~or ~~sales~~investments, ~~practice~~the ~~requirements~~failure or collapse of one or more of these depository institutions or default on these investments could materially adversely affect our ability to recover these assets and/or materially harm our financial condition.

IfAlthough we ~~are~~believe ~~unable~~such tocash, ~~maintain~~cash ~~the~~equivalents ~~listing~~and ofshort-term ~~our~~investments ~~common~~are ~~stock~~sufficient onto ~~Nasdaq~~fund orour ~~another~~operations ~~national~~under ~~securities exchange,~~ our ~~common~~current ~~stock~~operating ~~could~~plan ~~become subject~~for toat ~~the~~least ~~so-called~~one ~~"penny~~year ~~stock"~~from ~~rules if~~ the ~~shares~~date ~~have~~of aissuance ~~market value~~ of ~~less~~this ~~than~~prospectus, ~~$5.00~~our ~~per~~estimate ~~share.~~as ~~The SEC has adopted regulations that define a penny stock~~ to ~~include~~what ~~any~~we ~~stock~~will ~~that~~be ~~has~~able ~~a market price of less than $5.00 per share, subject~~ to ~~certain~~accomplish ~~exceptions,~~is ~~including~~based ~~an exception for stock traded~~ on aassumptions ~~national~~that ~~securities~~may ~~exchange.~~prove ~~The SEC regulations impose restrictive sales practice requirements on broker-dealers who sell penny stocks~~ to ~~persons~~be ~~other than established customers and accredited investors. An accredited investor generally is a person whose individual annual income exceeded $200~~inaccurate,~~000,~~ ~~or whose joint annual income with a spouse exceeded $300,000 during the past two years~~ and ~~who~~we ~~expects~~could ~~their~~exhaust ~~annual~~our ~~income~~available tocapital ~~exceed~~resources ~~the~~sooner ~~applicable~~than ~~level~~is ~~during~~currently ~~the current year, or a person with net worth in excess of $1~~expected.~~0 million,~~ ~~not~~Because ~~including~~ the ~~value~~length of ~~the~~time ~~investor's principal residence~~ and ~~excluding~~activities ~~mortgage~~associated ~~debt~~with ~~secured~~successful bydevelopment ~~the~~of ~~investor's~~our ~~principal~~product ~~residence~~candidates upis tohighly ~~the estimated fair market value of the home~~uncertain, ~~except~~we ~~that~~are ~~any~~unable ~~mortgage debt incurred by the investor within 60 days prior~~ to ~~the~~estimate ~~date of~~ the ~~transaction~~actual ~~shall~~funds ~~not~~we bewill ~~excluded~~require ~~from~~for ~~the~~development ~~determination~~and ofany ~~the~~approved ~~investor's~~marketing ~~net~~and ~~worth unless~~commercialization ~~the mortgage debt was incurred to acquire the residence~~activities. ~~For~~Our ~~transactions~~future ~~covered~~funding ~~by this rule~~requirements, ~~the~~both ~~broker-dealer~~near ~~must make a special suitability determination for the purchaser~~ and ~~must~~long-term, ~~have received~~will ~~the~~depend ~~purchaser's written consent to the transaction prior to sale. This means that if we are unable maintain the listing of our common stock~~ on amany ~~national~~factors, ~~securities exchange~~including, ~~the~~but ~~ability~~not ~~of stockholders~~limited to ~~sell their common stock in the secondary market could be adversely affected.~~ :

~~If a~~● ~~transaction~~our ~~involving~~ability ~~a penny stock is not exempt from the SEC's rule, a broker-dealer must deliver a disclosure schedule relating~~ to ~~the~~enter ~~penny~~into ~~stock~~partnering ~~market to each investor prior to a transaction. The broker-dealer also must disclose the commissions payable to both the broker-dealer~~ and ~~its~~collaboration registered representative, current quotations for the penny stock, and, if the broker-dealer is the sole market-maker, the broker-dealer must disclose this fact and the broker-dealer's presumed control over the market. Finally, monthly statements must be sent disclosing recent price information for the penny stock held in the customer's account and information on the limited market in penny stocks. agreements;

●	the initiation, progress, timing, costs and results of our planned clinical trials;

●	the outcome, timing and cost of meeting regulatory requirements established by the FDA, the European Medicines Agency, or EMA, and other comparable foreign regulatory authorities;

●	the cost of filing, prosecuting, defending and enforcing our patent claims and other intellectual property rights;

●	the cost of defending potential intellectual property disputes, including any patent infringement actions brought by third parties against us now or in the future;

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● the ~~SPECIAL~~effect ~~NOTE~~of ~~REGARDING~~competing ~~FORWARD-LOOKING~~technological ~~STATEMENTS~~ and market developments;

~~This~~● ~~prospectus and~~ the ~~documents~~cost ~~we have filed with the Securities and Exchange Commission, or the SEC, that are incorporated by reference contain "forward-looking statements" within the meaning~~ of ~~Section 27A~~establishing ~~of the Securities Act of 1933~~sales, asmarketing ~~amended, or the Securities Act,~~ and ~~Section 21E~~distribution ofcapabilities ~~the~~in ~~Securities~~regions ~~Exchange~~where ~~Act~~we ~~of 1934,~~choose ~~or the Exchange Act. These statements relate~~ to ~~future~~commercialize ~~events or to~~ our ~~future~~product ~~operating~~candidates oron ~~financial performance and involve known and unknown risks, uncertainties and other factors which may cause~~ our ~~actual~~own; results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. Forward-looking statements may include, but are not limited to, statements about:and

~~In some~~● ~~cases,~~the ~~you can identify forward-looking statements by terms such as "anticipates~~initiation," ~~"believes~~progress," ~~"could,"~~timing ~~"estimates,"~~and ~~"intends,"~~results ~~"may,"~~of ~~"plans," "potential," "will," "would," or~~ the ~~negative~~commercialization of ~~these terms or other similar expressions. These statements reflect~~ our ~~current~~product ~~views with respect to future events and are based on assumptions and are subject to risks and uncertainties. Given these uncertainties~~candidates, ~~you~~if ~~should not place undue reliance on these forward-looking statements. We discuss in greater detail many of these risks in the section titled "Risk Factors"~~approved, ~~in any free writing prospectuses we may authorize~~ for ~~use~~commercial in connection with this offering, and in our most recent Quarterly Report on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entiretysale. Also, these forward-looking statements represent our estimates and assumptions only as of the date of the document containing the applicable statement. Unless required by law, we undertake no obligation to update or revise any forward-looking statements to reflect new information or future events or developments.

~~In addition,~~Additional ~~statements~~funding ~~that~~may ~~"we~~not ~~believe"~~be ~~and~~available ~~similar~~on ~~statements~~acceptable ~~reflect~~terms, ~~our~~or ~~beliefs~~at ~~and opinions on the relevant subject~~all. ~~These~~If ~~statements~~we are ~~based~~unable ~~upon~~to ~~information~~raise ~~available~~additional tocapital usin ~~as of~~sufficient ~~the~~amounts ~~date~~or ofon ~~this~~terms ~~prospectus,~~acceptable ~~and~~to ~~while~~us, we ~~believe~~may ~~such~~have ~~information~~to ~~forms a~~significantly ~~reasonable basis for such statements~~delay, ~~such~~scale ~~information~~back ~~may~~or bediscontinue ~~limited~~the development or ~~incomplete,~~commercialization ~~and~~of our ~~statements~~product ~~should~~candidates ~~not be~~or ~~read~~potentially todiscontinue ~~indicate that we~~ operations.

Raising additional funds by issuing securities may cause dilution to existing stockholders, and raising funds through lending and licensing arrangements may restrict our operations or require us to relinquish proprietary rights.

We expect that significant additional capital will be needed in the future to continue our planned operations. Until such time, if ever, as we can generate substantial product revenues, we expect to finance our cash needs through a combination of equity offerings, royalties, debt financings, government programs, strategic alliances and license and development agreements in connection with any collaborations. We do not currently have any committed external source of funds. To the extent that we raise additional capital by issuing equity securities, our existing stockholders’ ownership may experience substantial dilution, and the terms of these securities may include liquidation or other preferences that adversely affect our common stockholders’ rights. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures, declaring dividends, creating liens, redeeming our stock or making investments.

If we raise additional funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings when needed, or through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties on acceptable terms, we may be required to delay, limit, reduce or terminate our product development or future commercialization efforts or grant rights to develop and market product candidates that we would otherwise develop and market ourselves.

The price of our common stock has been volatile and fluctuates substantially, which could result in substantial losses for stockholders.

Our stock price has been, and in the future may be, subject to substantial volatility. As a result of this volatility, our stockholders could incur substantial losses. The stock market in general, and the market for biopharmaceutical companies in particular, has experienced extreme volatility that has often been unrelated to the operating performance of particular companies. As a result of this volatility, you may not be able to sell your common stock at or above your initial purchase price.

The market price for our common stock may be influenced by many factors, including the results of clinical trials of our products or those of our competitors, regulatory or legal developments, developments, disputes, or other matters concerning patent applications, issued patents, or other proprietary rights, our ability to recruit and retain key personnel, public announcements by us or our strategic collaborators regarding the progress of our development candidates similar public announcements by our competitors, and other factors set forth in this document and our other reports filed with the SEC.

If our quarterly or annual results fall below the expectations of investors or securities analysts, the price of our common stock could decline substantially. Furthermore, any quarterly or annual fluctuations in our results may, in turn, cause the price of our stock to fluctuate substantially. We believe that period-to-period comparisons of our results are not necessarily meaningful and should not be relied upon as an indication of our future performance.

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~~have conducted~~In anaddition, ~~exhaustive~~public ~~inquiry~~statements ~~into~~by us, government agencies, the media or ~~review~~others ofrelating to the SARS-CoV-2 outbreak (including regarding efforts to develop a COVID-19 vaccine) have in the past resulted, ~~all~~and ~~potentially~~may ~~available~~in ~~relevant~~the future result, in significant fluctuations in our stock price. Given the global focus on the coronavirus outbreak, any information in the public arena on this topic, whether or not accurate, could have an outsized impact (either positive or negative) on our stock price. ~~These~~Information ~~statements~~related ~~are~~to ~~inherently~~our ~~uncertain~~development, manufacturing and ~~investors~~distribution ~~are~~efforts ~~cautioned~~with ~~not~~respect to ~~unduly~~our ~~rely~~vaccine ~~upon these~~candidates, ~~statements.~~or information regarding such efforts by competitors with respect to their potential vaccines, may also impact our stock price.

~~You should~~Our ~~read~~stock ~~this~~price ~~prospectus,~~is ~~together~~likely ~~with~~to ~~the~~continue ~~documents~~to webe ~~have~~volatile ~~filed~~and ~~with~~subject ~~the~~to ~~SEC~~significant ~~that~~price ~~are~~and ~~incorporated~~volume byfluctuations ~~reference~~in ~~and~~response ~~any~~to ~~free~~market ~~writing~~and ~~prospectus~~other ~~that~~factors, weincluding: ~~may~~the ~~authorize~~other ~~for~~factors ~~use~~ discussed in ~~connection~~in ~~with~~future ~~this~~periodic ~~offering~~reports; ~~completely~~variations ~~and~~in ~~with~~our ~~the~~quarterly ~~understanding~~operating ~~that~~results from our ~~actual~~expectations ~~future~~or ~~results~~those ~~may~~of besecurities ~~materially~~analysts ~~different~~or ~~from~~investors; ~~what~~downward werevisions ~~expect.~~in Wesecurities ~~qualify~~analysts’ ~~all~~estimates; ofand ~~the~~announcement ~~forward-looking~~by ~~statements in~~us ~~the~~or ~~foregoing~~our ~~documents~~competitors byof ~~these~~significant ~~cautionary~~acquisitions, ~~statements.~~strategic partnerships, joint ventures or capital commitments.

Market prices for securities of early-stage pharmaceutical, biotechnology and other life sciences companies have historically been particularly volatile. Some of the factors that cause the market price of our common stock to fluctuate include:

●	our ability to develop product candidates and conduct clinical trials that demonstrate our product candidates are safe and effective;

●	our ability to negotiate and receive royalty payments on the sales of our product candidates including Inavir;

●	our ability to obtain regulatory approvals for our product candidates, and delays or failures to obtain such approvals;

●	failure of any of our product candidates to demonstrate safety and efficacy, receive regulatory approval and achieve commercial success;

●	failure to maintain our existing third-party license, manufacturing and supply agreements;

●	our failure, or that of our licensors, to prosecute, maintain, or enforce our intellectual property rights;

●	changes in laws or regulations applicable to our product candidates;

●	any inability to obtain adequate supply of product candidates or the inability to do so at acceptable prices;

●	adverse regulatory authority decisions;

●	introduction of new or competing products by our competitors;

●	failure to meet or exceed financial and development projections that we may provide to the public;

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● the ~~MARKET~~perception ~~AND~~of ~~INDUSTRY~~the ~~DATA~~ pharmaceutical industry by the public, legislatures, regulators and the investment community;

~~This~~● ~~prospectus~~announcements and the documents incorporated by reference in this prospectus contain market data and industry statistics and forecasts that are based on independent industry publications and other publicly available information. Although we believe that these sources are reliable, we do not guarantee the accuracy or completeness of ~~this information~~significant ~~and we have not independently verified this information. Although we are not aware of any misstatements regarding the market and industry data presented or incorporated by reference in this prospectus~~acquisitions, ~~these~~strategic ~~estimates involve risks and uncertainties and are subject to change based on various factors~~partnerships, ~~including~~joint ~~those discussed in the section titled "Risk Factors" and any related free writing prospectus. Accordingly~~ventures, ~~investors~~or ~~should~~capital ~~not~~commitments ~~place~~by ~~undue~~us ~~reliance~~or onour ~~this information.~~ competitors;

●	disputes or other developments relating to proprietary rights, including patents, litigation matters, and our ability to obtain intellectual property protection for our technologies;

●	additions or departures of key personnel;

●	significant lawsuits, including intellectual property or stockholder litigation;

●	if securities or industry analysts do not publish research or reports about us, or if they issue adverse or misleading opinions regarding our business and stock;

●	changes in the market valuations of similar companies;

●	general market or macroeconomic conditions;

●	sales of our common stock by our existing stockholders in the future;

●	trading volume of our common stock;

●	adverse publicity relating to our markets generally, including with respect to other products and potential products in such markets;

●	changes in the structure of health care payment systems; and

●	period-to-period fluctuations in our financial results.

Moreover, the stock markets in general have experienced substantial volatility that has often been unrelated to the operating performance of individual companies. These broad market fluctuations may also adversely affect the trading price of our common stock.

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Our common ~~USE~~stock OFhas ~~PROCEEDS~~ been delisted from The Nasdaq Capital Market. There can therefore be no assurance that it will trade on a national exchange again.

WeEffective ~~estimate~~July ~~that~~8, 2025, Nasdaq suspended trading in our ~~net~~common ~~proceeds~~stock ~~from~~and subsequently informed the ~~sale of shares~~Company ofon ~~common~~September ~~stock~~19, in2025, ~~this~~that ~~offering~~the Company’s common stock will be ~~approximately $ million,~~delisted ~~based~~from onThe anNasdaq ~~assumed~~Capital ~~combined~~Market ~~public~~due ~~offering~~to ~~price~~the ofCompany’s ~~$ per~~ongoing ~~share~~failure ofto ~~common~~comply ~~stock~~with ~~and accompanying~~the ~~common~~minimum ~~warrant~~bid price requirement under Nasdaq Listing Rule 5550(~~the~~a)(2). ~~last~~Vaxart, ~~reported~~Inc. ~~sale~~was ~~price~~formally ofdelisted ~~our common~~from ~~stock~~Nasdaq onfollowing a final determination by the Nasdaq's ~~Capital~~Listing ~~Market~~Qualifications Department on , ~~2019)~~November 3, ~~after~~2025. ~~deducting~~Our ~~underwriting~~common ~~discounts~~stock ~~and commissions~~is ~~and~~currently ~~estimated~~quoted ~~offering~~on ~~expenses~~the ~~payable~~OTCQX byunder ~~us.~~the Ifticker ~~the~~symbol ~~underwriters~~“VXRT.” ~~exercise their~~We ~~option~~can toprovide ~~purchase additional~~no ~~shares~~assurance ofthat our common stock ~~together~~will ~~with~~continue ~~accompanying~~to ~~common~~trade ~~warrants~~on ~~to purchase~~this upmarket, whether broker-dealers will continue to ~~shares~~ provide public quotes for our common stock, and whether the trading volume of our common stock will be sufficient to provide for an efficient trading market in ~~full,~~the wefuture. ~~estimate~~Stocks ~~that our~~trading ~~net~~in ~~proceeds~~the ~~from~~OTC ~~this~~Markets ~~offering~~generally ~~will~~have besubstantially ~~approximately~~less ~~$ million~~liquidity, ~~after~~hence, ~~deducting~~decreasing ~~underwriting~~our ~~discounts~~ability ~~and~~to ~~commissions~~issue ~~and~~additional ~~estimated~~securities ~~offering~~or ~~expenses~~obtain ~~payable~~additional ~~by us~~financing. ~~We cannot~~The ~~predict~~National ~~when~~Securities Markets Improvement Act of 1996, which is a federal statute, prevents or ifpreempts the ~~common~~states ~~warrants~~from ~~will~~regulating bethe ~~exercised~~sale of certain securities, which are referred to as “covered securities.” As Itwe isare ~~possible~~currently ~~that~~no ~~the~~longer ~~common~~listed ~~warrants~~on ~~may~~Nasdaq, ~~expire~~our securities do not qualify as covered securities under the statute, and ~~may~~we ~~never~~are besubject ~~exercised.~~to regulation in each state in which we offer our securities.

~~A $0.25~~Our ~~increase~~business ~~(decrease)~~may inbe ~~the~~adversely ~~assumed~~affected ~~combined~~by ~~public~~a ~~offering~~pandemic, ~~price~~epidemic, ofor ~~$ per~~outbreak ~~share~~ of ~~common~~an ~~stock~~infectious ~~and accompanying common warrant (the last reported sale price of our common stock on the Nasdaq Capital Market on~~ disease, ~~2019)~~such ~~would~~as ~~increase (decrease) the expected net cash proceeds of the offering to us by $ million~~COVID-19, ~~assuming that~~ the ~~number~~severe ofacute ~~shares~~respiratory ~~offered by us~~syndrome, ~~as set forth on~~ the ~~cover~~H5N1 ~~page~~strain of ~~this~~avian ~~prospectus remains the same~~influenza, ~~after deducting underwriting discounts and commissions and estimated offering expenses payable by us. An increase (decrease) of 1.0 million shares in~~ the ~~number~~H1N1 ofstrain ~~shares~~ of ~~common~~swine ~~stock offered by us would increase (decrease) the net proceeds to us from this offering by $ million~~flu, ~~assuming that the assumed combined public offering price of $ per share of common stock~~ and ~~accompanying~~ ~~common warrant remains~~ the ~~same,~~Zika ~~after deducting underwriting discounts and commissions and estimated offering expenses payable by us~~virus..

~~We currently~~The ~~intend~~occurrence of a pandemic, epidemic, or outbreak of an infectious disease, including, but not limited to, ~~use~~COVID-19, the ~~net~~severe ~~proceeds~~acute ~~from~~respiratory ~~this~~syndrome, ~~offering~~the toH5N1 ~~support~~strain of avian influenza, the ~~clinical~~H1N1 strain of swine flu, and ~~preclinical~~the ~~development~~Zika virus, is highly uncertain and cannot be predicted with confidence, including the duration, scope, and severity of such event. These severe conditions may cause us and our ~~product~~business ~~candidates,~~partners to ~~conduct~~make ~~clinical~~adjustments, ~~trials~~such as temporarily closing down business, ~~including studies~~limiting ~~with~~business hours, and setting restrictions on travel. In regions where we have concentrations of clinical trial sites or other business activities, our ~~bivalent~~business ~~norovirus~~could ~~vaccine~~be adversely affected by health epidemics, towhich ~~support~~could cause significant disruption in the ~~manufacturing~~operations of ~~our~~third-party ~~vaccines~~contract manufacturers and contract research organizations upon whom we rely, as well as our ability to ~~advance~~recruit patients for our ~~therapeutic~~clinical ~~HPV~~trials. ~~vaccine~~Any ~~candidate,~~of ~~and~~the ~~for~~forgoing ~~general~~disruptions ~~corporate~~to ~~and~~our ~~working~~business ~~capital~~can ~~purposes. Accordingly,~~result wein ~~retain~~material ~~broad~~adverse ~~discretion~~effects to ~~use~~our offinancial ~~these~~condition ~~proceeds.~~and results of operations.

~~Pending~~ The outbreak and any preventative or protective actions that governments or we may take in respect of any epidemic may result in a period of business disruption and reduced operations. Any resulting financial impact cannot be reasonably estimated at this time but may materially affect our business, financial condition and results of operations. The extent to which an epidemic impacts our results will depend on future developments, which are highly uncertain and cannot be predicted, including new information which may emerge concerning the ~~use~~severity of an epidemic and the ~~net~~actions ~~proceeds~~to ~~from~~contain ~~this~~the ~~offering~~epidemic or treat its impact, weamong ~~intend~~others. There may be interruptions to ~~invest~~our supply chain due to the ~~net~~inability ~~proceeds~~of manufacturers to continue normal business operations and to ship products. In addition, a significant outbreak of an infectious disease could result in ~~investment-grade~~a widespread health crisis that could adversely affect the economies and financial markets worldwide, ~~interest-bearing~~resulting ~~instruments~~in an economic downturn that could impact our business, financial condition and results of operations. We are currently working to enhance our business continuity plans to include measures to protect our employees in the event of infection in our corporate offices, or in response to potential mandatory quarantines.

Ongoing military conflicts could cause geopolitical instability, economic uncertainty, financial markets volatility and capital markets disruption may adversely affect our revenue, financial condition, or results of operations.

Current military conflicts may disrupt or otherwise adversely impact our operations and those of third parties upon which we rely. Related sanctions, export controls or other actions that have already been initiated or may in the future be initiated by nations including the U.S., the European Union or Russia (e.g., potential cyberattacks, disruption of energy flows, etc.) can adversely affect our business, our contract research organizations, contract manufacturing organizations and other third parties with which we conduct business. Resulting volatility, disruption, or deterioration in the credit and financial markets may further make any necessary debt or equity financing more difficult and more costly. Failure to secure any necessary financing in a timely manner and on favorable terms could have a material adverse effect on our growth strategy, financial performance and stock price and could require us to delay or abandon clinical development plans. In addition, there is a risk that one or more of our current service providers, manufacturers and other partners may be adversely impacted by deteriorating economic conditions, which could directly affect our ability to attain our operating goals and to accurately forecast and plan our future business activities.

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If we ~~DIVIDEND~~fail ~~POLICY~~ to obtain or maintain adequate reimbursement and insurance coverage for our product candidates, our ability to generate significant revenue could be limited.

WeThe ~~have~~availability ~~never~~and ~~paid~~extent orof ~~declared~~reimbursement ~~any~~by ~~cash~~governmental ~~dividends~~and onprivate ~~our~~payors ~~common~~is ~~stock.~~essential Wefor domost ~~not~~patients ~~anticipate~~to ~~paying~~be ~~any~~able ~~cash~~to ~~dividends~~afford onexpensive treatments. Sales of any of our ~~common~~product ~~stock~~candidates inthat ~~the foreseeable~~receive ~~future,~~marketing ~~and~~approval wewill ~~intend~~depend tosubstantially, ~~retain~~both ~~all~~in ~~available~~the ~~funds~~U.S. and ~~any~~internationally, ~~future~~on ~~earnings~~the extent to ~~fund~~which the ~~development~~costs ~~and expansion~~ of our ~~business.~~product Incandidates ~~addition,~~will ~~covenants~~be inpaid ~~the~~by ~~agreement~~health ~~governing~~maintenance, ~~our senior~~managed ~~secured~~care, ~~credit~~pharmacy ~~facility~~benefit doand ~~not~~similar ~~allow~~healthcare ~~for~~management ~~the~~organizations, ~~payment~~or ofreimbursed ~~any~~by ~~cash~~government ~~dividends.~~health ~~Any~~administration ~~future~~authorities, ~~determination~~private tohealth ~~pay~~coverage ~~dividends~~insurers ~~will~~and beother atthird-party ~~the~~payors. ~~discretion~~If ofreimbursement ~~our~~is ~~board~~not ofavailable, ~~directors~~or ~~and~~is ~~will~~available ~~depend~~only ~~upon~~on a ~~number~~ oflimited ~~factors~~basis, ~~including~~we may not be able to successfully commercialize our ~~results~~product ofcandidates. ~~operations,~~Even ~~financial~~if ~~condition,~~coverage ~~future~~is ~~prospects~~provided, ~~contractual~~the ~~restrictions,~~approved ~~restrictions~~reimbursement ~~imposed~~amount bymay ~~applicable~~not ~~law~~be ~~and~~high ~~other~~enough ~~factors~~to ~~our~~allow ~~board~~us ofto ~~directors deems~~establish ~~relevant.~~or maintain adequate pricing that will allow us to realize a sufficient return on our investment.

Outside the U.S., international operations are generally subject to extensive governmental price controls and other market regulations, and we believe the increasing emphasis on cost-containment initiatives in Europe, Canada and other countries may cause us to price our product candidates on less favorable terms that we currently anticipate. In many countries, particularly the countries of the European Union, the prices of medical products are subject to varying price control mechanisms as part of national health systems. In these countries, pricing negotiations with governmental authorities can take considerable time after the receipt of marketing approval for a product. To obtain reimbursement or pricing approval in some countries, we may be required to conduct a clinical trial that compares the cost-effectiveness of our product candidates to other available therapies. In general, the prices of products under such systems are substantially lower than in the U.S. Other countries allow companies to fix their own prices for products but monitor and control company profits. Additional foreign price controls or other changes in pricing regulation could restrict the amount that we are able to charge for our product candidates. Accordingly, in markets outside the U.S., the level of reimbursement for our products is likely to be reduced compared with the U.S. and may be insufficient to generate commercially reasonable revenues and profits.

Moreover, increasing efforts by governmental and third-party payors, in the U.S. and internationally, to cap or reduce healthcare costs may cause such organizations to limit both coverage and level of reimbursement for newly approved products and, as a result, they may not cover or provide adequate payment for our product candidates. We expect to experience pricing pressures in connection with the sale of any of our product candidates due to the trend toward managed healthcare, the increasing influence of health maintenance organizations and additional legislative changes. The downward pressure on healthcare costs in general, particularly prescription drugs and surgical procedures and other treatments, has become very intense. As a result, increasingly high barriers are being erected to the entry of new products into the healthcare market.

Our future success depends on our ability to retain executive officers and attract, retain and motivate qualified personnel.

We rely on our executive officers and the other principal members of the executive and scientific teams. The employment of our executive officers is at-will and our executive officers may terminate their employment at any time. The loss of the services of any of our senior executive officers could impede the achievement of our research, development and commercialization objectives. We do not maintain “key person” insurance for any executive officer or employee.

Recruiting and retaining qualified scientific, clinical and sales and marketing personnel is also critical to our success. We may not be able to attract and retain these personnel on acceptable terms given the competition among numerous pharmaceutical and biotechnology companies for similar personnel. We also experience competition for the hiring of scientific and clinical personnel from universities and research institutions. Our industry has experienced an increasing rate of turnover of management and scientific personnel in recent years. In addition, we rely on consultants and advisors, including scientific and clinical advisors, to assist us in devising our research and development and commercialization strategy. Our consultants and advisors may be employed by third parties and have commitments under consulting or advisory contracts with other entities that may limit their availability to advance our strategic objectives. If any of these advisors or consultants can no longer dedicate a sufficient amount of time to us, our business may be harmed.

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We will ~~CAPITALIZATION~~ need to expand our organization, and may experience difficulties in managing this growth, which could disrupt operations.

~~The~~Our ~~following~~future ~~table~~financial ~~shows~~performance and our ~~cash~~ability to commercialize our product candidates, continue to earn royalties and ~~cash~~compete ~~equivalents~~effectively will depend, in part, on our ability to effectively manage any future growth. As of December 31, 2025, we had 65 employees, which we believe would be insufficient to commercialize our vaccine product candidates. We may have operational difficulties in connection with identifying, hiring and integrating new personnel. Future growth would impose significant additional responsibilities on our ~~capitalization~~management, including the need to identify, recruit, maintain, motivate and integrate additional employees, consultants and contractors. Also, our management may need to divert a disproportionate amount of its attention away from our day-to-day activities and devote a substantial amount of time to managing these growth activities. We may not be able to effectively manage the expansion of our operations, which may result in weaknesses in our infrastructure, give rise to operational mistakes, loss of business opportunities, loss of employees and reduced productivity among remaining employees. Our expected growth could require significant capital expenditures and may divert financial resources from other projects, such as the development of ~~June 30~~our product candidates. If we are unable to effectively manage our growth, ~~2019 on:~~our expenses may increase more than expected, our ability to generate and/or grow revenues could be reduced, and we may not be able to implement our business strategy.

	As of June 30, 2019
	Actual			As Adjusted(1)
	(in thousands, except share and per share data)
Cash and cash equivalents	$	16,258		$



Long-term debt, including current portion	$	18,511		$	18,511
Stockholders' equity:
Preferred stock, $0.10 par value, 5,000,000 shares authorized, no shares issued and outstanding, actual and as adjusted		—			—
Common stock, $0.10 par value, 100,000,000 shares authorized, 15,785,735 shares issued and outstanding, actual; shares issued and outstanding, as adjusted		1,579
Additional paid-in capital		119,258
Accumulated other comprehensive income		—			—
Accumulated deficit		(104,992	)

Total stockholders' equity		15,845

Total capitalization	$	34,356		$

Many of the other pharmaceutical companies that we compete against for qualified personnel and consultants have greater financial and other resources, different risk profiles and a longer history in the industry than us. They may also provide more diverse opportunities and better chances for career advancement. Some of these characteristics may be more appealing to high-quality candidates and consultants than what we are able to offer. If we are unable to continue to attract and retain high-quality personnel and consultants, the rate and success at which we can select and develop our product candidates and our business will be limited.

We ~~(1)A $0.25~~are ~~increase~~subject ~~(decrease)~~to incertain ~~the~~legal ~~assumed~~proceedings, ~~combined public offering price of $ per share of common stock~~ and ~~accompanying~~may ~~common~~be ~~warrant~~subject ~~(the~~to ~~last reported sale price of our common stock on the Nasdaq Capital Market on , 2019), would increase (decrease) each of cash and cash equivalents,~~ additional ~~paid-in~~legal ~~capital~~proceedings, ~~total stockholders'~~which ~~equity~~may ~~and~~result total capitalization by $ million, assuming that the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same, after deducting underwriting discounts and commissions and estimated offering expenses payable by us. An increase (decrease) of 1.0 million shares in ~~the~~substantial ~~number of shares of common stock offered by us would increase (decrease) each of cash and cash equivalents~~costs, ~~additional~~divert ~~paid-in~~management’s ~~capital,~~attention ~~total stockholders' equity~~ and ~~total~~have ~~capitalization~~a bymaterial ~~$ million,~~adverse ~~assuming that~~effect ~~the~~on ~~assumed~~our ~~combined public offering price of $ per share of common stock and accompanying warrant remains the same~~business, ~~after~~financial ~~deducting~~condition ~~underwriting discounts~~ and ~~commissions and~~results ~~estimated offering expenses payable by us. The as adjusted information discussed above is illustrative only and will be adjusted based on the actual public offering price and other terms~~ of ~~this offering determined at pricing~~operations.

We are currently subject to certain pending legal proceedings, as described in this document. We may become involved in additional legal proceedings relating to the aforementioned matters or, from time to time, we may become involved in legal proceedings involving unrelated matters. Due to the inherent uncertainties in legal proceedings, we cannot accurately predict their ultimate outcome. Our stock price has been extremely volatile, and we may become involved in additional securities class action lawsuits in the future. Any such legal proceedings, regardless of their merit, could result in substantial costs and a diversion of management’s attention and resources that are needed to successfully run our business, could impair the Company’s ability to recruit and retain directors, officers, and other key personnel, could impact its ability to secure financing, insurance, and other transactions (or the terms of any such financings, insurance, or other transactions), and for these and other reasons could have a material adverse impact on our business, financial condition, results of operations, and prospects.

If securities or industry analysts do not publish research, or publish inaccurate or unfavorable reports about our business, our stock price and trading volume could decline.

The trading market for our common stock is influenced by independent research and reports that securities or industry analysts publish about us or our business from time to time. If one or more of the analysts who cover us should downgrade our shares or change their opinion of our business prospects, our share price would likely decline.

In light of the COVID-19 pandemic, it is possible that one or more government entities may take actions that directly or indirectly have the effect of abrogating some of our rights or opportunities. If we were to develop a COVID-19 vaccine, the economic value of such a vaccine to us could be limited.

Various government entities, including the U.S. government, are offering incentives, grants and contracts to encourage additional investment by commercial organizations into preventative and therapeutic agents against coronavirus, which may have the effect of increasing the number of competitors and/or providing advantages to known competitors. Accordingly, there can be no assurance that we will be able to successfully establish a competitive market share for our COVID-19 vaccine, if any.

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~~The number~~We ofare ~~shares~~a ofsmaller ~~common~~reporting ~~stock~~company inand the ~~table~~reduced ~~above~~disclosure ~~excludes:~~requirements applicable to smaller reporting companies may make our common stock less attractive to investors.

We are currently a “smaller reporting company” as defined in the Exchange Act. Smaller reporting companies are able to provide simplified executive compensation disclosures in their filings and have certain other decreased disclosure obligations in their SEC filings. We cannot predict whether investors will find our common stock less attractive because of our reliance on the smaller reporting company exemption. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile.

Risks Related to Clinical Development, Regulatory Approval and Commercialization

There are currently no approved vaccines for the prevention of norovirus-related illness. Therefore, the regulatory pathway for any approval of a norovirus vaccine is not entirely clear and may result in unexpected or unforeseen challenges.

As there are currently no vaccines for the prevention of norovirus that are approved by the FDA or another regulatory agency, the regulatory pathway for any approval of a norovirus vaccine is not entirely clear and may result in unexpected or unforeseen challenges. Successful discovery and development of a norovirus vaccine is highly uncertain and dependent on numerous factors, many of which are beyond our control. Our development of the vaccine is in early stages, and we may be unable to produce a vaccine that successfully treats the virus in a timely manner, if at all. Results from clinical testing may raise new questions and require us to redesign proposed clinical trials, including revising proposed endpoints or adding new clinical trial sites or cohorts of subjects. In addition, the FDA’s analysis of clinical data may differ from our interpretation and the FDA may require that we conduct additional analyses.

The regulatory pathway for COVID-19 vaccines is evolving and may result in unexpected or unforeseen challenges.

The speed at which all parties are acting to create and test therapeutics and vaccines for COVID-19 is unusual, and evolving or changing plans or priorities within the FDA, including changes based on new knowledge of COVID-19 and how the disease affects the human body, may significantly affect the regulatory timeline for COVID vaccine candidates. Results from clinical testing may raise new questions and require us to redesign proposed clinical trials, including revising proposed endpoints or adding new clinical trial sites or cohorts of subjects. Results from our vaccine (and other COVID-19) trials may require us to perform additional preclinical studies in order to advance our vaccine candidates. Discussions with FDA regarding the design of the anticipated Phase 2 and 3 studies for COVID-19 vaccine candidates are ongoing and important aspects of the trial design have yet to be determined, including the number of patients to be enrolled, the specific endpoints of the trial and the methods for obtaining and testing samples in the trial. The incidence of COVID-19 in the communities where our studies might be conducted will vary across different locations. If the overall incidence of COVID-19 in those locations is low, it may be difficult for us to recruit subjects or for any study we might perform to demonstrate differences in infection rates between participants in the study who receive placebo and participants in the study who receive COVID-19 vaccine candidates. The availability of other authorized vaccines may decrease the population of clinical trial subjects willing to participate in our future trials.

The FDA has the authority to grant an Emergency Use Authorization to allow unapproved medical products to be used in an emergency to diagnose, treat, or prevent serious or life-threatening diseases or conditions when there are no adequate, approved, and available alternatives. If we are granted an Emergency Use Authorization for COVID-19 vaccine candidates, we would be able to commercialize the vaccine candidate prior to FDA approval. Furthermore, the FDA may revoke an Emergency Use Authorization where it is determined that the underlying health emergency no longer exists or warrants such authorization, and we cannot predict how long, if ever, an Emergency Use Authorization would remain in place. Such revocation could adversely impact our business in a variety of ways, including if the vaccine candidate is not yet approved by the FDA and if we and our manufacturing partners have invested in the supply chain to provide the vaccine candidate under an Emergency Use Authorization.

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In addition, ~~DILUTION~~ any success in preclinical testing we might observe for our COVID-19 vaccine candidates may not be predictive of the results of later-stage human clinical trials. Factors such as efficacy, immunogenicity, and adverse events can emerge at any time in clinical testing and have the potential to have adverse consequences for our ability to proceed with clinical trials. Other factors such as manufacturing challenges, availability of raw materials, and slowdowns in the global supply chain may delay or prevent us from receiving regulatory approval of our vaccine candidate or, if we do receive regulatory approval, prevent a successful product launch. We may not be successful in developing a vaccine, or another party may be successful in producing a more efficacious vaccine or other treatment for COVID-19.

IfEvolving ~~you~~dynamics ~~purchase securities~~ in ~~this offering, your interest will be diluted to~~ the ~~extent~~market offor the difference between the combined public offering price per share and the as adjusted net tangible book value (deficit) per share of our common stock after this offering, assuming no value is attributed to the preCOVID-~~funded~~19 ~~warrants,~~vaccines ~~and such pre-funded warrants~~ are ~~accounted~~likely ~~for~~to ~~and~~impact ~~classified~~our asfinancial ~~equity~~results.

As With the global transition of ~~June 30~~COVID-19 from pandemic to endemic, ~~2019~~the commercial market for COVID-19 vaccines is facing several challenges, ~~our~~including ~~net~~a ~~tangible~~more ~~book~~fragmented ~~value~~customer ~~(deficit)~~base, ~~was~~less ~~$(2.1)~~predictability ~~million~~in orders, greater seasonality of demand, increased distribution costs, and higher costs of goods sold due to single-dose or ~~$(0~~lower-dose presentations.~~13)~~ ~~per~~Such ~~share~~factors could impact the potential market for our COVID-19 vaccine, if approved. ~~Net~~Further, ~~tangible~~our ~~book~~continued ~~value~~development ~~(deficit)~~efforts ~~per~~for ~~share~~our isCOVID-19 ~~total~~vaccine ~~tangible~~could ~~assets~~face ~~less total~~increased ~~liabilities~~research ~~divided~~and bydevelopment ~~the~~costs, ~~total~~including ~~number~~for ofclinical ~~outstanding~~trials, ~~shares~~when ofupdating ~~common~~COVID-19 ~~stock.~~vaccines for new variants of concern.

~~After giving~~If ~~effect~~we fail to ~~the~~continue ~~sale~~to ~~of shares~~develop ~~of common stock~~ and ~~accompanying~~refine ~~common warrants, in this offering at an assumed combined public offering price of $ per share and accompanying common warrant (~~the ~~last~~formulations ~~reported sale price~~ of our ~~common~~tablet ~~stock~~vaccine ~~on the Nasdaq Capital Market on~~ candidates, ~~2019),~~we ~~after~~may ~~deducting~~not ~~underwriting discounts~~obtain ~~and~~regulatory ~~commissions~~approvals, and ~~estimated~~even ~~offering~~if ~~expenses payable by us~~approved, ~~our~~the ascommercial ~~adjusted~~acceptance ~~net tangible book value as~~ of June 30, 2019, would have been $ million, or $ per share. This represents an immediate increase in as adjusted net tangible book value of $ per share to our ~~existing~~tablet ~~stockholders~~vaccine ~~and~~candidates ~~immediate~~would ~~dilution~~likely inbe ~~net tangible book value of $ per share to investors participating in this offering~~limited. ~~The following table illustrates this dilution per share to investors participating in this offering:~~

Assumed combined public offering price per share and accompanying common warrant				$
Net tangible book value (deficit) per share as of June 30, 2019	$	(0.13	)
Increase in as adjusted net tangible book value per share attributable to new investors in this offering

As adjusted net tangible book value per share after giving effect to this offering

Dilution in net tangible book value per share to new investors in this offering				$

In our H1N1 influenza Phase 2 trial we used vaccine tablets that contained approximately 1.5 x 1010 IU of vaccine. Accordingly, subjects in this trial were required to take seven tablets in a single setting to reach the aggregate dose of 1 x 1011 IU, the target dose for this trial. We believe that in order to fully capture the commercial success of our seasonal influenza vaccine candidate, we will need to continue to refine our formulation and develop influenza vaccine tablets that contain the desired dose for each vaccine strain in a single tablet, resulting in a vaccination regime of no more than three tablets. Increasing the potency of the vaccine tablets may affect the stability profile of the vaccine and we may not be able to reduce the vaccination regime for an influenza strain to a single tablet or combine the three influenza strains into one vaccine tablet. In addition, increasing the potency of the vaccine tablets or combining the influenza strains necessary to create a trivalent vaccine may adversely affect manufacturing yields and render such tablets too costly to manufacture at commercial scale. Our efforts to develop tablet vaccine candidates for norovirus face similar formulation challenges. If we are unable to further develop and refine the formulations of our tablet vaccine candidates, we may be unable to obtain regulatory approval from the FDA or other regulatory authorities, and even if approved, the commercial acceptance of our tablet vaccine candidates would likely be limited.

~~Each $0.25~~Clinical ~~increase~~trials ~~(decrease)~~are invery ~~the assumed combined public offering price of $ per share of common stock and accompanying common warrant would increase (decrease)~~expensive, ~~respectively,~~ ~~our as adjusted net tangible book value after this offering by $ per share~~time-consuming, ~~and~~difficult ~~dilution per share~~ to ~~new investors~~design byand ~~$ per~~implement ~~share, assuming that the number of shares of common stock offered by us, as set forth above, remains the same, after deducting underwriting discounts~~ and ~~commissions and~~ ~~estimated~~involve ~~offering~~an ~~expenses~~uncertain payable by us. We may also increase or decrease the number of shares of common stock we are offering. An increase of 1.0 million shares of common stock in the number of shares of common stock offered by us would increase our as adjusted net tangible book value after this offering by $ per shareoutcome, and ~~dilution~~if ~~per~~they ~~share~~fail to ~~new~~demonstrate ~~investors would decrease~~safety ~~by $ per share, assuming that the assumed public offering price remains the same after deducting underwriting discounts~~ and ~~commissions~~efficacy and estimated offering expenses payable by us. A decrease of 1.0 million shares of common stock in the number of shares of common stock offered by us would decrease our as adjusted net tangible book value after this offering by $ per share, and dilution per share to ~~new investors would increase by $ per share, assuming that~~ the ~~assumed~~ ~~combined~~satisfaction ~~public offering price per share~~ of ~~common stock and accompanying common warrant remains~~ the ~~same~~FDA, ~~after~~or ~~deducting~~similar ~~underwriting~~regulatory ~~discounts~~authorities, ~~and~~we ~~commissions~~will ~~and~~be ~~estimated~~unable ~~offering~~to ~~expenses~~commercialize ~~payable~~our bytablet ~~us.~~vaccine candidates.

~~The information~~Our ~~discussed~~tablet ~~above~~vaccine iscandidates ~~illustrative~~for ~~only~~norovirus, coronavirus and influenza are still in early-stage clinical development. Our vaccine candidates will ~~adjust~~require ~~based~~extensive onadditional ~~the~~clinical ~~actual~~testing ~~combined~~before ~~public~~we ~~offering~~are ~~price~~prepared to submit a BLA for regulatory approval for either indication or for any other treatment regime. Such testing is expensive and time-consuming and requires specialized knowledge and expertise. We cannot predict with any certainty if or when we might submit a BLA for regulatory approval for any of our tablet vaccine candidates, which are currently in clinical development, or whether any such BLAs will be approved by the ~~common~~FDA. ~~stock~~Human clinical trials are very expensive and ~~accompanying~~difficult ~~warrant~~to design and implement, in part because they are subject to rigorous regulatory requirements. For instance, the ~~actual~~FDA ~~number~~may not agree with our proposed endpoints for any clinical trial we propose, which may delay the commencement of ~~shares~~ our clinical trials. The clinical trial process is also time-consuming. We estimate that the clinical trials we ~~offer~~need to conduct to be in ~~this~~a ~~offering~~position to submit BLAs for our tablet vaccine candidates for norovirus, coronavirus and ~~other~~influenza ~~terms~~will oftake ~~this~~several ~~offering~~years ~~determined~~to complete. Furthermore, failure can occur at ~~pricing.~~any ~~The~~stage ~~discussion~~of the trials, and ~~table~~we ~~above~~could ~~assume~~encounter ~~(i) no~~problems ~~sale~~that ofcause ~~pre-funded~~us ~~warrants,~~to ~~which,~~abandon ifor ~~sold,~~repeat ~~would reduce~~clinical trials. Our vaccine candidates in the ~~number~~later stages of ~~shares~~clinical trials may fail to show the desired safety and efficacy traits despite having progressed through preclinical studies and initial clinical trials. Also, the results of ~~common~~early ~~stock~~clinical ~~that~~trials weof ~~are~~the ~~offering~~tablet onvaccine acandidates ~~one-~~for~~-one~~ ~~basis~~norovirus, ~~(ii) no~~coronavirus ~~exercise~~and influenza may not be predictive of the ~~underwriter's~~results ~~option~~of subsequent clinical trials. Furthermore, the FDA may impose additional requirements to ~~purchase~~conduct uppreclinical studies to ~~an additional shares~~advance the HPV therapeutic vaccine candidates which could delay initiation of ~~common~~ ~~stock~~Phase ~~and/~~1 studies. A number of companies in the biopharmaceutical industry have suffered significant setbacks in advanced clinical trials due to lack of efficacy or adverse safety profiles, notwithstanding promising results in earlier trials.

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~~common warrants~~Moreover, preclinical and clinical data are often susceptible to ~~purchase~~multiple upinterpretations and analyses. Many companies that have believed their vaccine candidates performed satisfactorily in preclinical studies and clinical trials have nonetheless failed to anobtain ~~additional shares~~marketing approval of ~~our~~their ~~common~~products. ~~stock~~Additionally, success in preclinical testing and ~~(iii) no~~early ~~exercise~~clinical trials does not ensure success in later clinical trials, which involve many more subjects and, for influenza, all three strains rather than the one strain we have studied in Phase 1 clinical trials to date. Accordingly, the results of ~~common warrants~~later ~~accompanying~~clinical trials may not replicate the ~~shares~~results of ~~common~~prior ~~stock~~clinical trials and ~~pre-funded warrants,~~preclinical iftesting ~~any,~~or ~~sold~~may be interpreted in ~~this~~a ~~offering.~~way that may not be sufficient for marketing approval.

~~If the~~We ~~underwriters~~may ~~exercise~~experience innumerous ~~full~~unforeseen ~~their~~events option to purchase up to additional shares of common stock together with accompanying common warrants to purchase up to an additional shares of common stockduring, ~~our~~or as ~~adjusted~~a ~~net~~result ~~tangible book value after this offering would be $ per share~~of, ~~representing~~clinical antrials ~~increase~~that incould asdelay ~~adjusted~~or ~~net~~prevent ~~tangible book~~our ~~value~~ability ~~of $ per share~~ to ~~existing~~receive ~~stockholders~~marketing ~~and~~approval ~~immediate~~or ~~dilution~~commercialize inour ~~net~~tablet ~~tangible~~vaccine ~~book~~candidates, ~~value~~including ~~of $ per share to new investors in this offering.~~ that:

~~If investors~~● inregulators ~~this~~or ~~offering~~institutional ~~exercise~~review inboards ~~full the common warrants for shares of common stock offered hereby for cash at an assumed exercise price of $ per share~~ (~~the~~“IRBs”) ~~last~~may ~~reported~~delay ~~sale~~or ~~price~~not ofauthorize ~~our~~us ~~common~~or ~~stock on the Nasdaq Capital Market on , 2019),~~ our ~~as adjusted~~investigators ~~net~~to ~~tangible~~commence ~~book~~a ~~value~~clinical ~~after~~trial ~~this~~or ~~offering~~conduct ~~would~~a beclinical ~~$ per~~trial ~~share,~~at ~~representing~~a anprospective ~~increase~~trial ~~in as adjusted net tangible book value of $ per share and immediate dilution in net tangible book value of $ per share to new investors in this offering.~~ site;

~~The number~~● ofwe ~~shares~~may ofexperience ~~common~~delays ~~stock~~in toreaching beor ~~outstanding~~fail ~~after~~to ~~this~~reach ~~offering~~agreement ison ~~based~~acceptable onclinical ~~15,785,735~~trial ~~shares~~contracts ofor ~~common~~clinical ~~stock~~trial ~~outstanding~~protocols aswith ofprospective ~~June 30,~~trial ~~2018,~~sites ~~and excludes:~~or CROs;

●	clinical trials of our tablet vaccine candidates may produce negative or inconclusive results, and we may decide, or regulators may require us, to conduct additional clinical trials or abandon product development programs;

●	the number of subjects required for clinical trials of our tablet vaccine candidates may be larger than we anticipate; enrollment in these clinical trials may be slower than we anticipate, or participants may drop out of these clinical trials at a higher rate than we anticipate;

●	our third-party contractors may fail to comply with regulatory requirements or meet their contractual obligations to us in a timely manner, or at all;

●	regulators or IRBs may require that we or our investigators suspend or terminate clinical research for various reasons, including noncompliance with regulatory requirements or a finding that the participants are being exposed to unacceptable health risks;

●	the cost of clinical trials of our tablet vaccine candidates may be greater than we anticipate; and

●	the supply or quality of our tablet vaccine candidates or other materials necessary to conduct clinical trials may be insufficient or inadequate.

If we are required to conduct additional clinical trials or other testing of our tablet vaccine candidates beyond those that we currently contemplate, if we are unable to successfully complete clinical trials of our tablet vaccine candidates or other testing, if the results of these trials or tests are not positive or are only modestly positive or if there are safety concerns, we may:

●	be delayed in obtaining marketing approval for our tablet vaccine candidates;

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● not ~~PRINCIPAL~~obtain ~~STOCKHOLDERS~~ marketing approval at all;

~~The~~● ~~following~~obtain ~~table~~approval ~~sets~~for ~~forth,~~indications asor ofpatient ~~June 30,~~populations ~~2019,~~that ~~information~~are ~~regarding~~not ~~beneficial~~as ~~ownership~~broad ofas ~~our~~intended ~~common~~or ~~stock by:~~desired;

~~Beneficial ownership~~● isobtain ~~determined~~approval ~~according~~with tolabeling ~~the rules of the SEC and generally means~~ that aincludes ~~person~~significant ~~has~~use ~~beneficial ownership of a security if he, she~~ or itdistribution ~~possesses~~restrictions ~~sole~~ or ~~shared voting~~safety ~~or investment power of that security~~warnings, including ~~options~~boxed and warrants that are currently exercisable or exercisable within 60 days of June 30, 2019. Except as indicated by the footnotes below, we believe, based on the information furnished to us, that the persons named in the table below have sole voting and investment power with respect to all shares of common stock shown that they beneficially own. warnings;

~~Our calculation~~● of the percentage of beneficial ownership before this offering is based on 15,785,735 shares of our common stock outstanding as of June 30, 2019. We have based our calculation of the percentage of beneficial ownership after this offering on shares of our common stock to be ~~outstanding~~subject immediately after the closing of this offering, assuming no exercise of the pre-funded warrants, the common warrants or the representative warrants, and assuming no exercise by the underwriters of their option to ~~purchase~~ additional ~~shares~~post-marketing ~~and/or~~testing ~~common warrants.~~requirements; or

~~Common stock~~● ~~subject~~have ~~to stock options, pre-funded warrants and common warrants currently exercisable or exercisable within 60 days of June 30, 2019, are deemed to be outstanding for computing~~ the ~~percentage~~product ~~ownership~~removed offrom the ~~person~~market ~~holding~~after ~~these~~obtaining ~~options~~marketing ~~and the percentage ownership of any group of which the holder is a member but are not deemed outstanding for computing the percentage of any other person~~approval.

Product development costs will also increase if we experience delays in testing or in receiving marketing approvals. We do not know whether any clinical trials will begin as planned, will need to be restructured or will be completed on schedule, or at all. Significant clinical trial delays also could shorten any periods during which we may have the exclusive right to commercialize our tablet vaccine candidates, could allow our competitors to bring products to market before we do, and could impair our ability to successfully commercialize our tablet vaccine candidates, any of which may harm our business and results of operations.

A resurgence of the COVID-19 pandemic or the emergence of another public health emergency/pandemic could adversely impact our preclinical studies and clinical trials.

We have active and planned preclinical studies and clinical trial sites in the U.S.

While both COVID-19 and countermeasures have abated to some degree, there can be no assurance that the COVID-19 pandemic will not cause disruptions to our business development activities, including our clinical trials. In the event of a resurgence of the COVID-19 pandemic or emergence of another public health emergency, we may experience disruptions that could severely impact our planned and ongoing preclinical studies and clinical trials, including preclinical and clinical studies and manufacturing of our vaccine candidates. Effects on our preclinical studies and clinical trial programs include, but are not limited to:

●	delays in procuring subjects in our preclinical studies;

●	delays or difficulties in enrolling patients in our clinical trials;

●	delays or difficulties in preclinical and clinical site initiation, including difficulties in establishing appropriate and safe social distancing and other safeguards at preclinical and clinical sites;

●	diversion of healthcare resources away from the conduct of preclinical and clinical trials, including the diversion of hospitals serving as our clinical trial sites and hospital staff supporting the conduct of our clinical trials;

●

interruption of key preclinical study and clinical trial activities, such as preclinical and clinical trial site monitoring, subject recruitment and subject testing due to the course of the pandemic, limitations on freight and/or travel imposed or recommended by federal or state governments, employers and others;

●

limitations in employee resources that would otherwise be focused on the conduct of our preclinical studies and clinical trials, including because of sickness of employees or their families, delays or difficulties in conducting site visits and other required travel, and the desire of employees to avoid contact with large groups of people;

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~~Unless otherwise~~● ~~noted~~delays ~~below,~~in ~~the~~receiving ~~address~~approval ~~for~~from ~~each~~local ofregulatory ~~the~~authorities ~~stockholders~~to ininitiate ~~the~~or ~~table~~continue ~~below~~our isplanned ~~c/o Vaxart, Inc.,~~preclinical ~~290~~studies ~~Utah~~and ~~Ave,~~clinical ~~Suite 200, South San Francisco, California 94080.~~ trials;

	Shares Beneficially Owned Prior to this Offering					Shares Beneficially Owned After this Offering
Name of Beneficial Owner	Shares		%			Shares	%
Greater than 5% Stockholders:
Entities affiliated with Care Capital(1)		2,799,424		17.73	%
Affiliates of Sabby Management, LLC(2)		791,092		4.99	%
BML Investment Partners, L.P.(3)		900,000		5.70	%
Executive Officers and Directors:
Geoffrey F. Cox, Ph.D.(4)		11,567		*
Margaret A. Echerd(5)		5,333		*
Michael J. Finney, Ph.D.(6)		637,390		4.0	%
Wouter W. Latour, M.D.(7)		125,748		*
Richard J. Markham(8)		3,000		*
John P. Richard(9)		12,543		*
Sean N. Tucker, Ph.D.(10)		193,654		1.2	%
Anne M. VanLent(11)		15,724		*
All executive officers and directors as a group (8 persons)		988,059		6.1	%

●	regulatory or legal developments in the U.S. or other countries; and

● *Represents beneficial ownership of less than one percent. (1)Includes (a) 2,753,441 shares held by Care Capital Investments III, LP ("Investments III") and (b) 45,983 shares held by Care Capital Offshore Investments III, LP ("Offshore III"). Care Capital III LLC is the ~~general~~success ~~partner~~ of ~~Investments~~competitive ~~III LP~~vaccine ~~and~~products ~~Offshore III (collectively, "Care Capital") and as a result, Care Capital III LLC has the ultimate power to vote~~ or direct the vote and to dispose or direct the disposition of such shares. The address for each of these entities is P.O. Box 276, Avon by the Sea, New Jersey 07717. (2)Includes (a) 723,262 shares of common stock and (b) 67,830 shares of common stock issuable on the exercise of preCOVID-~~funded~~19 ~~warrants~~treatments ~~held by Sabby Volatility Warrant Master Fund, Ltd. ("Sabby Warrant"). Sabby Management, LLC ("Sabby Management")~~ and ~~Hal~~related ~~Mintz, who is manager of Sabby Management, beneficially own, and have shared voting and investment powers over all shares owned by Sabby Warrant~~technologies. Does not include shares of common stock issuable on the exercise of 1,578,534 pre-funded warrants and 3,636,364 common warrants held by Sabby Warrant. The provisions of such warrants restrict their exercise to the extent that, after giving effect to such exercise, the holder of the warrants and such holder's affiliates and any other person or entities with which such holder would constitute a group would beneficially own in excess of 4.99% of the number of shares of common stock outstanding immediately after giving effect to such exercise as a result of which such warrants are not currently exercisable. The address for Sabby Management and Mr. Mintz (c/o Sabby Management) is 10 Mountainview Road, Suite 205, Upper Saddle River, NJ 07458 and the address for Sabby Warrant is c/o Ogier Fiduciary Services (Cayman) Limited, 89 Nexus Way, Camana Bay, Grand Cayman KY1-9007, Cayman Islands. This information has been obtained from the Schedule 13G filed by Sabby Warrant, Sabby Management and Mr. Mintz on April 25, 2019. (3)Consists of 900,000 shares held by BML Investment Partners, L.P., a Delaware limited partnership whose sole general partner is BML Capital Management, LLC. The managing member of BML Capital Management, LLC is Braden M.Leonard. As a result, Braden M. Leonard is deemed to be the indirect owner of the shares held directly by BML Investment Partners, L.P. Despite such

If a patient participating in one of our clinical trials contracts COVID-19, this could negatively impact the data readouts from these trials; for example, the patient may be unable to participate further (or may have to limit participation) in our clinical trial, the patient may show a different efficacy assessment than if the patient had not been infected, or such patient could experience an adverse event that could be attributed to our drug product.

The extent to which COVID-19 may impact our preclinical studies and clinical trials will depend on future developments, which remains highly uncertain and cannot be predicted with confidence.

Our platform includes a novel vaccine adjuvant and all of our current tablet vaccine candidates include this novel adjuvant, which may make it difficult for us to predict the time and cost of tablet vaccine development as well as the requirements the FDA or other regulatory agencies may impose to demonstrate the safety of the tablet vaccine candidates.

Novel vaccine adjuvants, included in some of our tablet vaccine candidates, may pose an increased safety risk to patients. Adjuvants are compounds that are added to vaccine antigens to enhance the activation and improve immune response and efficacy of vaccines. Development of vaccines with novel adjuvants requires evaluation in larger numbers of patients prior to approval than would be typical for therapeutic drugs. Guidelines for evaluation of vaccines with novel adjuvants have been established by the FDA and other regulatory bodies and expert committees. Our current tablet vaccine candidates, including for norovirus, include a novel adjuvant, and future vaccine candidates may also include one or more novel vaccine adjuvants. Any vaccine, because of the presence of an adjuvant, may have side effects considered to pose too great a risk to patients to warrant approval of the vaccine. Traditionally, regulatory authorities have required extensive study of novel adjuvants because vaccines typically get administered to healthy populations, in particular infants, children and the elderly, rather than to people with disease. Such extensive study has often included long-term monitoring of safety in large general populations that have at times exceeded 10,000 subjects. This contrasts with the few thousand subjects typically necessary for approval of novel therapeutics. To date, the FDA and other major regulatory agencies have only approved vaccines containing five adjuvants, which makes it difficult to determine how long it will take or how much it will cost to obtain regulatory approvals for our tablet vaccine candidates in the U.S. or elsewhere.

Enrollment and retention of subjects in clinical trials is an expensive and time-consuming process and could be made more difficult or rendered impossible by multiple factors outside our control.

We may encounter delays in enrolling, or be unable to enroll, a sufficient number of participants to complete any of our clinical trials. Once enrolled, we may be unable to retain a sufficient number of participants to complete any of our trials. Late-stage clinical trials of our tablet vaccine candidate for norovirus and coronavirus, in particular, will require the enrollment and retention of large numbers of subjects. Subject enrollment and retention in clinical trials depends on many factors, including the size of the subject population, the nature of the trial protocol, the existing body of safety and efficacy data with respect to the study drug, the number and nature of competing treatments and ongoing clinical trials of competing drugs for the same indication, the proximity of subjects to clinical sites and the eligibility criteria for the study. Further, since there are no reliable animal models to norovirus infection, human challenge studies have been used to understand viral activity and possible immune correlates that prevent infection making trials costlier than animal-based studies.

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~~shared beneficial ownership~~Furthermore, ~~the~~any ~~reporting~~negative ~~persons~~results ~~disclaim~~we ~~that~~may ~~they~~report ~~constitute~~in aclinical ~~statutory~~trials ~~group within the meaning~~ of ~~Rule 13d-5(b)~~our ~~(1) of~~tablet ~~the~~vaccine ~~Exchange~~candidates ~~Act.~~may ~~The~~make ~~address~~it ~~for~~difficult ~~each~~or ~~of these~~impossible ~~entities~~to isrecruit 65and Eretain ~~Cedar—Suite 2,~~participants ~~Zionsville,~~in INother ~~46077.~~clinical ~~This~~trials ~~information~~of ~~has~~that ~~been~~same ~~obtained~~tablet ~~from~~vaccine ~~the~~candidate. ~~Schedule 13G~~Delays ~~filed~~or byfailures ~~BML~~in ~~Investment~~planned ~~Partners, L.P.~~subject ~~on April 17,~~enrollment ~~2019. (4)Includes (a) 388~~or ~~shares~~retention ~~held~~may byresult ~~Dr. Cox's~~in ~~spouse,~~increased ~~and (b) 11~~costs,~~179~~ ~~shares~~program ~~issuable~~delays ~~pursuant~~or toboth, ~~stock~~which ~~options~~could ~~exercisable~~have ~~within~~a ~~60 days~~harmful ~~of June 30,~~effect ~~2019. (5)Consists of~~on ~~5,333~~our ~~shares~~ability ~~issuable pursuant~~ to ~~stock~~develop ~~options~~our ~~exercisable~~tablet ~~within~~vaccine ~~60 days of June 30~~candidates, ~~2019. (6)Includes (a) 452,572~~or ~~shares~~could ~~held~~render ~~directly~~further bydevelopment Drimpossible. ~~Finney,~~ ~~(b) 181,818~~In ~~shares issuable pursuant to common warrants and (c) 3~~addition,~~000~~ ~~shares issuable~~we ~~pursuant~~expect to ~~stock~~rely ~~options~~on ~~exercisable~~CROs ~~within~~and ~~60 days~~clinical oftrial ~~June 30,~~sites ~~2019. (7)Consists of 125,748 shares issuable pursuant~~ to ~~stock~~ensure ~~options~~proper ~~exercisable~~and ~~within~~timely ~~60 days~~conduct of ~~June 30,~~our ~~2019. (8)Consists of~~future ~~3,000~~clinical ~~shares~~trials ~~issuable pursuant to stock options exercisable within 60 days of June 30~~and, ~~2019. (9)Consists of~~while ~~12,543~~we ~~shares~~intend ~~issuable pursuant~~ to ~~stock~~enter ~~options~~into ~~exercisable~~agreements ~~within~~governing ~~60 days~~their ~~of June 30~~services, ~~2019. (10)Includes (a) 47,653~~we ~~shares~~will ~~held~~be ~~directly~~limited byin ~~Dr. Tucker,~~our ~~(b) 52,661~~ability ~~shares~~to ~~held~~compel bytheir ~~Frances~~actual ~~Chang~~performance ~~and~~in ~~Sean~~compliance ~~Tucker,~~with ~~(c) 9,060~~applicable ~~shares held by Dr~~regulations. ~~Tucker's~~ ~~spouse,~~Enforcement ~~(b) 52,661~~actions ~~shares~~brought ~~issuable~~against ~~pursuant~~these tothird ~~common~~parties ~~warrants~~may ~~held~~cause byfurther ~~Frances~~delays ~~Chang~~ and ~~Sean~~expenses ~~Tucker,~~related ~~and (e) 48,609 shares issuable pursuant~~ to ~~stock~~our ~~options exercisable~~clinical ~~within~~development ~~60 days of June 30, 2019~~programs. ~~(11)Includes (a) 3,181 shares held directly by Ms. VanLent, and (b) 12,543 shares issuable pursuant to stock options exercisable within 60 days of June 30, 2019.~~

We face significant competition from other biotechnology and pharmaceutical companies, and our operating results will suffer if we fail to compete effectively.

Vaccine development is highly competitive and subject to rapid and significant technological advancements. We face competition from various sources, including larger and better funded pharmaceutical, specialty pharmaceutical and biotechnology companies, as well as academic institutions, governmental agencies and public and private research institutions. In particular, our COVID-19 and influenza vaccine candidates would compete with products that are available and have gained market acceptance as the standard treatment protocol. Further, it is likely that additional drugs or other treatments will become available in the future for the treatment of the diseases we are targeting.

For tablet vaccines, we face competition from approved vaccines, against which new tablet vaccines must demonstrate compelling advantages in efficacy, convenience, tolerability and safety, and from competitors working to patent, discover, develop or commercialize medicines before we can do the same with tablet vaccines.

Many of our existing or potential competitors have substantially greater financial, technical and human resources than we do and significantly greater experience in the discovery and development of products for the treatment of diseases, as well as in obtaining regulatory approvals of those products in the U.S. and in foreign countries. Our current and potential future competitors also have significantly more experience commercializing drugs that have been approved for marketing. Mergers and acquisitions in the pharmaceutical and biotechnology industries could result in even more resources being concentrated among a small number of our competitors.

Competition may increase further as a result of advances in the commercial applicability of technologies and greater availability of capital for investment in these industries. Our competitors may succeed in developing, acquiring or licensing, on an exclusive basis, drugs that are more effective or less costly than any tablet vaccine candidate that we may develop.

We will face competition from other drugs currently approved or that will be approved in the future for the treatment of the other infectious diseases we are currently targeting. Therefore, our ability to compete successfully will depend largely on our ability to:

●	develop and commercialize tablet vaccine candidates that are superior to other vaccines in the market;

●	demonstrate through our clinical trials that our tablet vaccine candidates are differentiated from existing and future therapies;

●	attract qualified scientific, vaccine development and commercial personnel;

●	obtain patent or other proprietary protection for our tablet vaccine candidates;

●	obtain required regulatory approvals;

●	obtain coverage and adequate reimbursement from, and negotiate competitive pricing with, third-party payors; and

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● successfully ~~DESCRIPTION~~develop OFand ~~CAPITAL~~commercialize, ~~STOCK~~ independently or with collaborators, new tablet vaccine candidates.

The ~~following~~availability ~~summary description~~ of our ~~capital~~competitors’ ~~stock~~vaccines iscould ~~based~~limit on the ~~provisions~~demand, ~~of our amended~~ and ~~restated certificate of incorporation and amended and restated bylaws and~~ the ~~applicable~~price ~~provisions~~we ofare ~~the~~able ~~Delaware General Corporation Law. This information is qualified entirely by reference~~ to ~~the applicable provisions of our amended and restated certificate of incorporation~~charge, ~~bylaws~~for ~~and~~any ~~the~~tablet ~~Delaware~~vaccine ~~General~~candidate ~~Corporation~~we ~~Law~~develop. ~~For~~The ~~information~~inability ~~on how~~ to ~~obtain~~compete ~~copies~~with ofexisting ~~our~~or ~~amended~~subsequently ~~and~~introduced ~~restated certificate~~vaccines ofwould ~~incorporation~~have ~~and~~an ~~bylaws,~~adverse ~~which~~impact ~~are~~on ~~exhibits~~our ~~to the registration statement of which this prospectus is a part~~business, ~~see~~financial ~~the~~condition ~~sections titled "Where You Can Find Additional Information"~~ and ~~"Incorporation~~ ~~of Certain Information by Reference" in this prospectus~~prospects.

~~General~~ Established pharmaceutical companies may invest heavily to accelerate discovery and development of novel compounds or to in-license novel compounds that could make any of our tablet vaccine candidates less competitive. In addition, any new vaccine that competes with an approved vaccine must demonstrate compelling advantages in efficacy, convenience, tolerability and safety in order to overcome price competition and to be commercially successful. Accordingly, our competitors may succeed in obtaining patent protection, discovering, developing, receiving the FDA’s approval for or commercializing medicines before we do, which would have an adverse impact on our business and results of operations.

~~Our~~The ~~authorized~~biotechnology ~~capital~~and ~~stock~~pharmaceutical ~~consists~~industries ofare ~~(i) 100,000,000~~characterized ~~shares~~by ofintense ~~common~~competition ~~stock,~~to ~~par~~develop ~~value~~new $0technologies and proprietary products.10 ~~per~~While ~~share~~we ~~and~~believe ~~(ii) 5~~that our proprietary tablet vaccine candidates provide competitive advantages,~~000~~ we face competition from many different sources,~~000 shares~~ ofincluding ~~preferred~~biotechnology ~~stock~~and pharmaceutical companies, ~~par~~academic ~~value~~institutions, ~~$0.10~~government ~~per~~agencies, ~~share~~as well as public and private research institutions. Any products that we may commercialize will have to compete with existing products and therapies as well as new products and therapies that may become available in the future.

~~As of~~There ~~June 30~~are other organizations working to improve existing therapies, ~~2019~~vaccines or delivery methods, ~~there~~or ~~were~~to 15develop new vaccines,~~785,735~~ ~~shares~~therapies ofor ~~common~~delivery ~~stock~~methods ~~issued~~for ~~and~~their ~~outstanding~~selected indications. Depending on how successful these efforts are, ~~and~~it nois ~~shares~~possible they may increase the barriers to adoption and success of ~~preferred~~our ~~stock~~vaccine ~~outstanding.~~candidates, if approved.

~~The following~~We isanticipate athat ~~summary~~we ofwill ~~the~~face ~~material~~intense ~~provisions~~and ofincreasing competition as new vaccines enter the ~~common~~market ~~stock~~and advanced technologies become available. We expect any tablet or other oral delivery vaccine candidates that we develop and ~~preferred~~commercialize ~~stock~~to ~~provided~~compete ~~for~~on inthe ~~our~~basis ~~amended~~of, among other things, efficacy, safety, convenience of administration and ~~restated~~delivery, ~~certificate~~price, availability of ~~incorporation~~therapeutics, the level of generic competition and ~~amended~~the availability of reimbursement from government and ~~restated~~ ~~bylaws.~~other third-party payors.

~~Common~~Our ~~Stock~~ commercial opportunity could be reduced or eliminated if our competitors develop and commercialize products that are safer, more effective, have fewer or less severe side effects, are more convenient or are less expensive than any products that we may develop. Our competitors also may obtain FDA or other regulatory approval for their products more rapidly than we may obtain approval for our vaccine candidates, which could result in our competitors establishing a strong market position before we are able to enter the market. In addition, our ability to compete may be affected in many cases by insurers or other third-party payors seeking to encourage the use of generic products.

~~Voting~~ As of January 2026, there are no vaccines approved by the FDA or other global regulatory agencies for the prevention of norovirus. We are aware that Moderna, Inc. and Merck, Inc. are developing norovirus vaccines that would be delivered by injection. Other companies reporting development of a norovirus vaccine candidate are Anhui Zhifei Longcom Biopharmaceutical Co. Ltd., Chongqing Zhifei Biological Products Co., Ltd., and the National Vaccine and Serum Institute of China. In addition, we are aware of Cocrystal Pharma, Inc. reporting development of an oral antiviral for norovirus. There may be other development programs that we are not aware of.

~~Our~~There ~~common stock~~ is ~~entitled~~significant tocompetition ~~one~~in ~~vote for each share held of record on all matters submitted to a vote of~~ the ~~stockholders,~~COVID-19 ~~except~~vaccine ~~that directors~~market. ~~will~~Pfizer-BioNTech’s beCOVID-19 ~~elected by a plurality of votes cast. Accordingly~~vaccine, ~~the~~Moderna’s ~~holders~~COVID-19 ofvaccine aand ~~majority~~Novavax’s ofCOVID-19 ~~the~~vaccine ~~shares~~have ofbeen ~~common~~approved ~~stock entitled to vote~~ in ~~any~~the ~~election~~U.S. ofand ~~directors~~many ~~are~~countries ~~able~~around ~~to elect all of~~ the ~~directors~~ ~~standing for election, if they so choose~~world.

Dividends

Subject to preferences that may be applicable to any then outstanding preferred stock, the holders of common stock are entitled to receive dividends, if any, as may be declared from time to time by our board of directors out of legally available funds. We have never paid cash dividends and have no present intention to pay cash dividends.

Liquidation

In the event of a liquidation, dissolution or winding up, holders of our common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all of our debts and other liabilities, subject to the satisfaction of any liquidation preference granted to the holders of any outstanding shares of preferred stock.

Rights and Preferences

Holders of our common stock have no preemptive, conversion or subscription rights, and there are no redemption or sinking fund provisions applicable to our common stock. The rights, preferences and privileges of the holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock that we may designate and issue in the future.

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~~Fully~~Our ~~Paid~~tablet ~~and~~vaccine ~~Nonassessable~~ candidates may cause adverse effects or have other properties that could delay or prevent their regulatory approval or limit the scope of any approved label or market acceptance.

~~All~~Adverse ofevents caused by our ~~outstanding~~tablet ~~shares~~vaccine ofcandidates ~~common~~could ~~stock~~cause ~~are~~reviewing ~~fully~~entities, ~~paid~~clinical trial sites or regulatory authorities to interrupt, delay or halt clinical trials and ~~nonassessable~~could result in the denial of regulatory approval. If an unacceptable frequency or severity of adverse events are reported in clinical trials for our tablet vaccine candidates, our ability to obtain regulatory approval for such tablet vaccine candidates may be negatively impacted.

~~Preferred~~Furthermore, ~~Stock~~ if any of our tablet vaccines are approved and then cause serious or unexpected side effects, a number of potentially significant negative consequences could result, including:

~~Our~~● ~~board~~regulatory ofauthorities ~~directors~~may ~~has~~withdraw ~~the~~their ~~authority,~~approval ~~without further action by the stockholders, to issue up to 5,000,000 shares~~ of ~~preferred stock in one or more series, to establish from time to time~~ the ~~number~~tablet ofvaccine ~~shares~~candidates ~~to be included in each such series, to fix the rights, preferences and privileges of the shares of each wholly unissued series and any qualifications, limitations~~ or impose restrictions ~~thereon~~on ~~and~~their todistribution ~~increase~~ or ~~decrease~~other ~~the~~risk ~~number~~management ~~of shares of any such series, but not below the number of shares of such series then outstanding.~~ measures;

~~Our board~~● ofregulatory ~~directors~~authorities may ~~authorize~~require the ~~issuance~~addition of ~~preferred~~labeling ~~stock with voting or conversion rights that could adversely affect the voting power or other rights of the holders of the common stock. The issuance of preferred stock~~statements, ~~while~~such ~~providing~~as ~~flexibility~~warnings ~~in connection with possible acquisitions and other corporate purposes, could, among other things, have the effect of delaying, deferring~~ or preventing a change in our control that may otherwise benefit holders of our common stock and may adversely affect the market price of the common stock and the voting and other rights of the holders of common stock. As of June 30, 2019, there were no shares of preferred stock outstanding and we have no current plans to issue any shares of preferred stock. contraindications;

~~Anti-Takeover~~● ~~Effects~~we ofmay ~~Provisions~~be ofrequired ~~Our~~to ~~Charter~~change ~~Documents~~the ~~and~~way ~~Delaware~~our ~~Law~~ tablet vaccine candidates are administered or to conduct additional clinical trials;

~~Delaware~~● ~~Anti-Takeover~~we ~~Law~~ could be sued and held liable for injuries sustained by patients;

We● ~~are~~we could be subject to ~~Section 203 of~~ the ~~DGCL,~~Vaccine orInjury ~~Section 203.~~Compensation Section 203 generally prohibits a public Delaware corporation from engaging in a "business combination" with an "interested stockholder" for a period of three years after the date of the transaction in which the person became an interested stockholder, unless:Program;

●	we could elect to discontinue the sale of our tablet vaccine candidates; and

●	our reputation may suffer.

Any of these events could prevent us from achieving or maintaining market acceptance of the affected tablet vaccine candidate and could substantially increase the costs of commercialization.

Disruptions at the FDA and other government agencies caused by funding shortages, staffing limitations or global health concerns could hinder their ability to hire and retain key leadership and other personnel, or otherwise prevent new products and services from being developed or commercialized in a timely manner, which could negatively impact our business.

The ability of the FDA and other government agencies to review and approve new products can be affected by a variety of factors, including government budget and funding levels, statutory, regulatory and policy changes, a government agency’s ability to hire and retain key personnel and accept the payment of user fees, and other events that may otherwise affect the government agency’s ability to perform routine functions. Average review times at the FDA and other government agencies have fluctuated in recent years as a result. In addition, government funding of other government agencies that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable. Disruptions at the FDA and other agencies may also slow the time necessary for new drugs and or modifications to approved drugs or to be reviewed and/or approved by necessary government agencies, which would adversely affect our business. For example, over the last several years, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA, have had to furlough critical FDA employees and stop critical activities. With the change in presidential administrations in 2025, there is substantial uncertainty as to how, if at all, the new administration will seek to modify or revise the requirements and policies of the FDA and other regulatory agencies with jurisdiction over our product candidates. The impending uncertainty could present new challenges or potential opportunities as we navigate the clinical development and approval process for our product candidates.

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~~In general,~~If ~~Section 203~~we ~~defines~~are annot ~~interested~~able ~~stockholder~~to asobtain, ~~any entity~~ or ~~person~~if ~~beneficially~~there ~~owning~~are ~~15%~~delays orin ~~more~~obtaining, ofrequired ~~the~~regulatory ~~outstanding~~approvals, ~~voting~~we ~~stock~~will ofnot ~~the~~be ~~corporation~~able ~~and~~to ~~any~~commercialize, ~~entity~~ or ~~person~~will ~~affiliated~~be ~~with~~delayed orin ~~controlling~~commercializing, orour ~~controlled~~tablet byvaccine ~~the~~candidates, ~~entity~~and orour ~~person.~~ability to generate significant revenue will be impaired.

~~Certificate~~Our tablet vaccine candidates and the activities associated with their development and commercialization, including their design, testing, manufacture, safety, efficacy, recordkeeping, labeling, storage, approval, advertising, promotion, sale and distribution, are subject to comprehensive regulation by the FDA and other regulatory agencies in the U.S. and by comparable authorities in other countries. Failure to obtain marketing approval for a tablet vaccine candidate will prevent us from commercializing the tablet vaccine candidate. We have not received approval to market any of ~~Incorporation~~our tablet vaccine candidates from regulatory authorities in any jurisdiction. We have only limited experience in filing and ~~Bylaws~~ supporting the applications necessary to gain marketing approvals and expect to rely on CROs to assist us in this process. Securing regulatory approval requires the submission of extensive preclinical and clinical data and supporting information to the various regulatory authorities for each therapeutic indication to establish the tablet vaccine candidate’s safety and efficacy. Securing regulatory approval also requires the submission of information about the product manufacturing process to, and inspection of manufacturing facilities by, the relevant regulatory authority. Our tablet vaccine candidates may not be effective, may be only moderately effective or may prove to have undesirable or unintended side effects, toxicities or other characteristics that may preclude us obtaining marketing approval or prevent or limit commercial use.

~~Provisions~~The process of ~~our~~obtaining ~~certificate~~marketing ofapprovals, ~~incorporation~~both in the U.S. and ~~bylaws~~elsewhere, is expensive, may ~~delay~~take many years and can vary substantially based upon a variety of factors, including the type, complexity and novelty of the tablet vaccine candidates involved. We cannot be sure that we will ever obtain any marketing approvals in any jurisdiction. Changes in marketing approval policies during the development period, changes in or ~~discourage~~the ~~transactions~~enactment ~~involving~~of anadditional ~~actual~~statutes or ~~potential change-~~regulations or changes in~~-control~~ regulatory review for each submitted product application may cause delays in the approval or ~~change~~rejection of an application. The FDA and comparable authorities in ~~our~~other ~~management,~~countries ~~including~~have ~~transactions~~substantial discretion in ~~which~~the ~~stockholders~~approval ~~might~~process ~~otherwise~~and ~~receive~~may arefuse ~~premium~~to ~~for~~accept ~~their~~any ~~shares~~application or ~~transactions~~may decide that our ~~stockholders~~data ~~might~~is ~~otherwise deem~~insufficient tofor beapproval inand ~~their~~require ~~best~~additional ~~interests~~preclinical or other studies, and clinical trials. ~~Therefore~~In addition, ~~these~~varying ~~provisions~~interpretations of the data obtained from preclinical testing and clinical trials could ~~adversely~~delay, ~~affect~~limit ~~the~~or ~~price~~prevent marketing approval of ~~our~~a ~~common~~tablet ~~stock~~vaccine candidate. ~~Among~~Additionally, ~~other~~any ~~things,~~marketing ~~our~~approval ~~certificate~~we ofultimately ~~incorporation~~obtain ~~and bylaws:~~may be limited or subject to restrictions or post-approval commitments that render the approved product not commercially viable.

~~Nasdaq~~Even ~~Capital~~if ~~Market~~we ~~Listing~~ obtain FDA approval in the United States, we may never obtain approval for or commercialize our tablet vaccine candidates in any other jurisdiction, which would limit our ability to realize each product’s full market potential.

~~Our~~In ~~common~~order ~~stock~~to ismarket ~~listed~~any of our tablet vaccine candidates in a particular jurisdiction, we must establish and comply with numerous and varying regulatory requirements on a country-by-country basis regarding safety and efficacy. Approval by the ~~Nasdaq~~FDA ~~Capital~~in ~~Market~~the ~~under~~U.S. does not ensure approval by regulatory authorities in other countries or jurisdictions. In addition, clinical trials conducted in one country may not be accepted by regulatory authorities in other countries, and regulatory approval in one country does not guarantee regulatory approval in any other country. Approval processes vary among countries and can involve additional tablet vaccine candidate testing and validation and additional administrative review periods. Seeking foreign regulatory approval could result in difficulties and costs for us and require additional preclinical studies or clinical trials which could be costly and time consuming. Regulatory requirements can vary widely from country to country and could delay or prevent the ~~symbol~~introduction ~~"VXRT~~of our tablet vaccine candidates in those countries." We do not have any tablet vaccine candidates approved for sale in any jurisdiction, including in international markets, and we do not have experience in obtaining regulatory approval in international markets. If we fail to comply with regulatory requirements in international markets or to obtain and maintain required approvals, or if regulatory approvals in international markets are delayed, our target market will be reduced and our ability to realize the full market potential of any tablet vaccine candidate we develop will be unrealized.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is American Stock Transfer & Trust Company, LLC. The transfer agent and registrar's address is 6201 15th Avenue, Brooklyn, New York 11219.

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Even if ~~DESCRIPTION~~we OFobtain ~~SECURITIES~~regulatory WEapproval, ~~ARE~~we ~~OFFERING~~ will still face extensive ongoing regulatory requirements, and our tablet vaccine candidates may face future development and regulatory difficulties.

WeAny ~~are~~tablet ~~offering shares~~vaccine ofcandidate ~~our~~for ~~common~~which ~~stock~~we ~~and/or~~obtain ~~pre~~marketing approval, along with the manufacturing processes, post-~~funded~~approval ~~warrants~~clinical data, labeling, packaging, distribution, adverse event reporting, storage, recordkeeping, export, import, advertising and ~~accompanying~~promotional ~~common~~activities ~~warrants~~for tosuch ~~purchase up~~tablet vaccine candidate, among other things, will be subject to ~~shares~~ extensive and ongoing requirements of ~~our~~and ~~common~~review ~~stock~~by the FDA and other regulatory authorities. ~~Each~~These ~~share~~requirements include submissions of ~~common~~safety, ~~stock~~efficacy orand ~~pre~~other post-~~funded~~marketing ~~warrant~~information isand ~~being~~reports, ~~sold~~establishment ~~together~~registration and drug listing requirements, continued compliance with acurrent ~~common~~Good ~~warrant~~Manufacturing Practice, or cGMP, requirements relating to ~~purchase~~manufacturing, ~~one~~quality ~~share~~control, quality assurance and corresponding maintenance of ~~common~~records ~~stock.~~and ~~The~~documents, ~~shares~~requirements regarding the distribution of ~~common stock~~ samples to physicians and recordkeeping and current good clinical practice, ~~pre~~or GCP, requirements for any clinical trials that we conduct post-~~funded~~approval. ~~warrants~~Even ~~and~~if ~~common~~marketing ~~warrants~~approval ~~will~~of a tablet vaccine candidate is granted, the approval may be ~~issued~~subject ~~separately.~~to Welimitations ~~are~~on ~~also~~the ~~registering~~indicated uses for which the ~~shares~~tablet ofvaccine ~~common~~candidates ~~stock~~may ~~issuable~~be ~~from~~marketed ~~time~~or to ~~time~~the ~~upon~~conditions ~~exercise~~ of approval. If a tablet vaccine candidate receives marketing approval, the ~~pre-funded~~accompanying ~~warrants~~label ~~and common~~may ~~warrants~~limit ~~offered~~the ~~hereby.~~approved use of that tablet vaccine, which could limit sales.

~~Common~~The ~~Stock~~ FDA may also impose requirements for costly post-marketing studies or clinical trials and surveillance to monitor the safety and/or efficacy of our tablet vaccine candidates. The FDA closely regulates the post-approval marketing and promotion of drugs to ensure drugs are marketed only for the approved indications and in accordance with the provisions of the approved labeling. The FDA imposes stringent restrictions on manufacturers’ communications regarding off-label use and if we do not market our tablet vaccine candidates for their approved indications, we may be subject to enforcement action for off-label marketing. Violations of the Federal Food, Drug, and Cosmetic Act relating to the promotion of prescription drugs may lead to FDA enforcement actions and investigations alleging violations of federal and state health care fraud and abuse laws, as well as state consumer protection laws.

~~The~~In ~~material~~addition, ~~terms~~later ~~and~~discovery ~~provisions~~ of ~~our~~previously ~~common~~unknown ~~stock~~adverse ~~and~~events ~~each~~or other ~~class~~problems ofwith our ~~securities~~tablet ~~which~~vaccine ~~qualifies~~candidates, manufacturers or ~~limits~~manufacturing ~~our~~processes, ~~common~~or ~~stock~~failure ~~are described~~to ~~under~~comply ~~the~~with ~~caption~~regulatory ~~"Description~~requirements, ofmay ~~Capital~~yield ~~Stock"~~various inresults, ~~this prospectus.~~ including:

~~Pre-Funded~~● ~~Warrants~~ restrictions on manufacturing such tablet vaccine candidate;

~~The~~● ~~following~~restrictions ~~summary~~on ~~of certain terms and provisions of pre-funded warrants that are being offered hereby is not complete and is subject to, and qualified in its entirety by,~~ the ~~provisions~~labeling ofor ~~the~~marketing ~~pre-funded warrant, the form~~ of ~~which is filed as an exhibit to the registration statement of which this prospectus forms~~ a ~~part.~~tablet ~~Prospective~~vaccine ~~investors should carefully review the terms and provisions of the form of pre-funded warrant for a complete description of the terms and conditions of the pre-funded warrants.~~candidate;

~~Duration~~● ~~and~~restrictions ~~Exercise~~on ~~Price. Each~~tablet ~~pre-funded~~vaccine ~~warrant~~distribution offered hereby will have an initial exercise price per share equal to $0.10. The pre-funded warrants will be immediately exercisable and may be exercised at any time until the pre-funded warrants are exercised in full. The exercise price and number of shares of common stock issuable upon exercise is subject to appropriate adjustment in the event of stock dividends, stock splits, reorganizations or similar events affecting our common stock and the exercise price. The pre-funded warrants will be issued separately from the accompanying common warrants, and may be transferred separately immediately thereafter. use;

~~Exercisability. The~~● ~~pre-funded~~requirements ~~warrants will be exercisable, at the option of each holder, in whole or in part, by delivering~~ to usconduct a duly executed exercise notice accompanied by payment in full for the number of shares of our common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below). A holder (together with its affiliates) may not exercise any portion of the prepost-~~funded~~marketing ~~warrant~~studies to the extent that the holder would own more than 4.99% of the outstanding common stock immediately after exercise, except that upon at least 61 days' prior notice from the holder to us, the holder may increase the amount of ownership of outstanding stock after exercising the holder's pre-funded warrants up to 9.99% of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. Purchasers of pre-funded warrants in this offering may also elect prior to the issuance of the pre-funded warrants to have the initial exercise limitation set at 9.99% of our outstanding common stock. No fractional shares of common stock will be issued in connection with the exercise of a pre-funded warrant. In lieu of fractional shares, we will either pay the holder an amount in cash equal to the fractional amount multiplied by the exercise price or ~~round~~clinical ~~up to the next whole share.~~ trials;

~~Cashless~~● ~~Exercise. If,~~warning at the time a holder exercises its pre-funded warrants, a registration statement registering the issuance of the shares of common stock underlying the pre-funded warrants under the Securities Act is not then effective or available, then in lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price, the holder may elect instead to receive upon such exercise (either in whole or in part) the net letters;

●	withdrawal of the tablet vaccine candidate from the market;

●	refusal to approve pending applications or supplements to approved applications that we submit;

●	recall of such tablet vaccine candidate;

●	fines, restitution or disgorgement of profits or revenues;

●	suspension or withdrawal of marketing approvals;

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~~number of~~● ~~shares~~refusal ~~of common stock determined according~~ to apermit ~~formula~~the ~~set~~import ~~forth~~or inexport ~~the~~of ~~pre-funded~~such ~~warrants.~~tablet vaccine candidate;

~~Transferability. Subject~~● totablet ~~applicable~~vaccine ~~laws,~~candidate aseizure; ~~pre-funded warrant may be transferred at the option of the holder upon surrender of the pre-funded warrant to us together with the appropriate instruments of transfer.~~ or

~~Exchange~~● ~~Listing. There~~injunctions ~~is no trading market available for the pre-funded warrants on any securities exchange~~ or ~~nationally recognized trading system. We do not intend to list~~ the ~~pre-funded~~imposition ~~warrants~~of oncivil ~~any securities exchange~~ or ~~nationally~~criminal ~~recognized trading system~~penalties.

~~Right~~The asFDA’s apolicies ~~Stockholder. Except~~may aschange, ~~otherwise~~and ~~provided~~additional ingovernment ~~the~~regulations ~~pre-funded~~may ~~warrants~~be orenacted, bythat ~~virtue~~could ofprevent, ~~such~~limit ~~holder's~~or ~~ownership~~delay regulatory approval of ~~shares~~any of our ~~common stock,~~tablet ~~the~~vaccine ~~holders~~candidates. ofIf ~~the~~we ~~pre-funded~~are ~~warrants~~slow door ~~not~~unable ~~have~~to ~~the~~adapt ~~rights~~to orchanges ~~privileges~~in ofexisting ~~holders~~requirements or the adoption of ~~our~~new ~~common~~requirements ~~stock~~or policies, ~~including~~or ~~any~~if ~~voting~~we ~~rights~~are not able to maintain regulatory compliance, ~~until~~we ~~they~~may ~~exercise~~lose ~~their~~any ~~pre-funded~~marketing ~~warrants.~~approval that we may have obtained.

~~Fundamental~~Even ~~Transaction. In~~if ~~the event of a fundamental transaction, as described in the pre-funded warrants and generally including any reorganization, recapitalization or reclassification of~~ our ~~common~~tablet ~~stock,~~vaccine ~~the~~candidates ~~sale,~~receive ~~transfer~~marketing ~~or other disposition of all or substantially all of our properties or assets~~approval, ~~our~~they ~~consolidation~~may orfail ~~merger with~~to orachieve ~~into~~market ~~another~~acceptance ~~person,~~by ~~the acquisition of more than 50% of our outstanding common stock~~physicians, ~~or any person or group becoming the beneficial owner of 50% of the voting power represented by our outstanding common stock~~patients, ~~the holders of the pre~~third-~~funded~~party ~~warrants~~payors ~~will be entitled to receive upon exercise of the pre-funded warrants the kind and amount of securities, cash~~ or ~~other~~others ~~property~~in ~~that~~ the ~~holders~~ ~~would~~medical ~~have~~community ~~received~~necessary ~~had~~for ~~they~~commercial ~~exercised the pre-funded warrants immediately prior to such fundamental transaction~~success.

~~Common~~If ~~Warrants~~ our tablet vaccine candidates, including our vaccine for coronavirus and norovirus, receive marketing approval, they may nonetheless fail to gain sufficient market acceptance by physicians, patients, third-party payors and others in the medical community. If they do not achieve an adequate level of acceptance, we may not generate significant revenues and become profitable. The degree of market acceptance, if approved for commercial sale, will depend on a number of factors, including but not limited to:

~~The~~● ~~following~~the ~~summary~~efficacy ~~of certain terms~~ and ~~provisions~~potential ofadvantages ~~common~~compared ~~warrants that are being offered hereby is not complete and is subject~~ to, ~~and~~alternative qualified in its entirety by, the provisions of the common warrants, the form of which is filed as an exhibit to the registration statement of which this prospectus forms a part. Prospective investors should carefully review the terms and provisions of the form of common warrant for a complete description of the terms and conditions of the common warrants.treatments;

~~Duration~~● ~~and~~effectiveness Exercise Price. Each common warrant offered hereby will have an initial exercise price per share equal to $ . The common warrants will be immediately exercisable and will expire on the fifth anniversary of ~~the~~sales ~~original issuance date. The exercise price~~ and ~~number~~marketing of shares of common stock issuable upon exercise is subject to appropriate adjustment in the event of stock dividends, stock splits, reorganizations or similar events affecting our common stock and the exercise price. The common warrants will be issued separately from the common stock, and may be transferred separately immediately thereafter. A common warrant to purchase one share of our common stock will be issued for every one share of common stock or pre-funded warrant purchased in this offering. efforts;

~~Exercisability. The~~● ~~common warrants will be exercisable, at~~ the ~~option~~cost of ~~each~~treatment ~~holder,~~ in ~~whole~~relation ~~or in part, by delivering~~ to usalternative a duly executed exercise notice accompanied by payment in full for the number of shares of our common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below). A holder (together with its affiliates) may not exercise any portion of the common warrant to the extent that the holder would own more than 4.99% of the outstanding common stock immediately after exercise, except that upon at least 61 days' prior notice from the holder to us, the holder may increase the amount of ownership of outstanding stock after exercising the holder's common warrants up to 9.99% of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the common warrants. Purchasers in this offering may also elect prior to the issuance of the treatments;

●	our ability to offer our tablet vaccine candidates for sale at competitive prices;

●	the convenience and ease of administration compared to alternative treatments;

●	the willingness of the target patient population to try new therapies and of physicians to prescribe these therapies;

●	the willingness of the medical community to offer customers our tablet vaccine candidate option in addition to, or in the place of, injectable vaccines;

●	the strength of marketing and distribution support;

●	the availability of third-party coverage and adequate reimbursement;

●	the prevalence and severity of any side effects; and

●	any restrictions on the use of our tablet vaccine together with other medications.

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~~common warrants~~Because towe ~~have~~expect ~~the~~sales ~~initial exercise limitation set at 9.99%~~ of our ~~outstanding~~tablet ~~common~~vaccine ~~stock.~~candidate Nofor ~~fractional~~coronavirus ~~shares~~and/or ofnorovirus, ~~common~~if ~~stock~~approved, ~~will~~to begenerate ~~issued~~substantially inall ~~connection with the exercise~~ of aour ~~common warrant.~~revenues Infor ~~lieu~~the offoreseeable ~~fractional shares~~future, wethe ~~will~~failure ~~either~~of ~~pay~~these ~~the~~tablet ~~holder~~vaccines anto ~~amount~~achieve inmarket ~~cash~~acceptance ~~equal~~would toharm ~~the~~our ~~fractional~~business ~~amount~~and ~~multiplied~~could byrequire ~~the~~us ~~exercise~~to ~~price~~seek oradditional ~~round~~financing upsooner tothan ~~the~~we ~~next~~would ~~whole~~otherwise ~~share~~plan.

~~Cashless Exercise.~~ If, atwe ~~the~~fail ~~time~~to acomply ~~holder~~with ~~exercises~~state ~~its~~and ~~common~~federal ~~warrants,~~healthcare aregulatory ~~registration~~laws, ~~statement~~we ~~registering~~could ~~the~~face ~~issuance~~substantial ofpenalties, ~~the shares~~damages, offines, ~~common stock~~disgorgement, ~~underlying~~exclusion ~~the common warrants under the Securities Act is not then effective or available and an exemption~~ from ~~registration~~participation ~~under~~in ~~the~~governmental ~~Securities~~healthcare ~~Act is not available for the issuance of such shares~~programs, ~~then~~and ~~in lieu of making~~ the ~~cash~~curtailment ~~payment otherwise contemplated to be made to us upon such exercise in payment~~ of ~~the~~our ~~aggregate exercise price~~operations, ~~the~~any ~~holder may elect instead to receive upon such exercise (either in whole or in part) the net number~~ of ~~shares~~which ofcould ~~common~~harm ~~stock~~our ~~determined according to a formula set forth in the common warrants~~business.

~~Transferability. Subject~~Although towe ~~applicable~~do ~~laws,~~not aprovide ~~common~~healthcare ~~warrant~~services ~~may~~or besubmit ~~transferred~~claims atfor ~~the~~third-party ~~option~~reimbursement, ofwe ~~the~~are ~~holder~~subject ~~upon~~to ~~surrender~~healthcare offraud ~~the common~~and ~~warrant~~abuse ~~to us~~regulation ~~together~~and ~~with~~enforcement ~~the~~by ~~appropriate~~federal ~~instruments~~and ofstate ~~transfer~~governments, which could significantly impact our business. The laws that may affect our ability to operate include, but are not limited to:

~~Exchange~~● ~~Listing. There~~the isfederal noAnti-Kickback ~~trading~~Statute, ~~market~~which ~~available~~prohibits, ~~for~~among ~~the~~other ~~common~~things, ~~warrants~~persons onand ~~any~~entities ~~securities~~from ~~exchange~~knowingly and willfully soliciting, receiving, offering, or ~~nationally~~paying ~~recognized trading~~remuneration, ~~system.~~directly ~~We do~~or ~~not~~indirectly, ~~intend~~in cash or in kind, in exchange for or to ~~list~~induce either the ~~common~~referral ~~warrants~~of onan individual for, or the purchase, lease, order or recommendation of, any ~~securities~~good, ~~exchange~~facility, item or ~~nationally~~service ~~recognized~~for ~~trading~~which ~~system~~payment may be made, in whole or in part, under federal healthcare programs such as Medicare and Medicaid. A person or entity does not need to have actual knowledge of this statute or specific intent to violate it;

~~Right~~● asthe acivil ~~Stockholder. Except~~False asClaims ~~otherwise~~Act ~~provided~~(“FCA”), inwhich ~~the~~prohibits, ~~common~~among ~~warrants~~other things, individuals or byentities ~~virtue~~from ofknowingly ~~such~~presenting, ~~holder's~~or ~~ownership~~causing ofto ~~shares~~be ofpresented, ~~our common~~claims ~~stock~~for payment from Medicare, ~~the~~ ~~holders~~Medicaid ofor ~~the~~other ~~common~~third-party ~~warrants~~payors dothat ~~not~~are ~~have~~false or fraudulent; knowingly making, using, or causing to be made or used, a false record or statement to get a false or fraudulent claim paid or approved by the ~~rights~~government; or ~~privileges~~knowingly ofmaking, ~~holders~~using, ofor ~~our~~causing ~~common~~to ~~stock~~be made or used, ~~including~~a ~~any~~false ~~voting~~record ~~rights~~or statement to avoid, ~~until~~decrease ~~they~~or ~~exercise~~conceal ~~their~~an ~~common~~obligation ~~warrants.~~to pay money to the federal government;

~~Fundamental~~● ~~Transaction. In~~ the ~~event~~criminal ~~of a fundamental transaction~~FCA, aswhich ~~described~~imposes incriminal ~~the~~fines ~~common warrants and generally including any reorganization, recapitalization~~ or ~~reclassification~~imprisonment ofagainst ~~our~~individuals ~~common stock, the sale, transfer~~ or ~~other~~entities ~~disposition~~who ofmake ~~all~~ or ~~substantially~~present all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding common stock, or any person or group becoming the beneficial owner of 50% of the voting power represented by our outstanding common stock, the holders of the common warrants will be entitled to receive upon exercise of the common warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the common warrants immediately prior to such fundamental transaction. Notwithstanding the foregoing, in the event of a ~~fundamental~~claim ~~transaction, the holders will have the option, which may be exercised within 30 days after the consummation of the fundamental transaction,~~ to ~~require us or our successor entity to purchase~~ the ~~common~~government ~~warrants~~knowing from the holder by paying to the holder an amount of cash equal to the Black Scholes value of the remaining unexercised portion of the common warrant on the date of the consummation of the fundamental transaction. However, if the fundamental transaction is not within our control, including not approved by our board of directors, the holder will only be entitled to receive from us or our successor entity, as of the date of consummation of such ~~fundamental transaction,~~claim ~~the same type or form of consideration (and in the same proportion), at the Black Scholes value of the unexercised portion of the common warrant, that is being offered and paid~~ to ~~the holders of common stock in connection with the fundamental transaction, whether that consideration~~ be ~~in the form of cash~~false, ~~stock~~fictitious or ~~any combination thereof, or whether the holders of common stock are given the choice to receive from among alternative forms of consideration in connection with the fundamental transaction.~~ fraudulent;

●	the federal Health Insurance Portability and Accountability Act of 1996 (“HIPAA”), which created federal criminal laws that prohibit executing a scheme to defraud any healthcare benefit program or making false statements relating to healthcare matters;

●

the federal civil monetary penalties statute, which prohibits, among other things, the offering or giving of remuneration to a Medicare or Medicaid beneficiary that the person knows or should know is likely to influence the beneficiary’s selection of a particular supplier of items or services reimbursable by a federal or state governmental program;

●

the federal physician sunshine requirements under the Affordable Care Act, which require certain manufacturers of drugs, devices, biologics, and medical supplies to report annually to the U.S. Department of Health and Human Services information related to payments and other transfers of value to physicians, other healthcare providers, and teaching hospitals, and ownership and investment interests held by physicians and other healthcare providers and their immediate family members; and

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● state ~~UNDERWRITING~~ law equivalents of each of the above federal laws, such as anti-kickback and false claims laws that may apply to items or services reimbursed by any third-party payor, including commercial insurers; state laws that require pharmaceutical companies to comply with the device industry’s voluntary compliance guidelines and the relevant compliance guidance promulgated by the federal government, or otherwise restrict payments that may be made to healthcare providers and other potential referral sources; and state laws that require device manufacturers to report information related to payments and other transfers of value to physicians and other healthcare providers or marketing expenditures.

WeFurther, ~~have~~the ~~entered~~Affordable ~~into~~Care anAct, ~~underwriting~~among ~~agreement~~other ~~with~~things, ~~H.C.~~amended ~~Wainwright & Co., LLC~~the asintent requirements of the ~~sole~~federal ~~book~~Anti-~~running~~Kickback ~~manager~~Statute ofand ~~this offering~~certain criminal statutes governing healthcare fraud. ~~Subject~~A toperson ~~the~~or ~~terms~~entity ~~and~~can ~~conditions~~now be found guilty of violating the ~~underwriting~~statute ~~agreement,~~without weactual ~~have~~knowledge ~~agreed~~of tothe ~~sell~~statute or specific intent to ~~the~~violate ~~underwriters~~it. In addition, ~~and~~the Affordable Care Act provided that the ~~underwriters~~government ~~have~~may ~~agreed~~assert tothat ~~purchase~~a claim including items or services resulting from ~~us,~~a ~~shares~~violation of ~~our~~the ~~common stock~~federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the FCA. Moreover, while we do not, and ~~pre-funded~~will ~~warrants~~not, submit claims and ~~accompanying~~our ~~common~~customers ~~warrants~~will make the ultimate decision on how to ~~purchase~~submit ~~shares~~claims, ofwe may provide reimbursement guidance to our ~~common~~customers ~~stock~~from time to time. ~~Our~~If ~~common~~a ~~stock~~government isauthority ~~listed~~were onto ~~the~~conclude ~~Nasdaq~~that ~~Capital~~we ~~Market~~provided ~~under~~improper advice to our customers or encouraged the ~~symbol~~submission ~~"VXRT~~of false claims for reimbursement, we could face action against us by government authorities." Any violations of these laws, or any action against us for violation of these laws, even if we successfully defend against it, could result in a material adverse effect on our reputation, business, results of operations and financial condition.

~~Pursuant to~~We ~~the~~have ~~terms~~entered into consulting and ~~subject~~scientific toadvisory ~~the~~board ~~conditions~~arrangements ~~contained~~with inphysicians and other healthcare providers. Compensation for some of these arrangements includes the ~~underwriting~~provision ~~agreement,~~of stock options. While we have ~~agreed~~worked to ~~sell~~structure our arrangements to ~~the~~comply ~~underwriters~~with ~~named~~applicable ~~below~~laws, ~~and~~because of the ~~underwriters~~complex ~~have~~and ~~agreed~~far-reaching ~~to purchase~~nature ~~from~~of usthese laws, ~~the~~regulatory ~~respective~~agencies ~~number~~may ofview ~~shares~~these oftransactions ~~common~~as ~~stock~~prohibited arrangements that must be restructured, ~~pre-funded~~or ~~warrants~~discontinued, ~~and~~or ~~common~~for ~~warrants~~which we could be subject to ~~purchase~~other ~~common~~significant ~~stock~~penalties. ~~set~~We ~~forth~~could ~~opposite~~be ~~their~~adversely ~~name~~affected ~~below:~~if regulatory agencies interpret our financial relationships with providers who influence the ordering of and use our products to be in violation of applicable laws.

Underwriter		Number of Shares of Common Stock			Number of Pre-Funded Warrants			Number of Common Warrants
H.C. Wainwright & Co., LLC
Brookline Capital Markets, a division of Arcadia Securities, LLC

Total

The scope and enforcement of each of these laws is uncertain and subject to rapid change in the current environment of healthcare reform, especially in light of the lack of applicable precedent and regulations. Federal and state enforcement bodies have recently increased their scrutiny of interactions between healthcare companies and healthcare providers, which has led to a number of investigations, prosecutions, convictions and settlements in the healthcare industry.

~~The underwriting~~Responding ~~agreement provides that the obligation of the underwriters~~ to ~~purchase~~investigations ~~the~~can ~~shares~~be oftime- ~~common stock~~ and~~/or~~ ~~pre~~resource-~~funded~~consuming ~~warrants~~ and ~~common~~can ~~warrants~~divert tomanagement’s ~~purchase~~attention ~~shares~~from ~~of common~~the ~~stock~~business. ~~offered~~Additionally, byas ~~this~~a ~~prospectus~~result isof ~~subject~~these toinvestigations, ~~certain~~healthcare ~~conditions.~~providers ~~The~~and ~~underwriters~~entities ~~are~~may ~~obligated~~have to ~~purchase~~agree ~~all~~to ofadditional ~~the~~onerous ~~shares~~compliance ~~of common stock~~ and~~/or~~ ~~pre-funded~~reporting ~~warrants~~requirements ~~and~~as ~~common~~part ~~warrants to purchase shares~~ of ~~our~~a ~~common~~consent ~~stock~~decree ~~offered~~or ~~hereby~~corporate ifintegrity ~~any~~agreement. ofAny ~~the~~such ~~securities~~investigation ~~are~~or ~~purchased,~~settlement ~~other~~could ~~than~~increase ~~those~~our ~~shares~~costs ~~covered~~or byotherwise ~~the~~have ~~option~~an toadverse ~~purchase~~effect ~~additional~~on ~~shares~~our ~~and/or common warrants described below~~business.

~~Option~~Product liability lawsuits against us could cause us to ~~Purchase~~incur ~~Additional~~substantial ~~Securities~~ liabilities and could limit the commercialization of any tablet vaccine candidates we may develop.

We ~~have~~face ~~granted~~an ~~the~~inherent ~~underwriters~~risk anof ~~option~~product liability exposure related to ~~purchase~~the ~~additional~~testing ~~securities.~~of ~~This~~our ~~option,~~tablet ~~which~~vaccine iscandidates ~~exercisable~~in ~~for~~human upclinical totrials ~~30 days~~and ~~after the~~will ~~date~~face ofan ~~this~~even ~~prospectus,~~greater ~~permits~~risk ~~the~~if ~~underwriters~~we tocommercially ~~purchase~~sell upany ~~to shares~~products ofthat ~~common~~we ~~stock~~may atdevelop aafter ~~price of~~approval. ~~$ per~~For ~~share~~instance, ~~and/or~~since ~~common~~our ~~warrants~~norovirus ~~exercisable~~tablet ~~for~~challenge upstudy ~~to shares~~is ofbeing ~~common~~conducted ~~stock~~in athealthy ahuman ~~price~~volunteers, ~~of $ per~~any ~~common~~adverse ~~warrant,~~reactions ~~less~~could ~~underwriting~~result ~~discounts~~in claims from these injuries and ~~commissions~~we could incur substantial liabilities. Regardless of merit or eventual outcome, liability claims may result in:

~~Discounts,~~● ~~Commissions~~decreased ~~and~~demand ~~Expenses~~ for any tablet vaccine candidates that it may develop;

~~The~~● ~~underwriters~~injury ~~propose~~ to ~~offer the shares of common stock and pre-funded warrants and accompanying common warrants to purchase shares of~~ our ~~common~~ ~~stock~~reputation ~~pursuant to the underwriting agreement to the public at the combined public offering price set forth on the cover page of this prospectus~~ and tosignificant ~~certain~~negative ~~dealers~~media at that price less a concession not in excess of $ per share based on the combined public offering price per share and accompanying common warrant set forth on the cover page of this prospectus. After this offering, the public offering price and concession may be changed by the underwriters. No such change shall change the amount of proceeds to be received by us as set forth on the cover page of this prospectus. attention;

In connection with the sale of the common stock and pre-funded warrants and accompanying common warrants to purchase shares of our common stock to be purchased by the underwriters, the underwriters will be deemed to have received compensation in the form of underwriting discounts and commissions. The underwriting discounts and commissions will be 7% of the gross proceeds of this

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~~offering, or~~● ~~$ per~~withdrawal ~~share~~ of ~~common~~clinical ~~stock~~trial ~~and accompanying common warrant or per pre-funded warrant and accompanying common warrant.~~ participants;

~~The following~~● ~~table~~significant ~~shows~~costs ~~underwriting discounts and commissions payable~~ to ~~the~~defend ~~underwriters~~any byrelated ~~us in connection with this offering:~~ litigation;

				Total
		Per Pre-Funded Warrant	Per Common Warrant
	Per Share			No Exercise	Full Exercise
Public offering price	$	$	$	$	$
Underwriting discounts and commissions payable by us	$	$	$	$	$

●	substantial monetary awards to trial subjects or patients;

~~We have~~● ~~also~~loss ~~agreed to reimburse H.C. Wainwright & Co., LLC for reasonable out-~~of~~-pocket~~ ~~expenses,~~revenue; ~~including legal fees~~ and ~~expenses, of up to $75,000. We estimate the total expenses payable by us for this offering will be approximately $400,000, which amount excludes underwriting discounts and commissions.~~

~~Representative~~● ~~Warrants~~ the inability to commercialize any products we may develop.

InAlthough ~~addition,~~ we ~~have~~maintain ~~agreed~~product toliability ~~issue~~insurance tocoverage the underwriters or their designees warrants to purchase up to shares of common stock (which represents 7% of the aggregate number of shares of common stock sold in ~~this offering (including~~ the ~~number~~amount of ~~shares~~up ~~of common stock issuable upon exercise of the pre-funded warrants and the underwriters' option~~ to ~~purchase additional shares of common stock if exercised) at an exercise price of~~ $ ~~per~~10 ~~share~~million ~~of common stock (representing 125% of the combined public offering price~~ per ~~share~~claim ofand ~~common stock to be sold~~ in ~~this offering). The warrants will each have a term of five years from~~ the ~~effective date of the registration statement of which this prospectus forms a part. Pursuant to the Financial Industry Regulatory Authority~~aggregate, ~~Inc.,~~ orit ~~FINRA, Rule 5110(g), the warrants and any shares of common stock issued upon exercise of the warrants~~ may not be ~~sold,~~adequate ~~transferred,~~to ~~assigned,~~cover ~~pledged~~all orliabilities ~~hypothecated,~~that orwe bemay ~~the~~incur. ~~subject of any hedging~~Additionally, ~~short~~seasonal ~~sale,~~influenza ~~derivative,~~is ~~put~~a orcovered ~~call~~vaccine ~~transaction that would result in the effective economic disposition~~ of the ~~securities~~National byVaccine ~~any~~Injury ~~person~~Compensation ~~for a period of 180 days immediately following the date of effectiveness or commencement of sales of this offering~~Program, ~~except~~and ~~the transfer of any security: (i) by operation of law or by reason of~~ our ~~reorganization;~~participation ~~(ii) to~~in ~~any~~that ~~FINRA~~program ~~member~~may ~~firm~~require ~~participating~~time ~~in the offering~~ and ~~the~~resources ~~officers~~that ~~or partners~~impede ~~thereof~~product uptake, if ~~all~~approved. ~~securities~~We soanticipate ~~transferred~~that ~~remain~~we ~~subject~~will need to ~~the~~increase ~~lock-up~~our ~~restriction~~insurance ~~set~~coverage ~~forth~~as ~~above~~we ~~for~~continue ~~the~~clinical ~~remainder~~trials ofand ~~the time period; (iii)~~ if ~~the~~we ~~aggregate~~successfully ~~amount~~commercialize ofany ~~our securities~~products. ~~held~~Insurance bycoverage ~~the~~is ~~underwriters~~increasingly orexpensive. ~~related~~We ~~persons~~may do not ~~exceed~~be 1%able ofto ~~the~~maintain ~~securities~~insurance ~~being~~coverage ~~offered;~~at ~~(iv) that is beneficially owned on~~ a ~~pro-rata~~reasonable ~~basis~~cost ~~by all equity owners of an investment fund, provided that no participating member manages~~ or ~~otherwise directs investments by the fund and the participating members~~ in ~~the~~an ~~aggregate~~amount doadequate ~~not~~to ~~own~~satisfy ~~more than 10% of the equity in the fund; or (v) the exercise or conversion of~~ any ~~security,~~liability ifthat ~~all~~may ~~securities remain subject to the lock-up restriction set forth above for the remainder of the time period~~arise.

~~Right~~If ofa ~~First~~product ~~Refusal~~ liability claim is successfully brought against us for uninsured liabilities, or such claim exceeds our insurance coverage, we could be forced to pay substantial damage awards that could materially harm our business.

The use of any of our existing or future product candidates in clinical trials and the sale of any approved pharmaceutical products may expose us to significant product liability claims. We currently have ~~granted~~product Hliability insurance coverage for our ongoing clinical trials in the amount of up to $10 million.C Further, we also require clinical research and manufacturing organizations that assist us in the conduct of our trials or manufacture materials used in these trials to carry product liability insurance against such claims. ~~Wainwright & Co~~This insurance coverage may not protect us against any or all of the product liability claims that may be brought against us in the future. We may not be able to acquire or maintain adequate product liability insurance coverage at a commercially reasonable cost or in sufficient amounts or scope to protect ourselves against potential losses. In the event a product liability claim is brought against us, ~~LLC~~ ~~certain~~we ~~rights~~may ofbe ~~first~~required ~~refusal~~to pay legal and other expenses to ~~act~~defend the claim, as anwell ~~underwriter~~as uncovered damage awards resulting from a claim brought successfully against us. In the event any of our product candidates are approved for sale by the FDA or ~~placement~~similar ~~agent until~~regulatory ~~April~~authorities ~~2020~~in other countries and commercialized, we may need to substantially increase the amount of our product liability coverage. Defending any product liability claim or claims could require us to expend significant financial and managerial resources, which could have an adverse effect on our business.

~~Indemnification~~ If we are unable to establish sales, marketing and distribution capabilities either on our own or in collaboration with third parties, we may not be successful in commercializing our tablet vaccine candidates, if approved.

~~Pursuant~~We todo not have any infrastructure for the ~~underwriting~~sales, ~~agreement~~marketing or distribution of our tablet vaccine candidates, weand ~~have~~the ~~agreed~~cost toof ~~indemnify~~establishing and maintaining such an organization may exceed the ~~underwriters~~cost-effectiveness ~~against~~of ~~certain~~doing ~~liabilities~~so. In order to market any tablet vaccine candidates that may be approved, ~~including~~we ~~liabilities~~must ~~under the~~build ~~Securities~~our ~~Act~~sales, distribution, marketing, managerial and other non-technical capabilities or make arrangements with third parties to ~~contribute~~perform these services. To achieve commercial success for any tablet vaccine candidates for which we have obtained marketing approval, we will need a sales and marketing organization. While we expect to ~~payments~~partner ~~that~~our ~~the~~tablet ~~underwriter~~vaccine orfor ~~such~~seasonal influenza, we may build a focused sales, distribution and marketing infrastructure to market our other ~~indemnified~~tablet ~~parties~~vaccine ~~may~~candidates bein ~~required~~the U.S., if approved. There are significant expenses and risks involved with establishing our own sales, marketing and distribution capabilities, including our ability to ~~make~~hire, retain and appropriately incentivize qualified individuals, generate sufficient sales leads, provide adequate training to sales and marketing personnel, and effectively manage a geographically dispersed sales and marketing team. Any failure or delay in ~~respect~~the development of ~~those~~our ~~liabilities.~~internal sales, marketing and distribution capabilities could delay any tablet vaccine candidate launch, which would adversely impact commercialization.

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~~Determination~~Factors ofthat ~~Offering~~may ~~Price~~ inhibit our efforts to commercialize our tablet vaccine candidates on our own include:

~~The~~● ~~actual offering price of the securities we are offering will be negotiated between us and the underwriters based on the trading of~~ our ~~shares~~ ofinability ~~common stock prior~~ to ~~the offering~~recruit, ~~among~~train ~~other things,~~ and ~~may~~retain beadequate atnumbers aof ~~discount~~effective tosales ~~the~~and ~~current~~marketing ~~market price.~~ personnel;

~~Lock-Up~~● ~~Agreements~~ the inability of sales personnel to obtain access to physicians or attain adequate numbers of physicians to administer our tablet vaccines; and

We● ~~have~~unforeseen ~~agreed~~costs ~~not~~and toexpenses ~~(i) offer,~~associated pledge, issue, sell, contract to sell, purchase, contract to purchase, lend or otherwise transfer or dispose of, directly or indirectly, any shares of our common stock or any securities convertible into or exercisable or exchangeable for our common stock; (ii) enter into any swap or other arrangement that transfers, in whole or in part, any of the economic consequences of ownership of shares of common stock; or (iii) file any registration statement with ~~the~~creating ~~SEC~~an ~~relating~~independent tosales the offering of any shares of our common stock or any securities convertible into or exercisable or exchangeable for shares of our common stock, without the prior written consent of H.C. Wainwright & Co., LLC for a period of 90 days following the date of this prospectus. This consent may be given at any time without public notice. These restrictions on future issuances are subject to exceptions, including for (i) the issuance of shares of our common stock in this offering and ~~shares~~marketing of our common stock underlying the pre-funded warrants, common warrants and representative warrants, (ii) the issuance of shares of our common stock upon the exercise of outstanding options or pursuant to certain other rights, (iii) the issuance of shares of our common stock or options to acquire shares of our common stock pursuant to our equity incentive plans, and (iv) the filing of one or more registration statements on Form S-8 with respect to shares of our common stock underlying our equity incentive plans from time to timeorganization.

~~In addition,~~We ~~subject~~intend to ~~certain~~pursue ~~limited~~collaborative ~~circumstances,~~arrangements ~~each~~regarding ofthe ~~our~~sale ~~directors~~ and ~~executive~~marketing ~~officers,~~of ~~and~~ our ~~principal~~tablet ~~stockholder,~~vaccine ~~has entered into a lock-up agreement with the underwriters. Under the lock-up agreements~~candidates, ~~the~~if ~~directors~~approved, ~~executive~~for ~~officers~~certain ~~and~~international ~~this~~markets; ~~stockholder~~however, we may not, ~~directly~~be orable ~~indirectly, sell, offer~~ to ~~sell,~~establish ~~contract to sell,~~ or ~~grant~~maintain ~~any~~such ~~option~~collaborative ~~for~~arrangements ~~the sale (including any short sale)~~and, ~~grant~~if ~~any~~able ~~security~~to ~~interest~~do inso, ~~pledge,~~our ~~hypothecate,~~collaborators ~~hedge,~~may ~~establish~~not anhave ~~open~~effective ~~"put~~sales. ~~equivalent~~To ~~position" (within~~ the ~~meaning~~extent ofthat ~~Rule 16a-1(h)~~we ~~under~~depend ~~the Securities~~on ~~Exchange~~third ~~Act~~parties offor ~~1934,~~marketing asand ~~amended~~distribution, ~~or the Exchange Act), or otherwise dispose of, or enter into~~ any ~~transaction~~revenues ~~which~~we isreceive ~~designed~~will todepend orupon ~~could be expected to result in~~ the ~~disposition~~efforts of, ~~any shares~~such ofthird ~~our common stock or securities convertible into or exchangeable for shares of our common stock~~parties, orand ~~publicly~~we ~~announce~~cannot ~~any~~assure ~~intention~~you tothat dosuch ~~any~~efforts ofwill ~~the foregoing, without the prior written consent of H.C. Wainwright & Co., LLC, for a period of 90 days from the date of this prospectus. This consent may~~ be ~~given at any time without public notice~~successful.

~~Price~~If ~~Stabilization~~we are unable to build our own sales force in the U.S. or negotiate a collaborative relationship for the commercialization of our tablet vaccine candidates outside the U.S., ~~Short~~we ~~Positions~~may be forced to delay the potential commercialization or reduce the scope of our sales and ~~Penalty~~marketing ~~Bids~~ activities. We could have to enter into arrangements with third parties at an earlier stage than we would otherwise choose and we may be required to relinquish rights to our intellectual property or otherwise agree to terms unfavorable to us, any of which may have an adverse effect on our business, operating results and prospects.

~~The~~We ~~underwriters~~ may ~~engage~~be incompeting ~~syndicate~~with ~~covering~~many ~~transactions,~~companies ~~stabilizing~~that ~~transactions~~currently have extensive and ~~penalty~~well-funded ~~bids~~marketing orand ~~purchases~~sales ~~for~~operations. Without an internal team or the ~~purpose~~support of ~~pegging~~ a third party to perform marketing and sales functions, ~~fixing~~we ormay ~~maintaining~~be ~~the~~unable ~~price~~to ofcompete ~~our~~successfully ~~shares~~against ofthese ~~common~~more ~~stock:~~established companies.

If we obtain approval to commercialize any tablet vaccine candidates outside of the United States, a variety of risks associated with international operations could harm our business.

If our tablet vaccine candidates are approved for commercialization, we intend to enter into agreements with third parties to market them in certain jurisdictions outside the U.S. We expect that we will be subject to additional risks related to international operations or entering into international business relationships, including:

●	different regulatory requirements for drug approvals and rules governing drug commercialization in foreign countries;

●	reduced protection for intellectual property rights;

●	unexpected changes in tariffs, trade barriers and regulatory requirements;

●	economic weakness, including inflation, or political instability in particular foreign economies and markets;

●	compliance with tax, employment, immigration and labor laws for employees living or traveling abroad;

●	foreign reimbursement, pricing and insurance regimes;

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~~These syndicate~~● ~~covering~~foreign transactions, stabilizing transactions and penalty bids may have the effect of raising or maintaining the market prices of our securities or preventing or retarding a decline in the market prices of our securities. As a result, the price of our shares of common stock may be higher than the price that might otherwise exist in the open market. Neither we nor the underwriter make any representation or prediction as to the effect that the transactions described above may have on the price of our shares of common stock. These transactions may be effected on the Nasdaq Capital Market, in the over-the-counter market or on any other trading market and, if commenced, may be discontinued at any time. taxes;

~~In connection~~● ~~with~~foreign ~~this~~currency ~~offering~~fluctuations, ~~the~~which ~~underwriters~~could ~~also~~result ~~may engage~~ in ~~passive~~increased ~~market~~operating ~~making~~expenses ~~transactions in our shares of common stock in accordance with Regulation M during a period before the commencement of offers or sales of our shares of common stock in this offering~~ and ~~extending~~reduced ~~through the completion of the distribution. In general~~revenues, aand ~~passive~~other ~~market~~obligations ~~maker~~incident ~~must display~~to ~~its~~doing ~~bid~~business ~~at a price not~~ in ~~excess~~another of the highest independent bid for that security. However, if all independent bids are lowered below the passive market maker's bid that bid must then be lowered when specific purchase limits are exceeded. Passive market making may stabilize the market price of the securities at a level above that which might otherwise prevail in the open market and, if commenced, may be discontinued at any time. country;

~~Neither we~~● ~~nor~~workforce ~~the~~uncertainty ~~underwriters~~in ~~make~~countries ~~any~~where ~~representation~~labor orunrest ~~prediction~~is asmore tocommon ~~the~~than ~~direction~~in ~~or magnitude of any effect that~~ the ~~transactions described above may have on the prices of our securities~~U. In addition, neither we nor the underwriters make any representation that the underwriters will engage in these transactions or that any transactions, once commenced, will not be discontinued without noticeS. ;

~~Other~~● ~~Relationships~~ potential noncompliance with the U.S. Foreign Corrupt Practices Act, the U.K. Bribery Act 2010 and similar anti-bribery and anticorruption laws in other jurisdictions;

~~From~~● ~~time~~tablet tovaccination ~~time,~~shortages ~~certain~~resulting offrom ~~the~~any ~~underwriters~~events ~~and~~affecting ~~their~~raw ~~affiliates~~material ~~have~~supply ~~provided,~~or ~~and~~manufacturing ~~may~~capabilities ~~provide~~abroad; ~~in the future, various advisory, investment~~ and ~~commercial banking and other services to us in the ordinary course of business, for which they have received and may continue to receive customary fees and commissions.~~

●	business interruptions resulting from geopolitical actions, including war and terrorism, or natural disasters including earthquakes, typhoons, floods and fires.

We have no prior experience in these areas. In addition, there are complex regulatory, tax, labor and other legal requirements imposed by both the European Union and many of the individual countries in Europe with which we will need to comply.

Government involvement may limit the commercial success of our tablet vaccine candidates.

Various government entities, including the U.S. government, are offering incentives, grants and contracts to encourage additional investment by commercial organizations into preventative and therapeutic agents against coronavirus and influenza, which may have the effect of increasing the number of competitors and/or providing advantages to known competitors. Accordingly, there can be no assurance that we will be able to successfully establish a competitive market share for our coronavirus or influenza vaccines.

In addition, current influenza vaccines are generally trivalent (containing three strains) or quadrivalent (containing four strains). If the FDA requires or recommends changes in influenza vaccines, for example, for a monovalent vaccine or for use of a strain that is not currently circulating in the human population, it is uncertain whether we will be able to produce or manufacture such a vaccine at commercially reasonable rates.

The seasonal nature of our target indications, in particular influenza, and competition from new products may cause unpredictable royalty revenues from Inavir and significant fluctuations in our operating results.

Influenza is seasonal in nature with sales of current vaccines occurring primarily in the first and fourth quarters of the calendar year. In addition, outbreaks of norovirus typically occur in the winter season. This seasonal concentration of product sales could cause quarter-to-quarter operating results to vary widely and can exaggerate the consequences of revenues of any manufacturing or supply delays, any sudden loss of inventory, any inability to satisfy product demand, the inability to estimate the effect of returns and rebates, normal or unusual fluctuations in customer buying patterns, or of any unsuccessful sales or marketing strategies during the sales seasons.

We earn royalty revenue from the net sales of Inavir, which is marketed by our licensee. Although the royalty rates paid to us by our licensees are fixed at a proportion of the licensee’s net sales of these products, our periodic and annual revenues from these royalties have historically been variable and subject to fluctuation based on the seasonal incidence and severity of influenza. It is the seasonality of influenza, which occurs mainly in the winter months, that causes our royalty revenue to be low in the second and third fiscal quarters, since our agreement with HealthCare Royalty Partners III, L.P. (see Note 6 to our Consolidated Financial Statements) has no impact on total revenue recognized, it only impacts our net cash flow in the quarter following revenue recognition. We cannot predict with any certainty what our royalty revenues are likely to be in any given year.

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In addition, ~~MATERIAL~~our Ulicensee may encounter competition from new products entering the market, including generic copies of Inavir, which could adversely affect our royalty income.S The last patent related to Inavir is set to expire in August 2036 in Japan, at which time royalty revenue will cease. ~~FEDERAL~~However, ~~INCOME~~the ~~TAX~~patent ~~CONSEQUENCES~~ covering the laninamivir octanoate compound expired in 2024, at which time generic competition may enter the market, potentially decreasing or eliminating the royalties received. On February 23, 2018, Osaka-based drug maker Shionogi & Co., Ltd. gained marketing approval for Xofluza, a new drug to treat influenza in Japan. The drug was approved for use against type A and B influenza viruses and requires only a single dose regardless of age. Xofluza has gained significant market share from Inavir in Japan, substantially reducing the sales of Inavir. This will significantly decrease the royalty payments we receive from Daiichi Sankyo Company, Limited.

~~The~~Our ~~following~~success isdepends alargely ~~summary~~upon ~~of the material U.S. federal income tax consequences of the acquisition, ownership and disposition of~~ our ~~common stock~~ability ~~and the pre-funded warrants and the acquisition, ownership, exercise, expiration or disposition of the common warrants, but does not purport~~ to beadvance aour ~~complete~~product ~~analysis~~candidates ofthrough ~~all~~ the ~~potential~~various ~~tax considerations~~stages ~~relating thereto. This summary is based upon the provisions~~ of ~~the~~drug ~~Internal Revenue Code of 1986, as amended, or the Code, Treasury Regulations promulgated thereunder, administrative rulings and judicial decisions, all as of the date hereof~~development. ~~These~~If ~~authorities~~we ~~may~~are beunable ~~changed or subject~~ to ~~differing~~successfully ~~interpretations,~~advance possibly with retroactive effect, so as to result in U.S. federal income tax consequences different from those set forth below. We have not sought and will not seek any ruling from the Internal Revenue Service, or ~~the~~develop ~~IRS,~~our ~~with~~product ~~respect to the statements made and the conclusions reached in the following summary~~candidates, ~~and~~our ~~there~~business ~~can~~will be nomaterially ~~assurance that the IRS or a court will agree with such statements and conclusions~~harmed.

~~This summary~~Even ~~also~~though ~~does~~we ~~not~~generate ~~address~~royalty revenue from a commercialized influenza product, all of our remaining product candidates are in early stages of development and their commercial viability remains subject to the ~~tax~~successful ~~considerations~~outcome ~~arising~~of ~~under~~future preclinical studies, clinical trials, manufacturing processes, regulatory approvals and the ~~laws~~risks generally inherent in the development of ~~any~~pharmaceutical Uproduct candidates.S. ~~state~~Failure orto ~~local~~advance the development of one or ~~any~~more ~~non-U~~of our product candidates may have a material adverse effect on our business.S. ~~jurisdiction~~For example, ~~estate~~the orPhase ~~gift~~2 ~~tax~~trial of teslexivir, a product acquired through the ~~3.8%~~merger ~~Medicare~~with ~~tax~~Aviragen, onwas ~~net investment~~costly ~~income~~and ordiverted ~~any~~resources ~~alternative~~from ~~minimum~~our ~~tax~~other ~~consequences.~~product Incandidates ~~addition~~and did not achieve the primary efficacy endpoint, ~~this~~resulting ~~discussion~~in ~~does~~abandonment ~~not~~of ~~address~~development ~~tax~~activities. ~~considerations~~The ~~applicable~~long-term success of our business ultimately depends upon our ability to aadvance ~~holder's~~the ~~particular~~development ~~circumstances~~of our product candidates through preclinical studies and clinical trials, appropriately formulate and consistently manufacture them in accordance with strict specifications and regulations, obtain approval of our product candidates for sale by the FDA or tosimilar regulatory authorities in other countries, and ultimately have our product candidates successfully commercialized, either by us or by a ~~holder~~strategic ~~that may~~partner or licensee. We cannot be ~~subject~~sure tothat ~~special~~the ~~tax~~results ~~rules~~of our ongoing or future research, ~~including~~preclinical studies or clinical trials will support or justify the continued development of our product candidates, ~~without~~or ~~limitation:~~that we will ultimately receive approval from the FDA, or similar regulatory authorities in other countries, to advance the development of our product candidates.

Our product candidates must satisfy rigorous regulatory standards of safety, efficacy and manufacturing before we can advance or complete their development and before they can be approved for sale by the FDA or similar regulatory authorities in other countries. To satisfy these standards, we must engage in expensive and lengthy studies and clinical trials, develop acceptable and cost-effective manufacturing processes, and obtain regulatory approval of our product candidates. Despite these efforts, our product candidates may not:

●	demonstrate clinically meaningful therapeutic or other medical benefits as compared to a patient receiving no treatment or over existing drugs or other product candidates in development to treat the same patient population;

●	be shown to be safe and effective in future preclinical studies or clinical trials;

●	have the desired therapeutic or medical effects;

●	be tolerable or free from undesirable or unexpected side effects;

●	meet applicable regulatory standards;

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~~In addition,~~● ifbe acapable ~~partnership, including any entity or arrangement classified as a partnership for U.S. federal income tax purposes, holds our common stock, pre-funded warrants or common warrants, the tax treatment~~ of abeing ~~partner~~appropriately ~~generally~~formulated ~~will depend on the status of the partner, the activities of the partnership,~~ and ~~certain~~manufactured ~~determinations~~in ~~made~~commercially atsuitable ~~the~~quantities ~~partner level. Accordingly, partnerships that hold our common stock, pre-funded warrants~~ or ~~common~~scale ~~warrants,~~ and ~~partners~~at inan ~~such~~acceptable ~~partnerships,~~cost; ~~should consult their tax advisors regarding the U.S. federal income tax consequences to them of the purchase, ownership, and disposition of our common stock, pre-funded warrants~~ or ~~common warrants.~~

~~You are~~● ~~urged~~be tosuccessfully ~~consult your tax advisor with respect to the application of the U.S. federal income tax laws to your particular situation~~commercialized, aseither ~~well~~by asus ~~any~~or ~~tax~~by ~~consequences of the purchase, ownership and disposition of~~ our ~~common~~licensees ~~stock, pre-funded warrants~~ or ~~common warrants arising under the U~~collaborators.~~S. federal estate or gift tax rules or under the laws of any U.S. state or local or any non-U.S. or other taxing jurisdiction or under any applicable tax treaty.~~

~~Definition~~Even if we demonstrate favorable results in preclinical studies and early-stage clinical trials, we cannot be sure that the results of late-stage clinical trials will be sufficient to support the continued development of our product candidates. Many, if not most, companies in the pharmaceutical and biopharmaceutical industries have experienced significant delays, setbacks and failures in all stages of development, including late-stage clinical trials, even after achieving promising results in preclinical testing or early-stage clinical trials. Accordingly, results from completed preclinical studies and early-stage clinical trials of our product candidates may not be predictive of the results we may obtain in future late-stage trials. Furthermore, even if the data collected from preclinical studies and clinical trials involving any of our product candidates demonstrate a satisfactory safety, tolerability and efficacy profile, such results may not be sufficient to obtain regulatory approval from the FDA in the U.S., ~~Holder~~ or other similar regulatory agencies in other jurisdictions, which is required to market and sell the product.

~~For~~If ~~purposes~~the ofactual ~~this~~or ~~summary,~~perceived atherapeutic ~~"U.S. Holder" is any beneficial owner of our common stock~~benefits, ~~pre-funded~~or ~~warrants~~the safety or ~~common~~tolerability ~~warrants~~profile ~~that~~of isany ~~a "U.S.~~of ~~person,"~~our ~~and~~product iscandidates are not aequal ~~partnership,~~to or ansuperior ~~entity~~to ~~treated~~other ascompeting atreatments ~~partnership~~approved orfor ~~disregarded~~sale ~~from~~or ~~its~~in ~~owner~~clinical development, ~~each~~we ~~for~~may ~~U.S.~~terminate ~~federal~~the ~~income~~development ~~tax~~of ~~purposes. A U.S. person is~~ any ~~person~~of ~~that,~~our ~~for~~product ~~U.S. federal~~candidates ~~income~~at ~~tax~~any ~~purposes~~time, isand orour isbusiness ~~treated~~prospects asand ~~any~~potential ofprofitability ~~the~~could ~~following:~~be harmed.

~~For purposes~~We ofare ~~this~~aware ~~summary,~~of a ~~"Non-U.S.~~number ~~Holder"~~of iscompanies ~~any~~marketing ~~beneficial~~or ~~owner~~developing ofvarious ~~our~~classes ~~common~~of ~~stock, pre~~anti-~~funded~~infective ~~warrants~~product candidates or ~~common~~products ~~warrants~~for the treatment of patients infected with HPV that isare ~~not~~either aapproved ~~U.S.~~for ~~Holder~~sale or afurther ~~partnership,~~advanced orin ~~other entity~~clinical ~~treated~~development asthan aours, ~~partnership~~such orthat ~~disregarded~~their ~~from~~time ~~its~~to ~~owner,~~approval ~~each~~and ~~for~~commercialization ~~U.S.~~may ~~federal~~be ~~income~~shorter ~~tax~~than ~~purposes.~~that for our product candidates.

~~Treatment~~If at any time we believe that any of ~~Pre-funded~~our ~~Warrants~~ product candidates may not provide meaningful or differentiated therapeutic benefits, perceived or real, equal to or better than our competitors’ products or product candidates, or we believe that our product candidates may not have as favorable a safety or tolerability profile as potentially competitive compounds, we may delay or terminate the future development of any of our product candidates. We cannot provide any assurance that the future development of any of our product candidates will demonstrate any meaningful therapeutic benefits over potentially competitive compounds currently approved for sale or in development, or an acceptable safety or tolerability profile sufficient to justify their continued development.

~~Although~~Our itproduct iscandidates ~~not~~may ~~entirely~~exhibit ~~free~~undesirable ~~from~~side ~~doubt,~~effects awhen ~~pre-funded~~used ~~warrant~~alone ~~should~~or ~~be treated as a share of our common stock for U.S. federal income tax purposes and a holder of pre-funded warrants should generally be taxed~~ in ~~the~~combination ~~same~~with ~~manner~~other asapproved apharmaceutical ~~holder of common stock~~products, aswhich ~~described~~may ~~below.~~delay ~~Accordingly, no gain~~ or ~~loss~~preclude ~~should~~their bedevelopment ~~recognized~~or ~~upon~~regulatory ~~the exercise~~approval of a pre-funded warrant and, upon exercise, the holding period of a pre-funded warrant should carry over to the share of common stock received. Similarly, the tax basis of the pre-funded warrant should carry over to the share of common stock received upon exercise, increased by the exercise price of $0.10 per share. Each holder should consult his, her or ~~its~~limit ~~own~~their ~~tax~~use ~~advisor~~if ~~regarding the~~ever ~~risks associated with the acquisition of pre-funded warrants pursuant to this offering (including potential alternative characterizations)~~approved. ~~The balance of this discussion generally assumes that the characterization described above is respected for U.S. federal income tax purposes.~~

~~Allocation~~Throughout the drug development process, we must continually demonstrate the activity, safety and tolerability of ~~Purchase~~our ~~Price~~ product candidates in order to obtain regulatory approval to further advance their clinical development, or to eventually market them. Even if our product candidates demonstrate adequate biologic activity and clear clinical benefit, any unacceptable side effects or adverse events, when administered alone or in the presence of other pharmaceutical products, may outweigh these potential benefits. We may observe adverse or serious adverse events or drug-drug interactions in preclinical studies or clinical trials of our product candidates, which could result in the delay or termination of their development, prevent regulatory approval, or limit their market acceptance if they are ultimately approved.

For U.S. federal income tax purposes, each share of our common stock and the associated common warrant and each pre-funded warrant and the associated common warrant should be treated

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~~for U.S.~~If ~~federal~~the ~~income~~results ~~tax~~from ~~purposes~~preclinical asstudies anor ~~investment~~clinical ~~unit~~trials ~~consisting~~ of ~~one~~our ~~share~~product ofcandidates, ~~common~~including ~~stock~~those ~~and~~that ~~the~~are ~~associated~~subject ~~common~~to ~~warrant~~existing ~~and~~or ~~one~~future ~~pre-funded~~license ~~warrant and the associated common warrant. Each holder must allocate the purchase price of such unit between each share of common stock~~ or ~~pre-funded~~collaboration ~~warrant~~agreements, asare ~~applicable~~unfavorable, ~~and~~we ~~the~~could ~~common~~be ~~warrant~~delayed ~~based~~or onprecluded ~~the~~from ~~relative fair market value of each at~~ the ~~time~~further ofdevelopment ~~issuance.~~or ~~The~~commercialization ~~price allocated to each share~~ of ~~common~~our ~~stock~~product ~~and pre-funded warrant and common warrant generally will be the holder's tax basis in such share or warrant~~candidates, aswhich ~~the~~could ~~case~~materially ~~may~~harm ~~be.~~our business.

~~Tax~~In ~~Consequences~~order to Ufurther advance the development of, and ultimately receive marketing approval to sell, our product candidates, we must conduct extensive preclinical studies and clinical trials to demonstrate their safety and efficacy to the satisfaction of the FDA or similar regulatory authorities in other countries, as the case may be.S Preclinical studies and clinical trials are expensive, complex, can take many years to complete, and have highly uncertain outcomes. ~~Holders~~ Delays, setbacks, or failures can and do occur at any time, and in any phase of preclinical or clinical testing, and can result from concerns about safety, tolerability, toxicity, a lack of demonstrated biologic activity or improved efficacy over similar products that have been approved for sale or are in more advanced stages of development, poor study or trial design, and issues related to the formulation or manufacturing process of the materials used to conduct the trials. The results of prior preclinical studies or early-stage clinical trials are not predictive of the results we may observe in late-stage clinical trials. In many cases, product candidates in clinical development may fail to show the desired tolerability, safety and efficacy characteristics, despite having favorably demonstrated such characteristics in preclinical studies or early-stage clinical trials.

~~Distributions~~In onaddition, ~~Common~~we ~~Stock~~ may experience numerous unforeseen events during, or as a result of, preclinical studies and the clinical trial process, which could delay or impede our ability to advance the development of, receive marketing approval for, or commercialize our product candidates, including, but not limited to:

As● ~~discussed~~communications ~~above~~with ~~under~~the ~~"Dividend Policy~~FDA," weor dosimilar ~~not~~regulatory ~~currently~~authorities ~~expect~~in todifferent ~~make~~countries, ~~distributions~~regarding ~~on our common stock. In~~ the ~~event~~scope ~~that we do make distributions of cash~~ or ~~other~~design ~~property, distributions paid on common stock, other than certain pro rata distributions~~ of ~~common stock, will be treated as~~ a ~~dividend~~trial toor ~~the~~trials, ~~extent paid out of our current~~ or ~~accumulated~~placing ~~earnings and profits and will be includible in income by~~ the ~~U.S.~~development ~~Holder~~of ~~and taxable as ordinary income when received. If~~ a ~~distribution~~product ~~exceeds~~candidate ~~our~~on ~~current~~clinical ~~and~~hold ~~accumulated earnings~~or ~~and~~delaying ~~profits,~~ the ~~excess~~next ~~will~~phase ~~be first treated as a tax-free return~~ of ~~the~~development ~~U.S.~~until ~~Holder's~~questions ~~investment,~~or upissues toare ~~the~~satisfactorily ~~U.S. Holder's tax basis in the common stock. Any remaining excess will be treated as a capital gain. Subject to applicable limitations~~resolved, ~~dividends~~including ~~paid~~performing toadditional ~~certain~~studies ~~non-corporate U.S. Holders may be eligible for taxation as "qualified dividend income" and therefore may be taxable at rates applicable~~ to ~~long-term~~answer ~~capital gains. U.S. Holders should consult~~ their tax advisers regarding the availability of the reduced tax rate on dividends in their particular circumstances. Dividends received by a corporate U.S. Holder will be eligible for the dividends-received deduction if the U.S. Holder meets certain holding period and other applicable requirements. queries;

~~Constructive~~● ~~Dividends~~regulatory onauthorities ~~Common~~or ~~Warrants~~ IRBs not authorizing us to commence or conduct a clinical trial at a prospective trial site;

If● weenrollment ~~were~~in ~~to pay a taxable dividend to~~ our ~~shareholders~~clinical ~~and,~~trials inbeing ~~accordance with the anti-dilution provisions of the common warrants~~delayed, ~~the exercise~~or ~~price~~proceeding ofat ~~the common warrants were decreased, that decrease would be deemed to be the payment of~~ a ~~taxable~~slower ~~dividend~~pace tothan awe ~~U.S. Holder of the common warrants to the extent of our current or accumulated earnings and profits~~expected, ~~notwithstanding~~because ~~the~~we ~~fact~~have ~~that~~difficulty ~~the~~recruiting ~~U.S.~~participants ~~Holder will not receive a cash payment. If the exercise price is adjusted in certain other circumstances (~~or inparticipants ~~certain circumstances,~~drop ~~there~~out ~~is a failure to make adjustments), that adjustment may also result in the deemed payment~~ of aour ~~taxable~~clinical ~~dividend~~trials toat a ~~U.S.~~higher ~~Holder.~~rate ~~U.S.~~than ~~Holders~~we ~~should consult their tax advisers regarding the proper treatment of any adjustments to the common warrants.~~ anticipated;

~~Sale~~● orour ~~Other~~third-party ~~Disposition~~contractors, upon whom we rely to conduct preclinical studies, clinical trials and the manufacturing of ~~Common~~our ~~Stock~~ clinical trial materials, failing to comply with regulatory requirements or meet their contractual obligations to us in a timely manner;

~~For~~● ~~U.S.~~having ~~federal~~to ~~income~~suspend ~~tax purposes, gain~~ or ~~loss~~ultimately ~~realized~~terminate ona ~~the~~clinical ~~sale~~trial ~~or other disposition of common stock will be capital gain or loss, and will be long-term capital gain or loss~~ if ~~the~~participants ~~U.S.~~are ~~Holder~~being ~~held~~exposed ~~the~~to ~~common~~unacceptable ~~stock~~health ~~for more than one year. The amount of the gain~~ or ~~loss~~safety will equal the difference between the U.S. Holder's tax basis in the common stock disposed of and the amount realized on the disposition. Long-term capital gains recognized by non-corporate U.S. Holders will be subject to reduced tax rates. The deductibility of capital losses is subject to limitations. risks;

~~Sale~~● regulatory authorities or ~~Other~~IRBs ~~Disposition~~requiring that we hold, ~~Exercise~~suspend or ~~Expiration~~terminate ofour ~~Common~~preclinical ~~Warrants~~ studies and clinical trials for various reasons, including non-compliance with regulatory requirements; and

~~For~~● ~~U.S. federal income tax purposes, gain or loss realized on~~ the ~~sale~~supply or ~~other~~quality ~~disposition~~ of amaterial ~~common~~necessary ~~warrant~~to ~~(other~~conduct ~~than~~our bypreclinical ~~exercise)~~studies ~~will be capital gain~~ or ~~loss~~clinical ~~and~~trials ~~will~~being beinsufficient, ~~long-term~~inadequate ~~capital gain~~ or ~~loss if the U~~unavailable.S. Holder held the warrant for more than one year at the time of the sale or other disposition. The amount of the gain or loss will equal the difference between the U.S. Holder's tax basis in the common warrant disposed of and the amount realized on the disposition.

Even if the data collected from preclinical studies or clinical trials involving our product candidates demonstrate a satisfactory tolerability, safety and efficacy profile, such results may not be sufficient to support the submission of a BLA or NDA to obtain regulatory approval from the FDA in the U.S., or other similar regulatory authorities in other foreign jurisdictions, which is required for us to market and sell our product candidates.

We have a limited capacity for managing clinical trials, which could delay or impair our ability to initiate or complete clinical trials of our product candidates on a timely basis and materially harm our business.

We have a limited capacity to recruit and manage all of the clinical trials necessary to obtain approval for our product candidates by the FDA or similar regulatory authorities in other countries. By contrast, larger pharmaceutical and biopharmaceutical companies often have substantial staff or departments with extensive experience in conducting clinical trials with multiple product candidates across multiple indications and obtaining regulatory approval in various countries. In addition, these companies may have greater financial resources to compete for the same clinical investigators, sites and patients that we are attempting to recruit for our clinical trials. As a result, we may be at a competitive disadvantage that could delay the initiation, recruitment, timing and completion of our clinical trials and obtaining of marketing approvals, if achieved at all, for our product candidates.

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~~In general,~~Our aindustry ~~U.S.~~is ~~Holder~~highly ~~will~~competitive ~~not~~and besubject ~~required~~ to ~~recognize~~rapid ~~income,~~technological ~~gain~~changes. orAs ~~loss upon the exercise of~~ a ~~common warrant by payment of the exercise price~~result, ~~except~~we tomay ~~the extent of cash paid in lieu of a fractional share. A U.S. Holder's tax basis in a share of common stock received upon exercise will~~ be ~~equal~~unable to ~~the~~compete ~~sum~~successfully ofor ~~(1) the~~develop ~~U.S.~~innovative ~~Holder's tax basis in the common warrant and (2) the exercise price of the common warrant. A U.S. Holder's holding period in the stock received upon exercise will commence on the day~~ or ~~the~~differentiated ~~day after such U.S. Holder exercises the common warrant. No discussion is provided herein regarding the U.S. federal income tax treatment on the exercise of a common warrant on a cashless basis~~products, ~~and~~which ~~U.S.~~could ~~Holders~~harm ~~are~~our ~~urged to consult their tax advisors as to the exercise of a common warrant on a cashless basis~~business.

~~If a~~Our ~~common~~industry ~~warrant~~is ~~expires~~highly ~~without~~competitive ~~being~~and ~~exercised,~~characterized aby Urapid technological change.S. ~~Holder~~Key ~~will~~competitive ~~recognize~~factors ain ~~capital~~our ~~loss~~industry ininclude, anamong ~~amount~~others, ~~equal~~the ability to ~~such~~successfully ~~U.S.~~advance ~~Holder's~~the ~~tax~~development ~~basis~~of ina product candidate through preclinical and clinical trials; the ~~common~~efficacy, ~~warrant.~~toxicology, ~~This~~tolerability, ~~loss~~safety, ~~will be~~resistance ~~long~~or cross-~~term~~resistance, ~~capital~~interaction ~~loss~~or ~~if,~~dosing atprofile of a product or product candidate; the ~~time~~timing and scope of ~~the~~marketing ~~expiration~~approvals, ~~the~~if ~~U.S.~~ever ~~Holder's~~achieved; ~~holding~~reimbursement ~~period~~rates infor and the ~~common~~average ~~warrant~~selling isprice ~~more~~of ~~than~~competing ~~one~~products ~~year.~~and ~~The~~pharmaceutical ~~deductibility~~products in general; the availability of ~~capital~~raw ~~losses~~materials isand ~~subject~~qualified contract manufacturing and manufacturing capacity to ~~limitations.~~ produce our product candidates; relative manufacturing costs; establishing, maintaining and protecting our intellectual property and patent rights; and sales and marketing capabilities.

~~Tax~~Developing ~~Consequences~~pharmaceutical product candidates is a highly competitive, expensive and risky activity with a long business cycle. Many organizations, including the large pharmaceutical and biopharmaceutical companies that have existing products on the market or in clinical development that may compete with our product candidates, have substantially more resources than us, as well as much greater capabilities and experience than we have in research and discovery, designing and conducting preclinical studies and clinical trials, operating in a highly regulated environment, formulating and manufacturing drug substances, products and devices, and marketing and sales. Our competitors may be more successful than us in obtaining regulatory approvals for their product candidates and achieving broad market acceptance once they are approved. Our competitors’ products or product candidates may be more effective, have fewer adverse effects, be more convenient to ~~Non~~administer, have a more favorable resistance profile, or be more effectively marketed and sold than any product that we, or our potential future licensees or collaborators, may develop or commercialize. New drugs or classes of drugs from competitors may render our product candidates obsolete or non-Ucompetitive before we are able to successfully develop them or, if approved, before we can recover the expenses of developing and commercializing them.S We anticipate that we, or our potential future licensees or collaborators, will face intense and increasing competition as new drugs and drug classes enter the market and advanced technologies or new drug targets become available. ~~Holders~~ If our product candidates do not demonstrate any meaningful competitive advantages over existing products, or new products or product candidates, we may terminate the development or commercialization of our product candidates at any time.

~~Distributions~~ Our competitors, either alone or with their collaborators, may succeed in developing product candidates or products that are more effective, safer, less expensive or easier to administer than ours. Accordingly, our competitors may succeed in obtaining regulatory approval for their product candidates more rapidly than we can. Companies that can complete clinical trials, obtain required marketing approvals and commercialize their products before their competitors do so may achieve a significant competitive advantage, including certain patent and marketing exclusivity rights that could delay the ability of competitors to market certain products.

AsWe ~~discussed~~also inface, ~~the~~and ~~section~~expect ~~titled~~that ~~"Dividend Policy,"~~ we dowill ~~not~~continue ~~anticipate~~to ~~paying~~face, ~~any~~intense ~~dividends~~competition onfrom ~~our~~other ~~common~~companies ~~stock~~ in ~~the~~a ~~foreseeable~~number ~~future. If~~of weother ~~make~~areas, ~~distributions~~including ~~on our common stock or constructive dividends on our common warrants~~ (asi) ~~described~~attracting ~~above~~larger ~~under~~pharmaceutical ~~"Constructive~~and ~~Dividends~~biopharmaceutical oncompanies ~~Common~~to ~~Warrants"),~~enter ~~those~~into ~~payments~~collaborative ~~will~~arrangements ~~constitute dividends~~with ~~for~~us ~~U.S. federal income tax purposes~~ to ~~the~~acquire, ~~extent~~license ~~we have current~~ or ~~accumulated~~co-develop ~~earnings~~our ~~and~~product ~~profits~~candidates, as(ii) ~~determined~~identifying ~~under~~and ~~U.S.~~obtaining ~~federal~~additional ~~income~~clinical-stage ~~tax~~development ~~principles.~~programs Toto ~~the~~bolster ~~extent those distributions exceed both~~ our ~~current~~pipeline, ~~and~~(iii) ~~our~~attracting ~~accumulated~~investigators ~~earnings~~ and ~~profits,~~clinical ~~they~~sites ~~will~~capable ~~constitute~~of aconducting ~~return~~our ofclinical ~~capital~~trials, and ~~will~~(iv) ~~first~~recruiting ~~reduce~~patients ~~a Non-U.S.~~to ~~Holder's~~participate ~~basis~~ in our ~~common~~clinical ~~stock or common warrants, as applicable, but not below zero~~trials. ~~Any~~There ~~excess~~can ~~will~~ be ~~treated~~no asassurance ~~capital~~that ~~gain~~product ~~and~~candidates ~~will~~resulting befrom ~~treated~~our asresearch ~~described~~and ~~below~~development ~~under~~efforts, or ~~the "—Gain~~from onjoint ~~Sale~~efforts orwith ~~Other~~our ~~Disposition~~potential offuture ~~Common~~licensees ~~Stock~~ or ~~Common~~collaborators, ~~Warrants"~~will ~~section. Any such distributions would~~ be ~~subject~~able to ~~the~~compete ~~discussions~~successfully ~~below~~with ~~regarding~~our ~~back-up~~competitors’ ~~withholding~~existing ~~and~~products ~~Foreign Account~~or ~~Tax~~product ~~Compliance~~candidates ~~Act,~~in ~~or FATCA~~development.

Subject to the discussion below on effectively connected income, any dividend paid to a Non-U.S. Holder generally will be subject to U.S. withholding tax either at a rate of 30% of the gross amount of the dividend or such lower rate as may be specified by an applicable income tax treaty. To receive a reduced treaty rate, a Non-U.S. Holder must provide us or our agent with an IRS Form W-8BEN (generally including a U.S. taxpayer identification number), IRS Form W-8 BEN-E or another appropriate version of IRS Form W-8 (or a successor form), which must be updated periodically, and which, in each case, must certify qualification for the reduced rate. Non-U.S. Holders should consult their tax advisors regarding their entitlement to benefits under any applicable income tax treaty.

Dividends paid to a Non-U.S. Holder that are effectively connected with the Non-U.S. Holder's conduct of a trade or business within the United States and that are not eligible for relief from U.S. (net basis) income tax under an applicable income tax treaty, generally are exempt from the (gross basis) withholding tax described above. To obtain this exemption from withholding tax, the Non-U.S. Holder must provide the applicable withholding agent with an IRS Form W-8ECI or successor form or other applicable IRS Form W-8 certifying that the dividends are effectively connected with the Non-U.S. Holder's conduct of a trade or business within the United States. Such effectively connected dividends, if not eligible for relief under a tax treaty, would not be subject to a withholding tax, but would be taxed at the same graduated rates applicable to U.S. persons, net of certain deductions and credits and if, in addition, the Non-U.S. Holder is a corporation, may also be subject to a branch profits tax at a rate of 30% (or such lower rate as may be specified by an applicable income tax treaty).

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~~In the~~We ~~case~~may ofbe ~~any~~unable ~~constructive dividend (as described above under "—Tax Consequences~~ to ~~U.S.~~successfully ~~Holders—Constructive~~develop ~~Dividends~~a onproduct ~~Common~~candidate ~~Warrants"),~~that it is ~~possible that~~ the ~~U.S.~~subject ~~federal tax on the constructive dividend would be withheld from shares~~ of ~~common~~an ~~stock,~~existing ~~sales~~or ~~proceeds~~future ~~subsequently~~license ~~paid~~agreement or ~~credited,~~collaboration orif ~~other~~our ~~amounts~~licensee ~~payable~~ or ~~distributable~~collaborator todoes ~~a Non-U.S.~~not ~~Holder.~~perform ~~Non-U.S.~~or ~~Holders~~fulfill ~~who~~its ~~are~~contractual ~~subject~~obligations, todelays ~~withholding~~the ~~tax~~development ~~under~~of ~~such~~our ~~circumstances~~product ~~should~~candidate, ~~consult their tax advisers as to whether it can obtain a refund for all~~ or aterminates ~~portion of~~ the ~~withholding~~ ~~tax~~agreement.

~~If you~~We ~~are~~expect ~~eligible~~to ~~for~~continue ato ~~reduced~~enter ~~rate~~into ofand ~~withholding~~rely ~~tax~~on ~~pursuant~~license toand acollaboration ~~tax~~agreements ~~treaty~~in the future, ~~you~~or ~~may~~other besimilar ~~able~~business arrangements with third parties, to ~~obtain~~further adevelop ~~refund~~and/or commercialize some or all of ~~any~~our ~~excess~~existing ~~amounts~~and ~~withheld~~future ifproduct ~~you~~candidates. ~~timely~~Such ~~file~~licensees anor ~~appropriate claim~~collaborators ~~for~~may ~~refund~~not perform as agreed upon or anticipated, may fail to comply with strict regulations, or may elect to delay or terminate their efforts in developing or commercializing our product candidates even though we have met our obligations under the ~~IRS~~arrangement.

~~Exercise~~A majority of the potential revenue from existing and any future licenses and collaborations we may enter into will likely consist of contingent milestone payments, such as payments received for achieving development or ~~Expiration~~regulatory milestones, and royalties payable on the sales of ~~Common~~approved ~~Warrants~~ products. Milestone and royalty revenues that we may receive under these licenses and collaborations will depend primarily upon our licensees’ or collaborators’ ability to successfully develop and commercialize our product candidates. In addition, our licensees or collaborators may decide to enter into arrangements with third parties to commercialize products developed under our existing or future collaborations using our technologies, which could reduce the milestone and royalty revenue that we may receive, if any. In many cases, we will not be directly or closely involved in the development or commercialization of our product candidates that are subject to licenses or collaborations and, accordingly, we will depend largely on our licensees or collaborators to develop or commercialize our product candidates. Our licensees may encounter competition from new products entering the market, which could adversely affect our royalty income. Our licensees or collaborators may fail to develop or effectively commercialize our product candidates because they:

In● ~~general,~~do anot ~~Non-U.S.~~allocate ~~Holder~~the ~~will~~necessary ~~not~~resources bedue ~~required~~ to ~~recognize~~internal ~~income~~constraints, ~~gain~~such oras ~~loss~~limited ~~upon~~personnel with the ~~exercise~~requisite ofscientific aexpertise, ~~common~~limited ~~warrant~~capital byresources, ~~payment~~or of the ~~exercise~~ ~~price,~~belief ~~except~~that toother ~~the~~product ~~extent~~candidates ofor ~~cash~~internal ~~paid~~programs inmay ~~lieu~~have of a ~~fractional~~higher ~~share.~~likelihood ~~However, no discussion is provided herein regarding the U.S. federal income tax treatment on the exercise~~ of aobtaining ~~common warrant~~regulatory ~~on a cashless basis~~approval, ~~and~~or ~~Non-U.S.~~may ~~Holders~~potentially ~~are~~generate ~~urged to consult their tax advisors as to the exercise of~~ a ~~common~~greater ~~warrant~~return on ~~a cashless basis.~~ investment;

~~If a~~● ~~common~~do ~~warrant~~not ~~expires~~have ~~without~~sufficient ~~being~~resources ~~exercised,~~necessary ~~a Non-U.S. Holder that is engaged in a U.S. trade or business~~ to ~~which~~fully ~~any~~support ~~income from~~ the ~~common~~product ~~warrant~~candidate ~~would~~through beclinical ~~effectively connected~~development, orregulatory ~~who~~approval ~~is present in the United States for a period or periods aggregating 183 days or more during the calendar year in which the expiration occurs (~~and ~~certain other conditions are met) will recognize a capital loss in an amount equal to such Non-U.S. Holder's tax basis in the common warrant.~~ commercialization;

~~Gain~~● onare ~~Sale~~unable orto ~~Other~~obtain ~~Disposition~~the ofnecessary ~~Common~~regulatory ~~Stock~~approvals; or ~~Common Warrants~~

~~Subject~~● toprioritize ~~the~~other ~~discussion~~programs ~~below~~or ~~regarding~~otherwise ~~backup~~diminish ~~withholding~~their ~~and~~support ~~FATCA,~~for adeveloping ~~Non-U.S.~~and/or ~~Holder~~marketing ~~generally~~our ~~will~~product ~~not~~candidate beor ~~required~~product due to ~~pay~~a ~~U.S.~~change ~~federal income~~in ~~tax~~management, onbusiness ~~any~~operations ~~gain realized upon the sale~~ or ~~other disposition of our common stock or common warrants unless:~~strategy.

Should any of these events occur, we may not realize the full potential or intended benefit of our license or collaboration arrangements, and our results of operations may be adversely affected. In addition, a licensee or collaborator may decide to pursue the development of a competitive product candidate developed outside of our agreement with them. Conflicts may also arise if there is a dispute about the progress of, or other activities related to, the clinical development or commercialization of a product candidate, the achievement and payment of a milestone amount, the ownership of intellectual property that is developed during the course of the arrangement, or other license agreement terms. If a licensee or collaborator fails to develop or effectively commercialize our product candidates for any of these reasons, we may not be able to replace them with another third party willing to develop and commercialize our product candidates under similar terms, if at all. Similarly, we may disagree with a licensee or collaborator as to which party owns newly or jointly-developed intellectual property. Should an agreement be revised or terminated as a result of a dispute and before we have realized the anticipated benefits of the arrangement, we may not be able to obtain certain development support or revenues that we anticipated receiving. We may also be unable to obtain, on terms acceptable to us, a license from such collaboration partner to any of its intellectual property that may be necessary or useful for us to continue to develop and commercialize the product candidate. There can be no assurance that any product candidates will emerge from any existing or future license or collaboration agreements we may enter into for any of our product candidates.

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~~of our~~If ~~common~~government stock will not be subject to United States federal income tax if (A) in the case of our common stock, (a) shares of our common stock are "regularly traded," as defined by applicable Treasury Regulations, on an established securities market, such as Nasdaq, and ~~(b) the Non~~third-~~U.S.~~party ~~Holder~~payers ~~owns~~fail orto ~~owned,~~provide ~~actually~~adequate ~~and~~reimbursement ~~constructively, 5%~~ or ~~less~~coverage offor ~~the shares of~~ our ~~common~~ ~~stock~~products ~~throughout the five-year period ending on the date of the sale~~ or ~~exchange;~~those and (B) in the case of our common warrants, either (a)(i) shares of our common stock are "regularly traded," as defined by applicable Treasury Regulations, on an established securities market, such as Nasdaq, (ii) our common warrants are not considered regularly traded on an established securities market and (iii) the Non-U.S. Holder does not own, actually or constructively, common warrants with a fair market value greater than the fair market value of 5% of the shares of our common stock, determined as of the date that ~~such Non-U.S. Holder acquired its common warrants, or (b)(i) our common warrants~~ are ~~considered~~developed ~~regularly~~through ~~traded~~licenses ~~on an established securities market, and (ii) the Non-U.S. Holder owns~~ or ~~owned~~collaborations, ~~actually and constructively, 5% or less of~~ our ~~common~~revenues warrants throughout the five-year period ending on the date of the sale or exchange. Our common warrants are not expected to be regularly traded on an established securities market. If the foregoing exception does not apply, such Non-U.S. Holder's proceeds received on the disposition of shares will generally be subject to withholding at a rate of 15% and ~~such~~potential ~~Non-U.S.~~for ~~Holder~~profitability ~~will~~may ~~generally~~ be ~~taxed on any gain in the same manner as gain that is effectively connected with the conduct of a U~~harmed.~~S. trade or business, except that the branch profits tax generally will not apply.~~

~~Information~~In ~~Reporting~~the U.S. and ~~Backup~~most ~~Withholding~~ foreign markets, product revenues or related royalty revenue, and therefore the inherent value of our products, will depend largely upon the reimbursement rates established by third-party payers for such products. Third-party payers include government health administration authorities, managed-care organizations, private health insurers and other similar organizations. Third-party payers are increasingly examining the cost effectiveness of medical products, services and pharmaceutical drugs and challenging the price of these products and services. In addition, significant uncertainty exists as to the reimbursement status, if any, of newly approved pharmaceutical products. Further, the comparative effectiveness of new products over existing therapies and the assessment of other non-clinical outcomes are increasingly being considered in the decision by payers to establish reimbursement rates. We, or our licensees or collaborators if applicable, may also be required to conduct post-marketing clinical trials in order to demonstrate the cost-effectiveness of our products. Such studies may require us to commit a significant amount of management time and financial resources. There can be no assurance that any products that we or our licensees or collaborators may successfully develop will be reimbursed in part, or at all, by any third-party payers in any country.

~~Information~~Many ~~returns~~governments ~~may~~continue beto ~~filed~~propose ~~with~~legislation designed to expand the ~~IRS~~coverage, yet reduce the cost, of healthcare, including pharmaceutical products. In many foreign markets, governmental agencies control the pricing of prescription drugs. In the U.S., significant changes in ~~connection~~federal ~~with~~health ~~distributions~~care policy were approved over the past several years and continue to evolve and will likely result in reduced reimbursement rates for many pharmaceutical products in the future. We expect that there will continue to be federal and state proposals to implement increased government control over reimbursement rates of pharmaceutical products. In addition, we expect that increasing emphasis on ~~common~~managed ~~stock~~care orand ~~constructive~~government ~~dividends~~intervention in the U.S. healthcare system will continue to put downward pressure on ~~common~~the ~~warrants,~~pricing of pharmaceutical products there. Recent events have resulted in increased public and governmental scrutiny of the ~~proceeds~~cost of adrugs, ~~sale~~especially orin ~~other~~connection ~~disposition~~with price increases following companies’ acquisitions of ~~common~~the ~~stock~~rights to certain drug products. AIn ~~non-exempt~~particular, U.S. ~~Holder~~federal ~~may~~prosecutors berecently ~~subject~~issued subpoenas to a pharmaceutical company seeking information about its drug pricing practices, among other issues, and members of the U.S. ~~backup~~Congress ~~withholding~~have onsought ~~these~~information ~~payments~~from certain pharmaceutical companies relating to post-acquisition drug-price increases. Our revenue and future profitability could be negatively affected if itthese ~~fails~~inquiries were to ~~provide~~result ~~its~~in ~~taxpayer~~legislative ~~identification number~~or regulatory proposals that limit our ability to increase the ~~withholding~~prices ~~agent~~of our products that may be approved for sale in the future. Legislation and ~~comply~~regulations ~~with~~affecting ~~certification~~the ~~procedures~~pricing orof ~~otherwise~~pharmaceutical ~~establish~~products anmay ~~exemption~~change ~~from~~before ~~backup~~our ~~withholding~~product candidates are approved for sale, which could further limit or eliminate their reimbursement rates. Further, social and patient activist groups, whose goal it is to reduce the cost of healthcare, and in particular the price of pharmaceutical products, may also place downward pressure on the price of these products, which could result in decreases in the price of our products.

~~A Non-U.S.~~If ~~Holder~~any ~~may~~product becandidates ~~subject to U.S. information reporting and backup withholding on these payments unless the Non-U.S. Holder complies with certification procedures to establish~~ that itwe isdevelop ~~not~~independently, aor ~~U.S.~~through ~~person~~licensees ~~(within~~or ~~the~~collaborators ~~meaning of the Code). The certification requirements generally will be satisfied~~ if ~~the Non-U.S. Holder provides the~~ applicable ~~withholding agent with a statement on the applicable IRS Form (or suitable substitute or successor form)~~, ~~together~~are ~~with~~approved ~~all~~but ~~appropriate~~do ~~attachments,~~not ~~signed~~gain ~~under~~meaningful ~~penalties~~acceptance ofin ~~perjury,~~their ~~stating,~~intended ~~among other things~~markets, ~~that~~we ~~such Non-U.S.~~are ~~Holder is~~ not alikely U.S. Person. Applicable Treasury Regulations provide alternative methods for satisfying this requirement. In addition, the amount of distributions on common stock or constructive dividends on common warrants paid to agenerate ~~Non-U.S.~~significant ~~Holder, and the amount of any U~~revenues.S. federal tax withheld therefrom, must be reported annually to the IRS and the holder. This information may be made available by the IRS under the provisions of an applicable tax treaty or agreement to the tax authorities of the country in which the Non-U.S. Holder resides.

~~Payment of~~Even ~~the~~if ~~proceeds~~our ofproduct ~~the~~candidates ~~sale~~are orsuccessfully ~~other~~developed ~~disposition~~and ofwe ~~common stock~~ or ~~common warrants to or through~~ a ~~non-U.S.~~licensee ~~office of a U.S. broker~~ or ofcollaborator aobtains ~~non-U.S.~~the ~~broker~~requisite ~~with~~regulatory ~~certain specified~~approvals ~~U.S. connections generally will be subject~~ to ~~information~~market ~~reporting~~them ~~requirements,~~in ~~but~~the ~~not backup withholding~~future, ~~unless~~they ~~the~~may ~~Non-U.S.~~not ~~Holder~~gain ~~certifies~~market ~~under~~acceptance ~~penalties~~or ofbroad ~~perjury~~utilization ~~that~~among itphysicians, ispatients ~~not a U.S. person~~ or anthird-party ~~exemption otherwise applies~~payers. ~~Payments~~The ofdegree ~~the proceeds~~ of amarket ~~sale~~acceptance orthat ~~other~~any ~~disposition~~ of ~~common~~our ~~stock~~products ormay ~~common~~achieve ~~warrants~~will todepend oron ~~through~~ a ~~U.S.~~number ~~office~~ of ~~a broker generally will be subject to information reporting and backup withholding~~factors, ~~unless the Non-U.S. Holder certifies under penalties of perjury that it is not a U.S. person or otherwise establishes an exemption.~~ including:

~~Backup withholding~~● isthe ~~not~~efficacy anor ~~additional~~perceived ~~tax.~~clinical ~~The~~benefit ~~amount~~ of ~~any backup withholding from a payment generally will be allowed as a credit against~~ the ~~holder's~~product, ~~U.S.~~if ~~federal~~any, ~~income~~relative ~~tax liability~~to ~~and~~existing therapies;

●	the timing of market approval and the existing market for competitive drugs, including the presence of generic drugs;

●	the level of reimbursement provided by third-party payers to cover the cost of the product to patients;

●	the net cost of the product to the user or third-party payer;

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~~may entitle~~● the ~~holder~~convenience toand aease ~~refund,~~of ~~provided~~administration ~~that~~of the ~~required information is timely furnished to the IRS.~~ product;

~~Foreign~~● ~~Accounts~~ the product’s potential advantages over existing or alternative therapies;

~~The~~● ~~Code generally imposes a U.S. federal withholding tax of 30% on dividends and, subject to~~ the ~~discussion~~actual below regarding proposed regulations recently issued by the U.S. Treasury Department, the gross proceeds of a disposition of our securities paid to a "foreign financial institution" (as specifically defined for this purpose), unless such institution enters into an agreement with the U.S. government to, among other things, withhold on certain payments and to collect and provide to the U.S. tax authorities substantial information regarding U.S. account holders of such institution (which includes certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with U.S. owners) or ~~otherwise~~perceived ~~qualifies~~safety ~~for an exemption from these rules. A U.S. federal withholding tax~~ of ~~30%~~similar ~~also~~classes ~~applies to dividends and, subject to the discussion below regarding proposed regulations recently issued by the U.S. Treasury Department, will apply to the gross proceeds~~ of a disposition of our securities paid to a non-financial foreign entity (as defined in the Code), unless such entity provides the withholding agent with either a certification that it does not have any substantial direct or indirect. products;

~~Under certain~~● ~~circumstances,~~the aactual ~~non-U.S. holder might be eligible for refunds~~ or ~~credits~~perceived ofexistence, ~~such~~incidence ~~taxes. An intergovernmental agreement between the United States~~ and anseverity ~~applicable~~of ~~foreign country~~adverse ~~may modify the requirements described in this paragraph.~~ effects;

~~The U.S.~~● ~~Treasury Department recently released proposed regulations which, if finalized in their present form, would eliminate~~ the ~~federal~~effectiveness ~~withholding tax~~ of ~~30% applicable to the gross proceeds of a sale or other disposition of our common stock. In its preamble to such proposed regulations~~sales, ~~the~~marketing U.S. Treasury Department stated that taxpayers may generally rely on the proposed regulations until final regulations are issued. Prospective investors should consult their own tax advisors regarding the possible impact of these rules on their investment in our common stock, and ~~the~~ ~~possible~~distribution ~~impact~~capabilities; ~~of these rules~~ and the proposed regulations on the entities through which they hold our common stock, including, without limitation, the process and deadlines for meeting the applicable requirements to prevent the imposition of this 30% withholding tax.

~~EACH PROSPECTIVE~~● ~~INVESTOR~~the ~~SHOULD~~scope ~~CONSULT~~of ~~ITS~~the ~~TAX~~product ~~ADVISOR~~label ~~REGARDING~~approved ~~THE~~by ~~PARTICULAR~~the ~~U.S.~~FDA ~~FEDERAL,~~or ~~STATE~~similar ~~AND~~regulatory ~~LOCAL~~agencies ~~AND~~in ~~NON-U.S.~~other ~~TAX CONSEQUENCES OF PURCHASING, HOLDING AND DISPOSING OF OUR SECURITIES, INCLUDING THE CONSEQUENCES OF ANY PROPOSED CHANGE IN APPLICABLE LAWS~~jurisdictions. IN ADDITION, SIGNIFICANT CHANGES IN U.S. FEDERAL TAX LAWS WERE RECENTLY ENACTED. PROSPECTIVE INVESTORS SHOULD ALSO CONSULT WITH THEIR TAX ADVISORS WITH RESPECT TO SUCH CHANGES IN U.S. TAX LAW AS WELL AS POTENTIAL CONFORMING CHANGES IN STATE TAX LAWS.

There can be no assurance that physicians will choose to prescribe or administer our products, if approved, to the intended patient population. If our products do not achieve meaningful market acceptance, or if the market for our products proves to be smaller than anticipated, we may never generate significant revenues.

Changes in funding for the FDA, the SEC and other government agencies could hinder their ability to hire and retain key leadership and other personnel, prevent new products and services from being developed or commercialized in a timely manner or otherwise prevent those agencies from performing normal functions on which the operation of our business may rely, which could negatively impact our business.

The ability of the FDA to review and approve new products can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept payment of user fees, and statutory, regulatory, and policy changes. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding of the SEC and other government agencies on which our operations may rely, including those that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable.

On January 20, 2025, President Trump signed an executive order creating an advisory commission, the “Department of Government Efficiency,” to reform federal government processes and reduce expenditures. Pressures on and uncertainty surrounding the U.S. federal government’s budget, and potential changes in budgetary priorities and spending levels, could adversely affect staffing levels and the funding for the FDA. Disruptions at the FDA and other agencies due to these policies may slow the time necessary for new drugs to be reviewed and/or approved by necessary government agencies, which would adversely affect our business. For example, over the past decade, the U.S. government has shut down, at least partially, several times and certain regulatory agencies, such as the FDA and the SEC, have had to furlough critical FDA, SEC and other government employees and stop critical activities. If a prolonged government shutdown occurs, it could significantly impact the ability of the FDA to timely review and process our regulatory submissions which could have a material adverse effect on our business. Further, future government shutdowns could impact our ability to access the public markets and obtain necessary capital in order to properly capitalize and continue our operations.

Risks Related to Dependence on Third Parties

Our dependence on third parties could delay or prevent the development, approval, manufacturing, or any eventual commercialization of our product candidates.

We depend on third-party collaborators, service providers, and others in the research, development, manufacturing, and any eventual commercialization of our product candidates. We rely heavily on these parties for multiple aspects of our drug development and manufacturing activities and anticipate that we will rely on third parties for commercialization activities including testing of our product candidates. We have very limited control over many aspects of those activities. Failure by one or more of the third-party collaborators, service providers, or others to complete activities on schedule or in accordance with our expectations or to meet their contractual or other obligations to us; failure of one or more of these parties to comply with applicable laws or regulations; or any disruption in the relationships between us and these parties, could delay or prevent the development, approval, manufacturing, or any eventual commercialization of our product candidates, expose us to suboptimal quality of service delivery or deliverables, result in repercussions such as missed deadlines or other timeliness issues, erroneous data and supply disruptions, and could also result in non-compliance with legal or regulatory requirements or industry standards or subject us to reputational harm, all with potential negative implications for our product pipeline and business.

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We rely ~~LEGAL~~on ~~MATTERS~~ third-party contract manufacturers for certain portions of our manufacturing process. If third-party contract manufacturers fail to manufacture according to our specifications, or fail to comply with strict government regulations, our preclinical studies or clinical trials could be adversely affected and the development of our product candidates could be delayed or terminated, or we could incur significant additional expenses.

~~Cooley LLP~~To ofthe ~~Palo~~extent ~~Alto~~that we rely on third-party contract manufacturers, ~~California~~which ~~will~~in ~~pass~~some ~~upon~~cases ~~the~~may ~~validity~~be sole sourced, we are exposed to a number of risks, any of which could delay or prevent the ~~securities~~completion ~~offered~~of ~~hereby.~~our ~~The~~preclinical ~~underwriters~~studies ~~are~~or ~~being~~clinical ~~represented by~~trials, ~~McDermott~~or ~~Will &~~the ~~Emery LLP~~regulatory approval or commercialization of ~~New~~our ~~York~~product candidates, ~~New~~result ~~York~~ in ~~connection~~higher ~~with~~costs, or deprive us of potential product revenues in the ~~offering~~future. Some of these risks include, but are not limited to:

● our ~~EXPERTS~~ potential contract manufacturers failing to develop an acceptable formulation to support late-stage clinical trials for, or the commercialization of, our product candidates;

~~The~~● ~~consolidated~~our ~~financial~~potential ~~statements~~contract ofmanufacturers ~~Vaxart, Inc.~~failing asto ofmanufacture ~~December 31,~~our ~~2018~~product ~~and~~candidates ~~2017,~~according ~~and~~to ~~for~~their ~~each~~own ~~of the years in the two year period ended December 31~~standards, ~~2018,~~our ~~have been incorporated by reference herein in reliance upon the report of KPMG LLP~~specifications, ~~independent registered public accounting firm~~cGMP, ~~incorporated~~or byregulatory ~~reference herein~~guidelines, ~~and~~or ~~upon~~otherwise ~~the~~manufacturing ~~authority~~material ~~of said firm as experts in accounting and auditing. The audit report covering the December 31, 2018 consolidated financial statements contains an explanatory paragraph~~ that ~~states~~we ~~that~~or ~~the~~regulatory ~~Company~~authorities ~~has~~deem ~~experienced losses and negative cash flows from operations since its inception, has an accumulated deficit, and has debt obligations which raise substantial doubt about its ability~~ to ~~continue~~be asunsuitable afor ~~going~~our ~~concern.~~clinical ~~The~~trials ~~consolidated~~or ~~financial~~commercial ~~statements do not include any adjustments that might result from the outcome of that uncertainty.~~ use;

~~On February 13,~~● ~~2018,~~our ~~privately-held~~potential ~~Vaxart, Inc.,~~contract ormanufacturers ~~Private~~being ~~Vaxart,~~unable ~~and~~to ~~Aviragen~~increase ~~Therapeutics, Inc., or Aviragen, completed a business combination in accordance with~~ the ~~terms~~scale ~~an agreement and plan~~ of ~~merger~~or ~~and~~the ~~reorganization,~~capacity ~~dated October 27~~for, ~~2017,~~or byreformulate ~~and~~the ~~among~~form ~~Aviragen~~of, ~~Agora~~our ~~Merger~~product ~~Sub~~candidates, ~~Inc.,~~ orwhich ~~Merger~~may ~~Sub,~~cause ~~and~~us ~~Private Vaxart, pursuant~~ to ~~which~~ ~~Merger~~experience ~~Sub merged with and into Private Vaxart, with Private Vaxart surviving as~~ a ~~wholly-owned~~shortage ~~subsidiary~~in ofsupply ~~Aviragen,~~ or ~~the~~cause ~~Merger. Aviragen changed its name at~~ the ~~closing~~cost ~~of the Merger~~ to ~~Vaxart, Inc.,~~ ormanufacture ~~the~~our ~~Combined~~product ~~Company,~~candidates ~~and~~to ~~Private~~increase. ~~Vaxart~~There ~~changed~~can ~~its~~be ~~name~~no toassurance ~~Vaxart~~that ~~Biosciences, Inc.~~our ~~For~~potential ~~accounting~~contract ~~purposes,~~manufacturers ~~Aviragen~~will ~~was~~be ~~deemed~~able to bemanufacture ~~the~~our ~~acquired~~product ~~entity~~candidates inat ~~the Merger,~~a ~~and~~suitable ~~the~~commercial ~~financial~~scale, ~~statements~~or ofthat ~~Private~~we ~~Vaxart~~will ~~became~~be ~~the~~able ~~historical~~to ~~financial~~find ~~statements~~alternative ofmanufacturers ~~the~~acceptable ~~Combined~~to ~~Company~~us ~~following~~that ~~the~~can ~~Merger.~~do so;

~~In connection~~● ~~with~~our ~~the~~potential ~~closing~~contract ofmanufacturers ~~the~~placing ~~Merger~~a onpriority February 13, 2018, the board of directors of Vaxart, Inc. dismissed Ernst & Young LLP as its independent registered public accounting firm, effective immediately. The reports of Ernst & Young LLP on ~~Aviragen Therapeutics, Inc.'s consolidated financial statements for~~ the ~~fiscal~~manufacture ~~years ended June 30, 2017 and 2016 did not contain an adverse opinion or disclaimer~~ of ~~opinion,~~other ~~nor~~customers’ ~~were they qualified~~ or ~~modified~~their asown ~~to uncertainty~~products, ~~audit~~rather ~~scope,~~than orour accounting principles. During the fiscal years ended June 30, 2017 and 2016, and the subsequent interim period through February 13, 2018 there were no: (1) disagreements (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) with Ernst & Young LLP on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedures, which disagreement if not resolved to the satisfaction of Ernst & Young LLP would have caused Ernst & Young LLP to make reference thereto in its reports on the consolidated financial statements for such years, or (2) reportable events (as described in Item 304(a)(1)(v) of Regulation S-K). products;

~~On February 13,~~● ~~2018,~~our ~~the~~potential ~~board~~contract ofmanufacturers ~~directors~~failing ofto ~~Vaxart, Inc.,~~perform ~~in connection with the Merger and the dismissal of Ernst & Young LLP, approved the engagement of KPMG LLP~~ as ~~the~~agreed ~~Combined~~or ~~Company's~~exiting ~~independent~~from ~~registered public accounting firm for~~ the ~~year~~contract ~~ending~~manufacturing ~~December 31,~~business; ~~2017.~~ and

●	our potential contract manufacturers’ plants being closed as a result of regulatory sanctions or a natural disaster.

Manufacturers of pharmaceutical drug products are subject to ongoing periodic inspections by the FDA, the U.S. Drug Enforcement Administration, or DEA, and corresponding state and other foreign agencies to ensure strict compliance with FDA-mandated cGMP, other government regulations and corresponding foreign standards. We do not have control over our third-party contract manufacturers’ compliance with these regulations and standards and accordingly, failure by our third-party manufacturers, or us, to comply with applicable regulations could result in sanctions being imposed on us or our manufacturers, which could significantly and adversely affect our business.

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In the ~~WHERE~~event ~~YOU~~that ~~CAN~~we ~~FIND~~need ~~MORE~~to ~~INFORMATION~~ change a third-party contract manufacturer, our preclinical studies or our clinical trials, and the commercialization of our product candidates could be delayed, adversely affected or terminated, or such a change may result in the need for us to incur significantly higher costs, which could materially harm our business.

WeDue ~~have~~to ~~filed~~various ~~with~~regulatory ~~the~~restrictions ~~SEC~~in athe ~~registration~~U.S. ~~statement~~and onmany ~~Form S-1~~other ~~under~~countries, ~~the~~as ~~Securities~~well ~~Act~~as ~~with~~potential ~~respect~~capacity toconstraints ~~the~~on ~~shares~~manufacturing ofthat ~~common~~occur ~~stock~~from ~~and pre~~time-~~funded~~to-time ~~warrants.~~in ~~This~~our ~~prospectus~~industry, ~~which~~various ~~constitutes~~steps ain ~~part of~~ the ~~registration~~manufacture ~~statement,~~of ~~does~~our ~~not~~product ~~contain~~candidates ~~all~~are ofsole-sourced ~~the~~to ~~information~~certain ~~set~~contract ~~forth~~manufacturers. inIn ~~the~~accordance ~~registration~~with ~~statement~~cGMPs, orchanging ~~the~~manufacturers ~~exhibits~~may ~~filed~~require ~~with~~ the ~~registration~~re-validation ~~statement.~~of ~~For~~manufacturing ~~further~~processes ~~information about us~~ and ~~the~~procedures, ~~common stock~~ and ~~pre-funded~~may ~~warrants~~require ~~offered~~further ~~hereby,~~preclinical westudies ~~refer~~or ~~you~~clinical trials to ~~the~~show ~~registration~~comparability ~~statement~~between ~~and~~ the ~~exhibits~~materials ~~filed~~produced ~~with~~by ~~the registration~~different ~~statement~~manufacturers. ~~Statements~~Changing ~~contained~~a ~~in this prospectus regarding the contents of any~~ contract ormanufacturer ~~any~~may ~~other~~be ~~document~~difficult ~~that~~and iscould ~~filed~~be asextremely ancostly ~~exhibit~~and ~~to the registration statement are not necessarily complete~~time-consuming, ~~and~~which ~~each~~could ~~such~~result ~~statement~~in isour ~~qualified~~inability into ~~all~~manufacture ~~respects~~our byproduct ~~reference~~candidates tofor ~~the~~an ~~full~~extended ~~text~~period of ~~such~~time ~~contract~~and ora ~~other~~delay, ~~document~~as ~~filed~~well as an ~~exhibit~~increase toin costs, in the ~~registration~~development ~~statement.~~of our product candidates.

We ~~are~~ ~~subject~~may tonot ~~the~~be ~~information~~able ~~and~~to ~~reporting~~manufacture ~~requirements~~our ofproduct ~~the~~candidates ~~Exchange Act and,~~ in ~~accordance~~sufficient ~~with~~quantities ~~this law, are required~~ to ~~file~~commercialize ~~periodic reports, proxy statements and other information with the SEC~~them. ~~You can read our SEC filings, including the registration statement, over the internet at the SEC's website at www.sec.gov.~~

~~We make~~In ~~available~~order ~~free~~to receive FDA approval of ~~charge~~our product candidates, onwe orwill ~~through~~need ~~the~~to ~~investor~~manufacture ~~relations~~such ~~section~~product ofcandidates in larger quantities. We may not be able to successfully increase the manufacturing capacity for our ~~website~~product candidates in a timely or economic manner, ~~annual~~or ~~reports~~at onall. ~~Form 10-K~~In the event FDA approval is received, ~~quarterly~~we ~~reports~~will onneed ~~Form 10~~to increase production of our product candidates. Significant scale-Qup of manufacturing may require additional validation studies, ~~current~~which ~~reports on~~the ~~Form 8-K~~FDA must review and ~~amendments~~approve. If we are unable to ~~those~~successfully ~~reports~~increase ~~filed~~the ormanufacturing ~~furnished~~capacity ~~pursuant~~for toour ~~Section 13(a)~~product orcandidates, ~~15(d)~~the ofclinical trials, the ~~Exchange~~regulatory ~~Act~~approval asand ~~soon~~the ascommercial ~~reasonably~~launch ~~practicable~~of ~~after~~our weproduct ~~electronically~~candidates ~~file~~may ~~such material~~be ~~with~~delayed, or ~~furnish~~there itmay tobe a shortage in supply. Our product candidates require precise, ~~the~~high-quality ~~SEC~~manufacturing. ~~The~~Failure ~~information~~to ~~found~~achieve onand ~~our~~maintain ~~website~~high-quality manufacturing, ~~www.vaxart.com~~including the incidence of manufacturing errors, ~~other~~could ~~than~~result asin ~~specifically~~patient ~~incorporated~~injury byor ~~reference~~death, delays or failures in ~~this~~ ~~prospectus~~testing or delivery, iscost ~~not~~overruns ~~part~~or ofother ~~this~~problems ~~prospectus.~~that could harm our business, financial condition and results of operations.

The manufacture of pharmaceutical products in compliance with cGMP regulations requires significant expertise and capital investment, including the development of advanced manufacturing techniques and process controls.

Manufacturers of pharmaceutical products often encounter difficulties in production, including difficulties with production costs and yields, quality control, including stability of the product candidates and quality assurance testing, or shortages of qualified personnel. If we were to encounter any of these difficulties or otherwise fail to comply with our obligations under applicable regulations, our ability to provide study materials in our clinical trials would be jeopardized. Any delay or interruption in the supply of clinical trial materials could delay the completion of our clinical trials, increase the costs associated with maintaining our clinical trial programs and, depending upon the period of delay, require us to commence new trials at significant additional expense or to terminate the studies and trials completely.

We must comply with cGMP requirements enforced by the FDA through its facilities inspection program. These requirements include, among other things, quality control, quality assurance and the maintenance of records and documentation. Manufacturers of our component materials may be unable to comply with these cGMP requirements and with other FDA, state and foreign regulatory requirements. The FDA or similar foreign regulatory agencies at any time may also implement new standards, or change their interpretation and enforcement of existing standards, for manufacture, packaging or testing of products. We have little control over our manufacturers’ compliance with these regulations and standards. A failure to comply with these requirements may result in fines and civil penalties, suspension of production, suspension or delay in product approval, product seizure or recall, or withdrawal of product approval. If the safety of any product supplied is compromised due to our failure, or that our third-party manufacturers, to adhere to applicable laws or for other reasons, we may not be able to obtain regulatory approval for or successfully commercialize our products, and we may be held liable for any injuries sustained as a result. Any of these factors could cause a delay of clinical trials, regulatory submissions, approvals or commercialization of any product candidates we may develop or acquire in the future, or entail higher costs, or impair our reputation.

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We currently ~~INCORPORATION~~rely OFon ~~CERTAIN~~single ~~INFORMATION~~source BYvendors ~~REFERENCE~~ for key tablet vaccine components and certain strains needed in our tablet vaccine candidates, which could impair our ability to manufacture and supply our tablet vaccine candidates.

~~The~~We ~~SEC~~currently ~~allows~~depend uson tosingle ~~"incorporate~~source byvendors ~~reference"~~for ~~information~~certain ~~from~~raw ~~other~~materials ~~documents~~used ~~that~~in wethe ~~file~~manufacture ~~with~~of ~~it,~~our ~~which~~tablet ~~means~~vaccine ~~that~~candidates. weAny ~~can~~production ~~disclose important~~shortfall ~~information~~that toimpairs ~~you~~the bysupply ~~referring~~of ~~you~~the torelevant ~~those~~raw ~~documents.~~materials ~~The~~could ~~information~~have ~~incorporated~~a bymaterial ~~reference~~adverse iseffect ~~considered~~on toour bebusiness, ~~part of~~financial ~~this~~condition ~~prospectus.~~and ~~Information~~results inof ~~this~~operations. ~~prospectus~~An ~~supersedes~~inability ~~information~~to ~~incorporated~~continue ~~by reference that we filed with the SEC prior~~ to ~~the~~source ~~date~~product offrom ~~this~~these ~~prospectus~~suppliers, ~~while~~which ~~information~~could ~~that~~be wedue ~~file later~~to ~~with~~regulatory ~~the~~actions ~~SEC~~or ~~will~~requirements ~~automatically~~affecting ~~update~~the ~~and~~supplier, ~~supersede~~adverse ~~the~~financial ~~information~~or inother ~~this~~strategic ~~prospectus.~~developments Weexperienced ~~incorporate~~ by ~~reference~~a ~~into~~supplier, ~~this~~labor ~~prospectus~~disputes ~~and~~or ~~the~~shortages, ~~registration~~unexpected ~~statement~~demands ofor ~~which~~quality ~~this~~issues, ~~prospectus is~~could amaterially ~~part~~adversely ~~the~~affect ~~information~~our operating results or ~~documents~~our ~~listed~~ability ~~below~~to ~~that~~conduct weclinical ~~have~~trials, ~~filed~~either ~~with~~of ~~the~~which ~~SEC~~could ~~(Commission~~significantly ~~File~~harm Noour business. ~~001-35285):~~

We ~~also~~ ~~incorporate~~rely byon ~~reference~~CROs ~~any future filings (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K~~ and ~~exhibits~~clinical ~~filed~~trial onsites ~~such form that are related~~ to ~~such~~ensure ~~items unless such Form 8-K expressly provides to~~ the ~~contrary)~~proper ~~made~~and ~~with~~timely ~~the~~conduct ~~SEC pursuant to Sections 13(a), 13(c), 14 or 15(d)~~ of ~~the~~our ~~Exchange~~clinical ~~Act~~trials, ~~until the termination of the offering of the shares of our common stock made by this prospectus~~ and will become a part of this prospectus from the date that such documents are filed with the SEC. Information in such future filings updates and supplements the information provided in this prospectus. Any statements in any such future filings will automatically be deemed to modify and supersede any information in any document we ~~previously~~expect ~~filed with the SEC that is incorporated or deemed~~ to behave ~~incorporated~~limited ~~herein~~influence byover ~~reference~~their toactual ~~the extent that statements in the later filed document modify or replace such earlier statements~~performance.

~~You can~~We ~~request~~also arely ~~copy~~on CROs to monitor and manage data for our clinical programs, as well as the execution of ~~these~~future ~~filings~~nonclinical studies. We expect to control only certain aspects of our CROs’ activities. Nevertheless, atwe nowill ~~cost~~be responsible for ensuring that each of our studies is conducted in accordance with the applicable protocol, bylegal, ~~writing~~regulatory orand ~~telephoning~~scientific usstandards atand our reliance on the ~~following~~CROs ~~address~~does ornot ~~telephone~~relieve ~~number:~~us of these regulatory responsibilities.

~~Vaxart~~We and our CROs are required to comply with the Good Laboratory Practice and GCP, ~~Inc~~ which are regulations and guidelines enforced by the FDA and are also required by the Competent Authorities of the Member States of the European Economic Area and comparable foreign regulatory authorities in the form of International Conference on Harmonization guidelines for any of our product candidates that are in preclinical and clinical development. ~~290~~ ~~Utah~~The ~~Ave Suite 200 South~~Regulatory ~~San~~authorities ~~Francisco~~enforce GCP through periodic inspections of trial sponsors, ~~California~~principal ~~94080 Attn:~~investigators ~~Secretary (650) 550-3500~~and clinical trial sites. If we or our CROs fail to comply with GCPs, the clinical data generated in our clinical trials may be deemed unreliable and the FDA or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. Accordingly, if our CROs fail to comply with these regulations or fail to recruit enough subjects, we may be required to repeat clinical trials, which would delay the regulatory approval process.

~~Copies of~~Our ~~these~~CROs ~~filings~~ are not our employees, and we cannot control whether they devote sufficient time and resources to our clinical and nonclinical programs. These CROs may also ~~available~~have ~~through~~relationships with other commercial entities, including our competitors, for whom they may also be conducting clinical trials, or other drug development activities which could harm our competitive position. We face the ~~"Investor"~~risk ~~section~~of potential unauthorized disclosure or misappropriation of our ~~website~~intellectual atproperty ~~www~~by CROs, which may reduce our trade secret protection and allow our potential competitors to access and exploit our proprietary technology.~~vaxart.com.~~ ~~For~~If ~~other~~our ~~ways~~CROs do not successfully carry out their contractual duties or obligations, fail to ~~obtain~~meet ~~a copy~~expected deadlines, or if the quality or accuracy of ~~these~~the ~~filings~~clinical data they obtain is compromised due to the failure to adhere to our clinical protocols or regulatory requirements or for any other reasons, ~~please~~our ~~refer~~clinical trials may be extended, delayed or terminated, and we may not be able to ~~"Where~~obtain ~~You~~regulatory ~~Can~~approval ~~Find~~for, ~~More~~or ~~Information"~~successfully ~~above~~commercialize, any product candidate that we develop. As a result, our financial results and the commercial prospects for any product candidate that we develop would be harmed, our costs could increase, and our ability to generate significant revenues could be delayed.

~~Any information~~If inour ~~any~~relationships ofwith ~~the~~these ~~foregoing~~CROs ~~documents~~terminate, ~~will~~we ~~automatically~~may not be ~~deemed~~able to beenter ~~modified~~into arrangements with alternative CROs or ~~superseded~~do so on commercially reasonable terms. Switching or adding additional CROs involves substantial costs and requires management time and focus. In addition, there is a natural transition period when a new CRO commences work. As a result, delays occur, which can materially impact our ability to ~~the~~meet ~~extent~~our desired clinical development timelines. While we endeavor to carefully manage our relationships with our CROs, there can be no assurance that ~~information~~we will not encounter challenges or delays in ~~this~~the ~~prospectus~~future ~~modifies~~or that these delays or ~~replaces~~challenges ~~such information.~~will not have an adverse impact on our business, financial condition and prospects.

We may seek to selectively establish collaborations and, if we are unable to establish them on commercially reasonable terms, we may have to alter our development and commercialization plans.

Our product development programs and the potential commercialization of our product candidates will require substantial additional cash to fund expenses. For some of our product candidates, including our seasonable influenza tablet, we may decide to collaborate with governmental entities or additional pharmaceutical and biotechnology companies for the development and potential commercialization of those product candidates.

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~~Shares~~We face significant competition in seeking appropriate collaborators. Whether we reach a definitive agreement for a collaboration will depend, among other things, upon our assessment of ~~Common~~the ~~Stock~~ collaborator’s resources and expertise, the terms and conditions of the proposed collaboration and the proposed collaborator’s evaluation of a number of factors. Those factors may include the design or results of clinical trials, the likelihood of approval by the FDA or similar regulatory authorities outside the U.S., the potential market for the subject product candidate, the costs and complexities of manufacturing and delivering such product candidate to patients, the potential of competing products, the existence of uncertainty with respect to our ownership of technology, which can exist if there is a challenge to such ownership without regard to the merits of the challenge and industry and market conditions generally. The collaborator may also consider alternative product candidates for similar indications that may be available to collaborate on and whether such a collaboration could be more attractive than the one with us for our product candidate.

Our ~~Pre~~relationships with customers and third-~~Funded~~party ~~Warrants~~payors will be subject to ~~Purchase~~applicable ~~Shares~~anti-kickback, offraud ~~Common~~and ~~Stock~~ abuse and other healthcare laws and regulations, which could expose us to criminal sanctions, civil penalties, contractual damages, reputational harm and diminished profits and future earnings.

Healthcare ~~Common~~providers, ~~Warrants~~physicians toand ~~Purchase Shares~~third-party payors play a primary role in the recommendation and prescription of ~~Common~~any ~~Stock~~ product candidates for which we obtain marketing approval. Our future arrangements with third-party payors and customers may expose us to broadly applicable fraud and abuse and other healthcare laws and regulations that may constrain the business or financial arrangements and relationships through which we market, sell and distribute our medicines for which we obtain marketing approval. Restrictions under applicable federal and state healthcare laws and regulations include the following:

~~Prospectus~~ ● the federal Anti-Kickback Statute prohibits, among other things, persons from knowingly and willfully soliciting, offering, receiving or providing remuneration, directly or indirectly, in cash or in kind, to induce or reward either the referral of an individual for, or the purchase, order or recommendation of, any good or service, for which payment may be made under federal and state healthcare programs such as Medicare and Medicaid;

~~Sole~~● ~~Book-Running~~the ~~Manager~~ federal FCA imposes criminal and civil penalties, including civil whistleblower or qui tam actions, against individuals or entities for knowingly presenting, or causing to be presented, to the federal government, claims for payment that are false or fraudulent or making a false statement to avoid, decrease or conceal an obligation to pay money to the federal government;

~~H.C.~~● ~~Wainwright & Co.~~ the federal HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act, imposes criminal and civil liability for executing a scheme to defraud any healthcare benefit program and imposes obligations, including mandatory contractual terms, with respect to safeguarding the privacy, security and transmission of individually identifiable health information;

~~Manager~~ ● the federal false statements statute prohibits knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false statement in connection with the delivery of or payment for healthcare benefits, items or services;

~~Brookline~~● ~~Capital~~the ~~Markets~~ federal transparency requirements under the Affordable Care Act requires manufacturers of drugs, devices, biologics and medical supplies to report to the Department of Health and Human Services information related to physician payments and other transfers of value and physician ownership and investment interests; and

~~, 2019~~ 46

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● analogous ~~PART~~state ~~II—INFORMATION~~laws ~~NOT~~and ~~REQUIRED~~regulations, INsuch ~~PROSPECTUS~~ as state anti-kickback and false claims laws, may apply to sales or marketing arrangements and claims involving healthcare items or services reimbursed by non-governmental third-party payors, including private insurers, and some state laws require pharmaceutical companies to comply with the pharmaceutical industry’s voluntary compliance guidelines and the relevant compliance guidance promulgated by the federal government in addition to requiring vaccine manufacturers to report information related to payments to physicians and other health care providers or marketing expenditures.

We ~~ITEM~~may ~~13. OTHER~~not ~~EXPENSES~~be OFsuccessful ~~ISSUANCE~~in ~~AND~~establishing ~~DISTRIBUTION~~ and maintaining additional strategic partnerships, which could adversely affect our ability to develop and commercialize products, negatively impacting our operating results.

~~The~~We ~~following~~continue ~~table~~to ~~sets~~strategically ~~forth~~evaluate anour ~~estimate~~partnerships ofand, as appropriate, we expect to enter into additional strategic partnerships in the ~~fees~~future, including potentially with major biotechnology or biopharmaceutical companies. We face significant competition in seeking appropriate partners for our product candidates, and ~~expenses~~the negotiation process is time-consuming and complex. In order for us to successfully partner our product candidates, ~~other~~potential ~~than~~partners ~~underwriting~~must ~~discounts~~view these product candidates as economically valuable in markets they determine to be attractive in light of the terms that we are seeking and ~~commissions~~other ~~payable~~available products for licensing by usother companies. Even if we are successful in ~~connection~~ ~~with~~our efforts to establish strategic partnerships, the ~~issuance~~terms that we agree upon may not be favorable to us, and ~~distribution~~we may not be able to maintain such strategic partnerships if, for example, development or approval of ~~the~~a ~~securities~~product ~~being~~candidate ~~registered~~is delayed or sales of an approved product are disappointing. ~~All~~Any delay in entering into strategic partnership agreements related to our product candidates could delay the ~~amounts~~development ~~shown~~and commercialization of such candidates and reduce their competitiveness even if they reach the market. If we are ~~estimates,~~not ~~except~~able ~~for~~to generate revenue under our strategic partnerships when and in accordance with our expectations or the ~~SEC~~expectations ~~registration~~of ~~fee~~industry analysts, this failure could harm our business and have an immediate adverse effect on the ~~FINRA~~trading ~~filing~~price ~~fee.~~of our common stock.

	Amount
SEC registration fee	$	1,394
FINRA filing fee		2,225
Accounting fees and expenses		80,000
Legal fees and expenses		150,000
Transfer agent and registrar fees		15,000
Printing fees		75,000
Miscellaneous expenses		76,381

Total	$	400,000

If we fail to establish and maintain additional strategic partnerships related to our unpartnered product candidates, we will bear all the risks and costs related to the development of any such product candidate, and we may need to seek additional financing, hire additional employees and otherwise develop expertise, such as regulatory expertise, for which we have not budgeted. If we were not successful in seeking additional financing, hiring additional employees or developing additional expertise, our cash burn rate would increase or we would need to take steps to reduce our rate of product candidate development. This could negatively affect the development of any unpartnered product candidate.

Strategic ~~ITEM~~partnerships ~~14. INDEMNIFICATION~~or OFacquisitions ~~DIRECTORS~~we ~~AND~~have ~~OFFICERS~~ made or may make could turn out to be unsuccessful.

~~Section 145~~As part of ~~the~~our ~~Delaware~~strategy, ~~General~~we ~~Corporation~~monitor ~~Law~~and ~~authorizes~~analyze astrategic ~~court~~partnership toor ~~award,~~acquisition oropportunities athat ~~corporation's~~we ~~board~~believe ofwill ~~directors~~create tovalue ~~grant~~for our stockholders. We may acquire companies, ~~indemnity~~ tobusinesses, ~~directors~~products and ~~officers~~technologies inthat ~~terms~~complement ~~sufficiently~~or ~~broad~~augment toour ~~permit~~existing business; however, such ~~indemnification~~acquisitions ~~under~~could ~~certain~~involve ~~circumstances~~numerous ~~for~~risks ~~liabilities,~~that ~~including~~may ~~reimbursement~~prevent ~~for~~us ~~expenses~~from ~~incurred,~~fully ~~arising~~realizing ~~under~~ the ~~Securities~~benefits ~~Act~~that ofwe ~~1933,~~anticipated as ~~amended,~~a orresult ~~the~~of ~~Securities~~such ~~Act~~transactions.

~~Our amended~~We ~~and~~may ~~restated~~not ~~certificate~~be ofable ~~incorporation~~to ~~provide~~integrate ~~for~~any ~~indemnification~~acquired ofbusiness ~~our~~successfully ~~directors,~~or ~~officers~~operate any acquired business profitably. In addition, ~~employees~~integrating ~~and~~any ~~other~~newly ~~agents~~acquired tobusiness ~~the~~could ~~maximum~~be ~~extent~~expensive ~~permitted~~and bytime-consuming, ~~the~~place ~~Delaware General~~a ~~Corporation~~significant ~~Law~~strain on managerial, operational and ~~our~~financial ~~amended~~resources and ~~restated~~could ~~bylaws~~prove ~~require~~to usbe tomore ~~indemnify~~difficult ~~our~~or ~~directors,~~expensive ~~officers,~~than ~~employees,~~we ~~and~~predict. ~~other~~The ~~agents~~diversion toof ~~the~~our ~~maximum~~management's ~~extent~~attention ~~permitted~~and byany ~~the~~delay ~~Delaware~~or ~~General Corporation~~difficulties ~~Law.~~encountered ~~However,~~in ~~Delaware~~connection ~~law~~with ~~prohibits~~any ~~the~~future ~~Registrant's~~acquisitions ~~certificate~~we ofmay ~~incorporation~~consummate ~~from~~could ~~limiting~~result in the ~~liability~~disruption of ~~the~~our ~~Registrant's~~ongoing ~~directors~~business ~~for~~or ~~the following:~~inconsistencies in standards and controls that could negatively affect our ability to maintain third-party relationships.

We ~~have~~ ~~entered~~may fail to derive any commercial value from the acquired technology, products and ~~expect~~intellectual toproperty, ~~continue~~including as a result of the failure to ~~enter~~obtain ~~into~~regulatory ~~agreements~~approval or to ~~indemnify~~monetize ~~our~~products ~~directors~~once approved, as well as risks from lengthy product development and ~~executive~~high ~~officers~~upfront development costs without guarantee of successful results. ~~With~~Patents ~~certain~~and ~~exceptions~~other intellectual property rights covering acquired technology and/or intellectual property may not be obtained, ~~these~~and ~~agreements~~if ~~provide~~obtained, ~~for~~may ~~indemnification for~~not ~~related~~be ~~expenses~~sufficient to fully protect the technology or intellectual property. We may also be subject to liabilities, including unanticipated litigation costs, ~~among~~that ~~other~~are ~~things~~not covered by indemnification protection we may obtain. As we pursue strategic transactions, ~~attorneys'~~we ~~fees~~may value the acquired company or partner incorrectly, ~~judgments~~fail to successfully manage our operations as our asset diversity increases, ~~fines~~expend ~~and~~unforeseen ~~settlement~~costs ~~amounts~~during ~~incurred~~the byacquisition ~~any~~or ofintegration ~~these~~process, ~~individuals~~or inencounter ~~any~~other ~~action~~unanticipated risks or ~~proceeding~~challenges. AtWe ~~present,~~may ~~there~~fail isto ~~no pending~~value ~~litigation~~a partnership or ~~proceeding~~acquisition ~~involving~~accurately, ~~any~~properly ofaccount for it in our ~~directors,~~consolidated ~~officers~~financial statements, or ~~employees~~successfully ~~for~~divest ~~which~~it ~~indemnification~~or isotherwise ~~sought~~realize ~~and~~the wevalue ~~are~~which ~~not~~we ~~aware~~originally ofanticipated ~~any~~or ~~threatened~~have ~~litigation~~subsequently ~~that~~reflected ~~may~~in ~~result~~our inconsolidated ~~claims for~~financial ~~indemnification~~statements.

We ~~maintain insurance policies that indemnify our directors and officers against various liabilities arising under the Securities Act and the Exchange Act that might be incurred by any~~ 47 ~~director or officer in his capacity as such.~~

II-1

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~~The Underwriting~~Moreover, ~~Agreement~~we ~~filed~~may asneed ~~Exhibit 1.1~~ to ~~this~~raise ~~Registration~~additional ~~Statement~~funds ~~provides~~through ~~for~~public ~~indemnification~~or byprivate ~~the~~debt ~~underwriters~~or ofequity usfinancing, ~~and~~or ~~our~~issue ~~directors~~additional ~~and~~shares, ~~officers~~to ~~for~~acquire ~~certain liabilities~~any ~~under~~businesses ~~the~~or ~~Securities Act~~products, which may result in dilution for stockholders or ~~otherwise.~~the incurrence of indebtedness.

~~Insofar as~~Any ~~indemnification~~failure ~~for~~by ~~liabilities~~us ~~arising~~to ~~under~~effectively ~~the~~limit ~~Securities~~such ~~Act~~risks ~~may~~as bewe ~~permitted~~implement ~~for~~our ~~directors,~~strategic ~~executive~~partnership ~~officers~~ or ~~persons~~acquisitions ~~controlling~~could ~~us,~~have wea ~~have~~material ~~been~~adverse ~~informed~~effect ~~that~~on ~~in the~~our ~~opinion~~business, offinancial ~~the~~condition ~~SEC~~or ~~such~~results ~~indemnification~~of isoperations ~~against~~and ~~public~~may ~~policy~~negatively asimpact ~~expressed~~our innet income and cause the ~~Securities~~price ~~Act~~of ~~and~~our issecurities ~~therefore~~to ~~unenforceable~~fall.

In ~~ITEM~~the ~~15. RECENT~~event ~~SALES~~that OFa ~~UNREGISTERED~~third-party ~~SECURITIES~~ contract manufacturer cannot timely supply sufficient bulk vaccine to allow us to manufacture our vaccine tablets, our preclinical studies or our clinical trials and the commercialization of our product candidates could be delayed, adversely affected or terminated, or may result in the need for us to incur significantly higher costs, which could materially harm our business.

~~None~~Due to various regulatory restrictions in the U. S. and many other countries, as well as potential capacity constraints on manufacturing that occur from time-to-time in our industry, various steps in the manufacture of our product candidates are sole-sourced to certain contract manufacturers. In accordance with cGMP, changing manufacturers may require the re-validation of manufacturing processes and procedures, and may require further preclinical studies or clinical trials to show comparability between the materials produced by different manufacturers. Changing a contract manufacturer may be difficult and could be extremely costly and time-consuming, which could result in our inability to manufacture our product candidates for an extended period and a delay in the development of our product candidates. Further, in order to maintain our development timelines in the event of a change in a third-party contract manufacturer, we may incur significantly higher costs to manufacture our product candidates.

If ~~ITEM~~third-party ~~16. EXHIBITS~~vendors, ~~AND~~upon ~~FINANCIAL~~whom ~~STATEMENT~~we ~~SCHEDULES~~ rely to conduct our preclinical studies or clinical trials, do not perform or fail to comply with strict regulations, these studies or trials may be delayed, terminated, or fail, or we could incur significant additional expenses, which could materially harm our business.

			Incorporated by Reference
Exhibit Number		Description	Schedule/ Form	File Number	Exhibit		File Date
	1.1*	Underwriting Agreement
	2.1	Agreement and Plan of Merger and Reorganization, dated October 27, 2017, by and among Aviragen Therapeutics, Inc., Vaxart, Inc. and Agora Merger Sub, Inc.	8-K	001-35285		2.1	October 30, 2017
	2.2	Amendment No. 1, dated as of February 7, 2018, to the Agreement and Plan of Merger and Reorganization, dated October 27, 2017, by and among Aviragen Therapeutics, Inc., Vaxart, Inc. and Agora Merger Sub, Inc.	8-K	001-35285		2.1	February 7, 2018
	3.1	Restated Certificate of Incorporation of Aviragen Therapeutics, Inc.	10-K	001-35285		3.1	September 13, 2016
	3.2	Certificate of Amendment to Restated Certificate of Incorporation of Aviragen Therapeutics, Inc.	8-K	001-35285		3.1	February 20, 2018
	3.3	Certificate of Amendment to Restated Certificate of Incorporation of Vaxart, Inc.	8-K	001-35285		3.2	February 20, 2018
	3.4	Certificate of Amendment to Restated Certificate of Incorporation of Vaxart, Inc.	8-K	001-35285		3.1	April 24, 2019
	3.5	Restated By-laws of Aviragen Therapeutics, Inc.	10-K	001-35285		3.2	September 13, 2016

We have limited resources dedicated to designing, conducting and managing our preclinical studies and clinical trials. We have historically relied on, and intend to continue to rely on, third parties, including clinical research organizations, consultants and principal investigators, to assist us in designing, managing, conducting, monitoring and analyzing the data from our preclinical studies and clinical trials. We rely on these vendors and individuals to perform many facets of the clinical development process on our behalf, including conducting preclinical studies, the recruitment of sites and patients for participation in our clinical trials, maintenance of good relations with the clinical sites, and ensuring that these sites are conducting our trials in compliance with the trial protocol and applicable regulations. If these third parties fail to perform satisfactorily, or do not adequately fulfill their obligations under the terms of our agreements with them, we may not be able to enter into alternative arrangements without undue delay or additional expenditures, and therefore the preclinical studies and clinical trials of our product candidates may be delayed or prove unsuccessful.

IIFurther, the FDA, or similar regulatory authorities in other countries, may inspect some of the clinical sites participating in our clinical trials or our third-2party vendors’ sites to determine if our clinical trials are being conducted according to GCP or similar regulations. If we, or a regulatory authority, determine that our third-party vendors are not in compliance with, or have not conducted our clinical trials according to, applicable regulations, we may be forced to exclude certain data from the results of the trial, or delay, repeat or terminate such clinical trials.

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			Incorporated by Reference
Exhibit Number		Description	Schedule/ Form	File Number	Exhibit		File Date
	4.1	Reference is made to Exhibits 3.1 to 3.5.
	4.2	Specimen Common Stock Certificate	S-3	333-228910		4.2	December 20, 2018
	4.3	Form of Pre-Funded Warrant
	4.4	Form of Common Warrant
	4.5	Form of Representative Warrant
	5.1*	Opinion of Cooley LLP
	10.1+	Collaboration and License Agreement dated September 29, 2003, between Biota Holdings Limited and Sankyo Co., Ltd.	10-Q	001-35285		10.5	May 10, 2013
	10.2+	Amendment #1 to Collaboration and License Agreement dated June 30, 2005, between Biota Holdings Limited, Biota Scientific Management Pty. Ltd. and Sankyo Company, Ltd.	10-Q	001-35285		10.6	May 10, 2013
	10.3	Amendment #2 to Collaboration and License Agreement, dated March 27, 2009, between Biota Holdings Limited, Biota Scientific Management Pty. Ltd. and Daiichi Sankyo Company, Limited	10-Q	001-35285		10.7	May 10, 2013
	10.4+	Commercialization Agreement dated March 27, 2009, between Biota Holdings Limited, Biota Scientific Management Pty. Ltd and Daiichi Sankyo Company, Ltd.	10-Q	001-35285		10.8	May 10, 2013
	10.5+	Contract dated March 31, 2011, between Biota Scientific Management Pty. Ltd. and Office of Biomedical Advanced Research and Development Authority within the Office of the Assistant Secretary for preparedness and Response at the U.S. Department of Health and Human Services	10-Q	001-35285		10.9	May 10, 2013

Risks Related to Intellectual Property

~~II-3~~If we are unable to obtain and maintain patent protection for our oral vaccine platform technology and product candidates or if the scope of the patent protection obtained is not sufficiently broad, we may not be able to compete effectively in our markets.

Our success depends in large part on our ability to obtain and maintain patent protection in the U.S. and other countries. We seek to protect our proprietary position by filing patent applications in the U.S. and abroad related to our development programs and product candidates. The patent prosecution process is expensive and time-consuming, and we may not be able to file and prosecute all necessary or desirable patent applications, or maintain and enforce any patents that may issue from such patent applications, at a reasonable cost or in a timely manner.

It is also possible that we will fail to identify patentable aspects of our research and development output before it is too late to obtain patent protection. The patent applications that we own may fail to result in issued patents with claims that cover any of our product candidates in the U.S. or in other countries. There is no assurance that the entire potentially relevant prior art relating to our patents and patent applications has been found, which can invalidate a patent or prevent a patent from issuing from a pending patent application. Even if patents do successfully issue, third parties may challenge their validity, enforceability or scope, which may result in such patents being narrowed, invalidated, or held unenforceable. Any successful challenge to these patents or any other patents owned by or licensed to us could deprive us of rights necessary for the successful commercialization of any product candidates or companion diagnostic that we may develop. Further, if we encounter delays in regulatory approvals, the period of time during which we could market a product candidate and companion diagnostic under patent protection could be reduced.

If the patent applications we hold with respect to our platform technology and product candidates fail to issue, if their breadth or strength of protection is threatened, or if they fail to provide meaningful exclusivity for our product candidates, it could dissuade companies from collaborating with us to develop product candidates and threaten our ability to commercialize future drugs. Any such outcome could harm our business.

The patent position of biotechnology and pharmaceutical companies generally is highly uncertain, involves complex legal and factual questions and has in recent years been the subject of much litigation. In addition, the laws of foreign countries may not protect our rights to the same extent as the laws of the U.S. For example, European patent law restricts the patentability of methods of treatment of the human body more than U.S. law does. Publications of discoveries in scientific literature often lag behind the actual discoveries, and patent applications in the U.S. and other jurisdictions are typically not published until 18 months after filing, or in some cases not at all. Therefore, we cannot know with certainty whether we were the first to make the inventions claimed in our owned or licensed patents or pending patent applications, or that we were the first to file for patent protection of such inventions. As a result, the issuance, scope, validity, enforceability and commercial value of our patent rights are highly uncertain. Our pending and future patent applications may not result in patents being issued which protect our technology or product candidates, in whole or in part, or which effectively prevent others from commercializing competitive technologies and vaccines. Even if our patent applications issue as patents, they may not issue in a form that will provide us with any meaningful protection, prevent competitors from competing with us or otherwise provide us with any competitive advantage. Our competitors may be able to circumvent our patents by developing similar or alternative product candidates in a non-infringing manner. Changes in either the patent laws or interpretation of the patent laws in the U.S. and other countries may diminish the value of our patents or narrow the scope of our patent protection.

Recent patent reform legislation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents. On September 16, 2011, the Leahy-Smith America Invents Act (the “Leahy-Smith Act”) was signed into law. The Leahy-Smith Act includes several significant changes to U.S. patent law. These include provisions that affect the way patent applications are prosecuted and may also affect patent litigation. The U.S. Patent Office recently developed new regulations and procedures to govern administration of the Leahy-Smith Act, and many of the substantive changes to patent law associated with the Leahy-Smith Act, notably, the first to file provisions, only became effective on March 16, 2013. Accordingly, it is not clear what, if any, impact the Leahy-Smith Act will have on the operation of our business. However, the Leahy-Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, all of which could have an adverse effect on our business and financial condition.

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			Incorporated by Reference
Exhibit Number		Description	Schedule/ Form	File Number	Exhibit		File Date
	10.6	Research and License Agreement dated February 21, 1990, by and among Biota Scientific Management Pty. Ltd., Biota Holdings Limited, Glaxo Australia Pty. Ltd. and Glaxo Group Limited	10-K	001-35285		10.6	September 27, 2013
	10.7#	2007 Omnibus Equity and Incentive Plan (included as Appendix A to the proxy statement)	DEF 14A	000-04829		—	April 12, 2007
	10.8#	Form of Employee Stock Option Agreement under the 2007 Omnibus Equity and Incentive Plan	8-K	001-35285		10.1	December 10, 2013
	10.9+	Royalty Interest Acquisition Agreement by and between Aviragen Therapeutics, Inc., Biota Holdings Pty Ltd, Biota Scientific Management Pty. Ltd. and HealthCare Royalty Partners III, L.P. dated April 22, 2016	8-K	001-35285		10.1	April 26, 2016
	10.10	Protective Rights Agreement between Aviragen Therapeutics, Inc. and HealthCare Royalty Partners III, L.P. dated April 22, 2016	8-K	001-35285		10.2	April 26, 2016
	10.11#	Form of Employee Stock Option Agreement under the 2016 Equity Incentive Plan	10-Q	001-35285		10.1	May 8, 2017
	10.12#	2016 Equity Incentive Plan (included as Appendix A to the proxy statement)	DEF 14A	001-35285		—	September 27, 2016
	10.13#	Director Stock Option Agreement	S-4	333-222009		10.22	December 12, 2017
	10.14	Form of Indemnification Agreement by and between Vaxart, Inc. and its Directors and Executive Officers	8-K	001-35285		10.3	February 20, 2018

Moreover, we may be subject to a third-party pre-issuance submission of prior art to the U.S. Patent and Trademark Office (“USPTO”) or become involved in derivation, reexamination, inter partes review, post-grant review or interference proceedings challenging our patent rights or the patent rights of others. In other countries, we may be subject to or become involved in opposition proceedings challenging our patent rights or the patent rights of others. An adverse determination in any such submission or proceeding could reduce the scope of, or invalidate, our patent rights, allow third parties to commercialize our technology or product candidates and compete directly with us, without payment to us, or result in our inability to manufacture or commercialize product candidates without infringing third-party patent rights. In addition, if the breadth or strength of protection provided by our patents and patent applications is threatened, it could dissuade companies from collaborating with us to license, develop or commercialize current or future product candidates.

~~II-4~~The issuance of a patent is not conclusive as to its inventorship, scope, validity or enforceability, and our owned and licensed patents may be challenged in the courts or patent offices in the U.S. and abroad. Such challenges may result in patent claims being narrowed, invalidated or held unenforceable, in whole or in part, which could limit our ability to stop others from using or commercializing similar or identical technology and tablet vaccines, or limit the duration of the patent protection of our technology and product candidates. Moreover, patents have a limited lifespan. In the U.S. and other countries, the natural expiration of a patent is generally 20 years after it is filed. Various extensions may be available, however, the life of a patent, and the protection it affords, is limited. Without patent protection for our current or future tablet vaccine candidates, we may be open to competition from generic versions of such product candidates. Given the amount of time required for the development, testing and regulatory review of new product candidates, patents protecting such candidates might expire before or shortly after such candidates are commercialized. As a result, our owned and licensed patent portfolio may not provide us with sufficient rights to exclude others from commercializing product candidates similar or identical to ours.

We may be involved in lawsuits to protect or enforce our patents, the patents of our licensors or our other intellectual property rights, which could be expensive, time consuming and unsuccessful.

Competitors may infringe or otherwise violate our patents, the patents of our licensors or our other intellectual property rights. To counter infringement or unauthorized use, we may be required to file legal claims, which can be expensive and time-consuming. In addition, in an infringement proceeding, a court may decide that a patent of ours or our licensors is not valid, or is unenforceable, or may refuse to stop the other party from using the technology at issue on the grounds that such patents do not cover the technology in question. An adverse result in any litigation or defense proceedings could put one or more of our patents at risk of being invalidated or interpreted narrowly and could put our patent applications at risk of not issuing. The initiation of a claim against a third-party may also cause the third-party to bring counter claims against us such as claims asserting that our patents are invalid or unenforceable. In patent litigation in the U.S., defendant counterclaims alleging invalidity or unenforceability are commonplace. Grounds for a validity challenge could be an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness, non-enablement or lack of statutory subject matter. Grounds for an unenforceability assertion could be an allegation that someone connected with prosecution of the patent withheld relevant material information from the USPTO, or made a materially misleading statement, during prosecution. Third parties may also raise similar validity claims before the USPTO in post-grant proceedings such as inter partes review, or post-grant review, or oppositions or similar proceedings outside the U.S., in parallel with litigation or even outside the context of litigation. The outcome following legal assertions of invalidity and unenforceability is unpredictable. We cannot be certain that there is no invalidating prior art, of which we and the patent examiner were unaware during prosecution. For the patents and patent applications that we have licensed, we may have limited or no right to participate in the defense of any licensed patents against challenge by a third-party. If a defendant were to prevail on a legal assertion of invalidity or unenforceability, we would lose at least part, and perhaps all, of any future patent protection on our current or future product candidates. Such a loss of patent protection could harm our business.

We may not be able to prevent, alone or with our licensors, misappropriation of our intellectual property rights, particularly in countries where the laws may not protect those rights as fully as in the U.S. Our business could be harmed if in litigation the prevailing party does not offer us a license on commercially reasonable terms. Any litigation or other proceedings to enforce our intellectual property rights may fail, and even if successful, may result in substantial costs and distract our management and other employees.

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			Incorporated by Reference
Exhibit Number		Description	Schedule/ Form	File Number	Exhibit		File Date
	10.15#	Vaxart, Inc. Amended and Restated 2007 Equity Incentive Plan, Stock Option Agreement, form of Notice of Stock Option Grant, form of Additional Terms and Conditions to Option and Stock Option Exercise Agreement	S-4/A	333-222009		10.24	December 29, 2017
	10.16#	Offer Letter, dated May 25, 2011, and Amendment to Offer Letter and Option Grant Agreement, dated October 1, 2011, by and between Vaxart, Inc. and Wouter W. Latour, M.D.	S-4/A	333-222009		10.25	December 29, 2017
	10.17	Industrial Lease dated October 28, 2013, by and between Vaxart, Inc. and Oyster Point LLC	S-4/A	333-222009		10.26	December 29, 2017
	10.18	Lease Agreement dated April 17, 2015, by and between Vaxart, Inc. and CRP Edgewater, LLC	S-4/A	333-222009		10.27	December 29, 2017
	10.19	Loan and Security Agreement dated December 22, 2016, by and between Vaxart, Inc. and Oxford Finance LLC	S-4/A	333-222009		10.28	December 29, 2017
	10.20	Second Amendment to the Loan Agreement, dated February 13, 2018, between Vaxart, Inc. and Oxford Finance LLC	8-K	001-35285		10.1	February 20, 2018
	10.21#	Severance Benefit Plan and Form of Severance Benefit Plan Participation Notice	8-K	001-35285		10.1	June 6, 2018
	10.22	Settlement Agreement by and among Vaxart, Inc., Digirad Corporation, East Hill Management Company, LLC, and Aviragen Therapeutics, Inc.	8-K	001-35285		10.1	February 9, 2018
	10.23	Form of Sales Agreement dated December 19, 2018 by and between Vaxart, Inc. and B. Riley FBR, Inc.	S-3	333-228910		1.2	December 20, 2018
	10.24	Amended and Restated Warrant issued to Oxford Finance LLC, dated February 13, 2018	8-K	001-35285		10.2	February 20, 2018

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation. There could also be public announcements of the results of hearings, motions or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, it could have an adverse effect on the price of our common stock.

~~II-5~~If a third party claims we are infringing on its intellectual property rights, we could incur significant expenses or be prevented from further developing or commercializing our product candidates, which could materially harm our business.

Our success will largely depend on our ability to operate without infringing the patents and other proprietary intellectual property rights of third parties. This is generally referred to as having the “freedom to operate.” However, our research, development and commercialization activities may be subject to claims that we infringe or otherwise violate patents or other intellectual property rights owned or controlled by third parties. Numerous U.S. and foreign issued patents and pending patent applications, which are owned by third parties, exist in the fields in which we are pursuing development candidates. As the biotechnology and pharmaceutical industries expand and more patents are issued, the risk increases that our current or future product candidates may be subject to claims of infringement of the patent rights of third parties. The biotechnology and pharmaceutical industries are characterized by extensive litigation regarding patents and other intellectual property rights. The defense and prosecution of intellectual property claims, interference proceedings and related legal and administrative proceedings, both in the U.S. and internationally, involve complex legal and factual questions. As a result, such proceedings are lengthy, costly and time-consuming, and their outcome is highly uncertain. We may become involved in protracted and expensive litigation in order to determine the enforceability, scope and validity of the proprietary rights of others, or to determine whether we have the freedom to operate with respect to the intellectual property rights of others.

Patent applications in the U.S. are, in most cases, maintained in secrecy until approximately 18 months after the patent application is filed. The publication of discoveries in scientific or patent literature frequently occurs substantially later than the date on which the underlying discoveries were made. Therefore, patent applications relating to product candidates similar to ours may have already been filed by others without our knowledge. In the event that a third party has also filed a patent application covering our product candidate or other claims, we may have to participate in an adversarial proceeding, known as an interference proceeding, in the USPTO, or similar proceedings in other countries, to determine the priority of invention. In the event an infringement claim is brought against us, we may be required to pay substantial legal fees and other expenses to defend such a claim and, should we be unsuccessful in defending the claim, we may be prevented from pursuing the development and commercialization of a product candidate and may be subject to injunctions and/or damage awards.

In the future, the USPTO or a foreign patent office may grant patent rights to our product candidates or other claims to third parties. Subject to the issuance of these future patents, the claims of which will be unknown until issued, we may need to obtain a license or sublicense to these rights in order to have the appropriate freedom to further develop or commercialize them. Any required licenses may not be available to us on acceptable terms, if at all. If we need to obtain such licenses or sublicenses, but are unable to do so, we could encounter delays in the development of our product candidates, or be prevented from developing, manufacturing and commercializing our product candidates at all. If it is determined that we have infringed an issued patent and do not have the freedom to operate, we could be subject to injunctions, and/or compelled to pay significant damages, including punitive damages. In cases where we have in-licensed intellectual property, our failure to comply with the terms and conditions of such agreements could harm our business.

It is becoming common for third parties to challenge patent claims on any successfully developed product candidate or approved drug. If we or our licensees or collaborators become involved in any patent litigation, interference or other legal proceedings, we could incur substantial expense, and the efforts and attention of our technical and management personnel could be significantly diverted. A negative outcome of such litigation or proceedings may expose us to the loss of our proprietary position or to significant liabilities or require us to seek licenses that may not be available from third parties on commercially acceptable terms, if at all. We may be restricted or prevented from developing, manufacturing and selling our product candidates in the event of an adverse determination in a judicial or administrative proceeding, or if we fail to obtain necessary licenses.

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			Incorporated by Reference
Exhibit Number		Description	Schedule/ Form	File Number	Exhibit		File Date
	10.25	Form of Securities Purchase Agreement dated as of March 19, 2019, by and among Vaxart, Inc. and the Purchasers named therein	8-K	001-35285		10.1	March 20, 2019
	10.26	Form of Placement Agent Warrant	8-K	001-35285		10.3	March 20, 2019
	10.27#	2019 Equity Incentive Plan	8-K	001-35285		10.1	April 24, 2019
	10.28#	Form of Stock Option Grant Notice, Stock Option Agreement and Notice of Exercise under the 2019 Equity Incentive Plan	8-K	001-35285		10.2	April 24, 2019
	10.29#	Form of Restricted Stock Unit Grant Notice and Restricted Stock Unit Award Agreement and Notice of Exercise under the 2019 Equity Incentive Plan	8-K	001-35285		10.3	April 24, 2019
	10.30*+	Manufacturing Services Agreement dated July 17, 2019, by and between Vaxart, Inc. and Lonza Houston, Inc.
	16.1	Letter dated February 16, 2018 from Ernst & Young LLP to the Securities and Exchange Commission	8-K	001-35285		16.1	February 20, 2018
	21.1	List of Subsidiaries	10-K	001-35285		21.1	February 6, 2019
	23.1	Consent of KPMG LLP, Independent Registered Public Accounting Firm
	23.2*	Consent of Cooley LLP is contained in Exhibit 5.1 to this Registration Statement
	24.1	Power of Attorney (see the signature page to this registration statement on Form S-1)

Obtaining and maintaining our patent protection depends on compliance with various procedures, document submission, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements.

Periodic *To maintenance fees on any issued patent are due to be ~~filed~~paid to the USPTO and foreign patent agencies in several stages over the lifetime of the patent. The USPTO and various foreign governmental patent agencies require compliance with several procedures, documentary fee payments and other provisions during the patent application process. While an inadvertent lapse can in many cases be cured by ~~amendment #Management contract~~payment of a late fee or ~~compensation~~by ~~plan~~other means in accordance with the applicable rules, there are situations in which noncompliance can result in abandonment or ~~arrangement. +Portions~~ lapse of ~~this~~the ~~exhibit~~patent ~~(indicated~~or bypatent ~~asterisks)~~application, ~~have~~resulting ~~been~~in ~~omitted~~partial asor complete loss of patent rights in the ~~Registrant~~relevant ~~has~~jurisdiction. ~~determined~~Non-compliance events that ~~(i) the~~could ~~omitted~~result ~~information~~in isabandonment or lapse of a patent or patent application include, but are not ~~material~~limited to, failure to respond to official actions within prescribed time limits, non-payment of fees and ~~(ii) the~~ ~~omitted~~failure ~~information~~to ~~would~~properly ~~likely~~legalize ~~cause~~and ~~competitive~~submit ~~harm~~formal documents. If we and our licensors fail to maintain the ~~Registrant~~patents ifand ~~publicly~~patent ~~disclosed.~~ applications covering our product candidates, our competitive position would be adversely affected.

~~II-6~~Changes in U.S. patent law could diminish the value of patents in general, thereby impairing our ability to protect our product candidates.

The U.S. has recently enacted and implemented wide-ranging patent reform legislation. The United States Supreme Court has ruled on several patent cases in recent years, either narrowing the scope of patent protection available in certain circumstances or weakening the rights of patent owners in certain situations. In addition to increasing uncertainty with regard to our ability to obtain patents in the future, this combination of events has created uncertainty with respect to the value of patents, once obtained. Depending on actions by the U.S. Congress, the federal courts, and the USPTO, the laws and regulations governing patents could change in unpredictable ways that would weaken our ability to obtain new patents or to enforce patents that we have licensed or that we might obtain in the future.

We may not be able to protect our intellectual property rights throughout the world, which could impair our business.

Filing, prosecuting and defending patents covering our product candidates throughout the world would be prohibitively expensive. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own vaccines and, further, may export otherwise infringing vaccines to territories where we may obtain patent protection, but where patent enforcement is not as strong as that in the U.S. These vaccines may compete with our product candidates in jurisdictions where we do not have any issued or licensed patents and any future patent claims or other intellectual property rights may not be effective or sufficient to prevent them from so competing.

We may be subject to claims that our employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties or that our employees have wrongfully used or disclosed alleged trade secrets of their former employers.

Many of our employees, including our senior management, were previously employed at universities or other biotechnology or pharmaceutical companies. These employees typically executed proprietary rights, non-disclosure and non-competition agreements in connection with their previous employment. Although we try to ensure that our employees do not use the proprietary information or know-how of others in their work for us, we may be subject to claims that it or these employees have used or disclosed intellectual property, including trade secrets or other proprietary information, of any such employee’s former employer. We are not aware of any threatened or pending claims related to these matters, but in the future, litigation may be necessary to defend against such claims. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management.

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~~Financial statement~~Our ~~schedules~~reliance ~~have~~on ~~been~~third ~~omitted,~~parties asrequires ~~the~~us ~~information required~~ to beshare ~~set~~our ~~forth~~trade ~~therein~~secrets, iswhich ~~included~~increases in the ~~Consolidated~~possibility ~~Financial~~that ~~Statements~~a orcompetitor ~~Notes~~will ~~thereto~~discover ~~appearing~~them ~~in the~~or ~~prospectus~~that ~~made~~our ~~part~~trade ofsecrets ~~this~~will ~~registration~~be ~~statement~~misappropriated or disclosed.

We ~~ITEM~~seek 17to protect our proprietary technology in part by entering into confidentiality agreements with third parties and, if applicable, material transfer agreements, consulting agreements or other similar agreements with our advisors, employees, third-party contractors and consultants prior to beginning research or disclosing proprietary information. ~~UNDERTAKINGS~~ These agreements typically limit the rights of the third parties to use or disclose our confidential information, including our trade secrets. Despite the contractual provisions employed when working with third parties, the need to share trade secrets and other confidential information increases the risk that such trade secrets become known by our competitors, are inadvertently incorporated into the technology of others, or are disclosed or used in violation of these agreements. Given that our proprietary position is based, in part, on our know-how and trade secrets, a competitor’s discovery of our trade secrets or other unauthorized use or disclosure would impair our competitive position and may have an adverse effect on our business and results of operations.

~~Insofar~~In asaddition, ~~indemnification~~these ~~for~~agreements ~~liabilities~~typically ~~arising~~restrict ~~under~~ the ~~Securities~~ability ~~Act may be permitted to directors, officers and controlling persons~~ of ~~the~~ ~~Registrant~~our ~~pursuant to the foregoing provisions~~advisors, ~~or otherwise~~employees, ~~the~~third-party ~~Registrant~~contractors ~~has~~and ~~been~~consultants ~~advised~~to ~~that~~publish indata ~~the~~potentially ~~opinion~~relating ofto ~~the~~our ~~SEC~~trade ~~such~~secrets, ~~indemnification~~although isour ~~against~~agreements ~~public~~may ~~policy~~contain ascertain ~~expressed~~limited inpublication ~~the Securities Act and is, therefore, unenforceable~~rights. InDespite ~~the~~our ~~event~~efforts ~~that~~to aprotect ~~claim~~our ~~for~~trade ~~indemnification~~secrets, ~~against~~our ~~such~~competitors ~~liabilities~~may ~~(other~~discover ~~than~~our ~~the~~trade ~~payment by the Registrant of expenses incurred or paid by a director~~secrets, ~~officer~~either orthrough ~~controlling~~breach ~~person~~ of ~~the~~our ~~Registrant~~agreements inwith ~~the~~third ~~successful defense of any action~~parties, ~~suit~~independent ~~or proceeding) is asserted by such director~~development, ~~officer~~ or ~~controlling~~publication ~~person in connection with the securities being registered, the Registrant will, unless in the opinion~~ of ~~its~~information ~~counsel the matter has been settled~~ by ~~controlling~~any ~~precedent, submit to a court~~ of ~~appropriate~~our ~~jurisdiction~~third-party ~~the question~~collaborators. ~~whether~~A ~~such~~competitor’s ~~indemnification~~discovery byof itour istrade ~~against~~secrets ~~public~~would ~~policy~~impair asour ~~expressed~~competitive inposition ~~the Securities Act~~ and ~~will~~have bean ~~governed~~adverse byimpact ~~the~~on ~~final~~our ~~adjudication of such issue~~business.

~~The undersigned~~Patent ~~Registrant~~terms ~~hereby~~may ~~undertakes:~~be inadequate to protect our competitive position on our product candidates for an adequate amount of time.

~~(i) To include~~Patents ~~any~~have ~~prospectus~~a ~~required~~limited bylifespan. ~~Section 10(~~In the U.S., if all maintenance fees are timely paid, the natural expiration of a~~)(3)~~ patent is generally 20 years from its earliest U.S. non-provisional filing date. Various extensions may be available, but the life of a patent, and the ~~Securities~~protection ~~Act~~it affords, is limited. Even if patents covering our product candidates are obtained, once the patent life has expired for a product candidate, we may be open to competition from competitive vaccines and medications, including generic medications. Given the amount of ~~1933;~~time required for the development, testing and regulatory review of new product candidates, patents protecting such product candidates might expire before or shortly after such product candidates are commercialized. As a result, our owned and licensed patent portfolio may not provide us with sufficient rights to exclude others from commercializing product candidates similar or identical to ours.

~~(ii) To reflect~~Depending inupon the ~~prospectus~~timing, duration and conditions of any ~~facts~~FDA marketing approval of our product candidates, one or ~~events~~more ~~arising~~of ~~after~~our U.S. patents may be eligible for limited patent term extension under the ~~effective~~Drug ~~date~~Price Competition and Patent Term Restoration Act of 1984, referred to as the ~~registration~~Hatch-Waxman ~~statement~~Amendments, ~~(or~~and similar legislation in the ~~most~~European ~~recent~~Union. ~~post~~The Hatch-~~effective~~Waxman ~~amendment~~Amendments ~~thereof) which,~~permit ~~individually~~a orpatent interm ~~the~~extension ~~aggregate,~~of ~~represent~~up to five years for a ~~fundamental~~patent ~~change~~covering inan ~~the~~approved ~~information~~product ~~set~~as ~~forth~~compensation infor effective patent term lost during product development and the ~~registration~~FDA ~~statement~~regulatory review process. ~~Notwithstanding~~However, we may not receive an extension if we fail to exercise due diligence during the ~~foregoing~~testing phase or regulatory review process, ~~any~~fail ~~increase~~to orapply ~~decrease~~within inapplicable ~~volume~~deadlines, fail to apply prior to expiration of ~~securities~~ ~~offered~~relevant ~~(if~~patents ~~the~~or ~~total~~otherwise ~~dollar~~fail ~~value~~to satisfy applicable requirements. Moreover, the length of ~~securities~~the ~~offered~~extension ~~would~~could ~~not~~be ~~exceed~~less ~~that~~than ~~which~~we ~~was~~request. ~~registered)~~Only ~~and~~one ~~any~~patent ~~deviation~~per ~~from~~approved product can be extended, the ~~low~~extension orcannot ~~high~~extend ~~end~~the oftotal patent term beyond 14 years from approval and only those claims covering the ~~estimated~~approved ~~maximum~~drug, ~~offering~~a ~~range~~method for using it or a method for manufacturing it may be ~~reflected~~extended. inIf we are unable to obtain patent term extension or the ~~form~~term of ~~prospectus~~any ~~filed~~such ~~with~~extension is less than we request, the ~~Commission~~period ~~pursuant~~during which we can enforce our patent rights for the applicable product candidate will be shortened and our competitors may obtain approval to ~~Rule 424(b)~~market ifcompeting products sooner. As a result, inour ~~the~~revenue ~~aggregate~~from applicable products could be reduced. Further, ~~the~~if ~~changes~~this occurs, our competitors may take advantage of our investment in ~~volume~~development and ~~price~~trials ~~represent~~by noreferencing ~~more~~our ~~than~~clinical ~~20 percent~~and ~~change~~preclinical ~~in the~~data ~~maximum~~and ~~aggregate~~launch ~~offering~~their ~~price~~product ~~set~~earlier ~~forth~~than inmight otherwise be the ~~"Calculation~~case, ofand ~~Registration~~our ~~Fee"~~competitive ~~table~~position, inbusiness, ~~the~~financial ~~effective~~condition, ~~registration~~results ~~statement;~~of operations and prospects could be materially harmed.

~~(iii) To~~ ~~include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such~~ 53 ~~information in the registration statement;~~

II-7

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~~communications,~~ While the ~~undersigned~~appeal ~~Registrant~~of ~~will~~the beopposition proceeding of a ~~seller~~Vaxart European patent in the European Patent Office is completed, we must now obtain approval of the specification conformed to the ~~purchaser~~new claims and it is possible this will be ~~considered~~delayed toand ~~offer~~would ordelay ~~sell~~revalidation ~~such~~of ~~securities~~the patent in various European countries. If revalidation of the application was delayed, we may be delayed in asserting the patent to ~~such~~prevent ~~purchaser:~~others in Europe from copying some of our product candidates.

We recently concluded the appeal portion of an opposition proceeding of one of our European patents in the European Patent Office (i“EPO”) ~~Any preliminary~~. ~~prospectus~~European orPatent ~~prospectus~~No. 3307239, which had claims directed to vaccine compositions for norovirus and RSV, was opposed in the EPO. The opposition challenged the validity of European Patent No. 3307239 and the ~~undersigned~~EPO ~~Registrant~~maintained ~~relating~~the patent with the original independent claim and with cancelation of some subject matter from dependent claims. The opponent appealed this decision and the Board of Appeal upheld the claims to the ~~offering~~extent ~~required~~they were directed to benorovirus ~~filed~~vaccine ~~pursuant~~compositions, but removed claim subject matter as it related to ~~Rule 424~~RSV ~~(§230~~vaccine compositions.~~424~~ The specification was conformed to the new claims and the Opponents had until March 23, 2026 to object to any of the changes made. This might delay the ultimate reissue of the EP patent and its revalidation in various European states. It is feasible this ~~chapter);~~may delay Vaxart from asserting the patent in Europe until these formalities are resolved.

~~(ii) Any free~~We ~~writing~~may ~~prospectus~~be ~~relating~~subject to ~~the~~claims ~~offering~~challenging ~~prepared~~the byinventorship ~~or on behalf~~ of ~~the~~our ~~undersigned~~patents ~~Registrant~~and orother ~~used~~intellectual ~~or referred to by the undersigned Registrant;~~ property.

~~(iii) The portion~~We ofor ~~any~~our licensors may be subject to claims that former employees, collaborators or other ~~free~~third ~~writing~~parties ~~prospectus~~have ~~relating~~an interest in our patents, trade secrets, or other intellectual property as an inventor or co-inventor. For example, we or our licensors may have inventorship disputes arise from conflicting obligations of employees, consultants or others who are involved in developing our product candidates. Litigation may be necessary to ~~the~~defend ~~offering~~against ~~containing~~these ~~material~~and ~~information~~other ~~about~~claims ~~the~~challenging ~~undersigned~~inventorship ~~Registrant~~or our or ~~its~~our ~~securities~~licensors’ ~~provided by~~ownership of our patents, trade secrets or onother ~~behalf~~intellectual property. If we or our licensors fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, intellectual property that is important to our product candidates. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees. Any of the ~~undersigned~~foregoing ~~Registrant;~~could have a material adverse effect on our business, financial condition, results of operations and prospects.

~~(iv) Any other~~General ~~communication~~Risk ~~that is an offer in the offering made by the undersigned Registrant to the purchaser.~~ Factors

~~II-8~~Raising additional funds by issuing securities may cause dilution to existing stockholders, and raising funds through lending and licensing arrangements may restrict our operations or require us to relinquish proprietary rights.

We expect that significant additional capital will be needed in the future to continue our planned operations. Until such time, if ever, as we can generate substantial product revenues, we expect to finance our cash needs through a combination of equity offerings, royalties, debt financings, strategic alliances and license and development agreements in connection with any collaborations. We do not currently have any committed external source of funds. To the extent that we raise additional capital by issuing equity securities, our existing stockholders’ ownership may experience substantial dilution, and the terms of these securities may include liquidation or other preferences that adversely affect our common stockholders’ rights. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures, declaring dividends, creating liens, redeeming our stock or making investments.

Future sales of shares by existing stockholders could cause our stock price to decline.

If our existing stockholders sell, or indicate an intention to sell, substantial amounts of our common stock in the public market, the trading price of our common stock could decline. Sales of a substantial number of shares of our common stock in the public market, or the perception that the sales might occur, could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. We are unable to predict the effect that sales may have on the prevailing market price of our common stock.

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Changes in ~~SIGNATURES~~ tax laws and regulations or in our operations may impact our effective tax rate and may adversely affect our business, financial condition and operating results.

~~Pursuant~~Changes toin ~~the~~tax ~~requirements~~laws ofin ~~the~~any ~~Securities~~jurisdiction ~~Act~~in ofwhich ~~1933~~we operate, ~~the~~or ~~Registrant~~adverse ~~has~~outcomes ~~duly~~from ~~caused~~any ~~this~~tax ~~Registration~~audits ~~Statement~~that towe may be ~~signed~~subject onto ~~its behalf~~in byany ~~the~~such ~~undersigned~~jurisdictions, could result in ~~the~~an ~~City~~unfavorable ofchange ~~South~~in ~~San~~our ~~Francisco~~effective tax rate in the future, ~~State~~which ofcould ~~California~~adversely affect our business, onfinancial ~~September 11~~condition, ~~2019.~~and operating results.

~~VAXART,~~Anti-takeover ~~INC.~~provisions ~~By:~~under ~~/s/~~Delaware ~~WOUTER~~law W.could ~~LATOUR,~~make ~~M.D.~~an ~~Wouter~~acquisition W.more ~~Latour,~~difficult ~~M.D.~~and ~~President~~may ~~and~~prevent ~~Chief~~attempts ~~Executive~~by ~~Officer~~our stockholders to replace or remove our management.

Because ~~POWER~~we OFare ~~ATTORNEY~~ incorporated in Delaware, we are governed by the provisions of Section 203 of the DGCL, which prohibits stockholders owning in excess of 15% of the outstanding company voting stock from merging or combining with the company. Although we believe these provisions collectively provide for an opportunity to receive higher bids by requiring potential acquirers to negotiate with our board of directors, they would apply even if the offer was considered beneficial by some stockholders. In addition, these provisions may frustrate or prevent any attempts by our stockholders to replace or remove management by making it more difficult for stockholders to replace members of our board of directors, which is responsible for appointing the members of management.

~~KNOW~~Our ~~ALL~~business ~~PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes~~ and ~~appoints~~operations ~~Wouter~~would W.suffer ~~Latour, M.D. and Margaret A. Echerd, and each of them, as true and lawful attorneys-~~in~~-fact~~ and agents, with full powers of substitution and resubstitution, for them and in their name, place and stead, in any and all capacities, to sign any and all amendments (including pre-effective and post-effective amendments) to this registration statement, and to sign any registration statement for the ~~same~~event ~~offering covered by this registration statement that is to be effective upon filing pursuant to Rule 462 under the Securities Act~~ of ~~1933,~~system asfailures amended, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, and generally to do all such things in their names and behalf in their capacities as officers and directors to enable Vaxart, Inc. to comply with the provisions of the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or ~~she~~cybersecurity might or could do in person, ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or his or her substitutes or substitute, may lawfully do or cause to be done by virtue hereofbreaches.

~~Pursuant~~ Our business and operations, including our CROs, as well as the operations and systems of entities whose services are necessary to our operations, rely greatly on information technology systems and are vulnerable to damage in the ~~requirements~~event of failure, natural disasters, security breaches and attacks, interruptions or other cybersecurity incidents. These events may compromise the ~~Securities~~stability, ~~Act~~integrity, or confidentiality of ~~1933~~these systems, ~~this~~and ~~Registration~~the ~~Statement~~accuracy ~~has~~and ~~been~~integrity ~~signed~~of ~~below~~information bystored or processed through these systems, and may significantly interrupt our ability to run the ~~following~~business ~~persons~~successfully. Ransomware attacks, which are becoming increasingly common across all industry sectors and have focused in part on businesses operating in health care markets, can disrupt and even halt ongoing business operations completely. Increasing global tensions, including the ~~capacities~~ongoing military conflict between Russia and onUkraine, among others, are likely to increase the ~~dates~~frequency ~~indicated.~~of cybersecurity incidents.

Signatures	Title	Date
/s/ WOUTER W. LATOUR, M.D. Wouter W. Latour, M.D.	President, Chief Executive Officer and Director (Principal Executive Officer and Principal Financial Officer)	September 11, 2019
/s/ MARGARET A. ECHERD Margaret A. Echerd	Vice President, Corporate Controller (Principal Accounting Officer)	September 11, 2019
/s/ RICHARD J. MARKHAM Richard J. Markham	Chairman of the Board	September 11, 2019

Our systems, including onsite datacenters and cloud services, continue to increase in size and complexity, making them potentially vulnerable to breakdowns and other disruptions. Disruptions include issues with routine maintenance, upgrades, and patching. These systems continue to become more critical and integrated within our business, especially as we continue to work remotely, and our dependence on them will continue to increase. We rely on the high-availability and redundancies built into our cloud services, but these systems are managed and maintained by the providers and are out of our direct control. Any potential problems and interruptions associated with the implementation, support, security, availability, or maintenance of new or existing systems could disrupt or reduce the efficiency of our operations and materially impact the delivery of development programs.

IICybersecurity incidents, including phishing and spear phishing attacks, distributed denial of service attacks, man-9in-the-middle attacks, as well as ransomware and other malware insertions, are becoming more sophisticated and frequent. If these attempts to misappropriate or compromise confidential or proprietary information or infiltrate or sabotage enterprise IT systems were successful, they could result in a loss of or damage to data or applications and even the interruption of basic business operations and financial loss, as well as the risk of legal and regulatory liability. As a result, further development of our product candidates could be substantially delayed. A data breach could risk the exposure of mission critical data or other intellectual property, or expose PII (Personally Identifiable Information) and PHI (Protected Health Information) of company employees or people participating in clinical trials. A successful phishing attempt could lead to further hacking attempts, unauthorized email access or messaging, or other vertical/horizontal cyberattacks. Any of these events could cause substantial reputational injury impacting our business.

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Signatures	Title	Date
/s/ MICHAEL J. FINNEY, PH.D. Michael J. Finney, Ph.D.	Director	September 11, 2019
/s/ ANNE M. VANLENT Anne M. VanLent	Director	September 11, 2019
/s/ GEOFFREY F. COX, PH.D. Geoffrey F. Cox, Ph.D.	Director	September 11, 2019
/s/ JOHN P. RICHARD John P. Richard	Director	September 11, 2019

Our business could be adversely affected by economic downturns, changes in inflation and interest rates, changes in trade policy, natural disasters, political crises, geopolitical events, such as the ongoing military conflict between Russia and Ukraine and the war involving Israel, or other macroeconomic conditions, which may in the future negatively impact our business and financial performance.

~~II-10~~The global economy, including credit and financial markets, has experienced extreme volatility and disruptions, including, among other things, severely diminished liquidity and credit availability, declines in consumer confidence, declines in economic growth, supply chain shortages, changes in inflation and interest rates, and uncertainty about economic stability. For example, during 2022 and 2023, the Federal Reserve raised interest rates multiple times in response to concerns about inflation. Higher interest rates, coupled with reduced government spending and volatility in financial markets may increase economic uncertainty and affect consumer spending. Trade policies and geopolitical disputes and conflicts can result in tariffs, sanctions and other measures that restrict international trade, and may adversely affect our costs of doing business, particularly if these measures occur in regions where our suppliers source components or raw materials. Similarly, the ongoing military conflict between Russia and Ukraine and the war involving Israel have created volatility in the global capital markets and are expected to have further global economic consequences, including disruptions of the global supply chain and energy markets.

Additionally, trade policies and geopolitical disputes and other international conflicts can result in tariffs, sanctions, and other measures that restrict international trade, and can materially adversely affect our business, particularly if these measures occur in regions where drug products are manufactured or raw materials are sourced. With the new presidential administration in the U.S. in 2025, additional and higher tariffs and sanctions may be imposed on goods imported from other countries which could increase the cost of goods needed to commercialize our products and continue development of our product candidates. Further, such actions by the U.S. could result in retaliatory action by those countries which could impact our ability to profitably commercialize our products in those jurisdictions in the future. As a result, our business, operations and financial condition could be materially harmed.

Any such volatility and disruptions may adversely affect our business or the third parties on whom we rely. If the equity and credit markets deteriorate, including as a result of political unrest or war, it may make any necessary debt or equity financing more difficult to obtain in a timely manner or on favorable terms, more costly or more dilutive. Increased inflation rates can adversely affect us by increasing our costs, including labor and employee benefit costs.

Artificial intelligence (“AI”) presents risks and challenges that can impact our business including by posing security risks to our confidential information, proprietary information and personal data.

We incorporate AI solutions into our platform, and these applications may become important in our operations over time. AI presents risks such as inaccuracy, bias, toxicity, intellectual property infringement or misappropriation, data privacy and cybersecurity and data provenance. In addition, AI utilizes machine learning and predictive analytics, which may present flawed, biased, and inaccurate results, and may have errors or inadequacies that are not easily detectable and may also be subject to data herding and interconnectedness (i.e., multiple market participants utilizing the same data), in each case adversely impacting our business. These issues, combined with an uncertain regulatory environment, may further result in reputational harm, liability, or other adverse consequences to our business operations. Our vendors may incorporate generative AI tools into their offerings without disclosing this use to us, and the providers of these generative AI tools may not meet existing or rapidly evolving regulatory or industry standards with respect to privacy and data protection and may inhibit our or our vendors’ ability to maintain an adequate level of service and experience. If our vendors, or our third-party partners experience an actual or perceived breach or privacy or security incident because of the use of generative AI, we may lose valuable intellectual property and confidential information and our reputation and the public perception of the effectiveness of our security measures could be harmed. Further, bad actors around the world use increasingly sophisticated methods, including the use of AI, to engage in illegal activities involving the theft and misuse of personal information, confidential information, and intellectual property. Any of these outcomes could damage our reputation, result in the loss of valuable property and information, and adversely impact our business.

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If we fail to maintain an effective system of internal controls, we may not be able to accurately report our financial results or detect fraud. Consequently, investors could lose confidence in our financial reporting and this may negatively impact the trading price of our common stock.

We are required, pursuant to Section 404 of the Sarbanes-Oxley Act, to furnish a quarterly report by management on, among other things, the effectiveness of our internal control over financial reporting. This assessment needs to include disclosure of any material weaknesses identified by our management in our internal control over financial reporting. We are required to disclose changes made in our internal control over financial reporting on a quarterly basis. We must also provide an auditor’s attestation report on management’s assessment of the effectiveness of our system of internal control over financial reporting pursuant to Section 404(b) of the Sarbanes-Oxley Act.

We must maintain effective disclosure and internal controls to provide reliable financial reports. We have been assessing our controls to identify areas that need improvement. Based on our evaluation as of December 31, 2025, we concluded that our internal controls and procedures were effective as of December 31, 2025, however we have identified material weaknesses in the past and may do so again in the future. A “material weakness” is a deficiency, or a combination of deficiencies, in internal control over financial reporting such that there is a reasonable possibility that a material misstatement of our annual or interim consolidated financial statements will not be prevented or detected on a timely basis. Failure to maintain the improvements in our controls as necessary to maintain an effective system of such controls could harm our ability to accurately report our operating results and cause investors to lose confidence in our reported financial information. Any such loss of confidence would have a negative effect on the trading price of our common stock.

Most of our facilities are located near known earthquake fault zones. The occurrence of an earthquake, fire or any other catastrophic event could disrupt our operations or the operations of third parties who provide vital support functions to us, which could have a material adverse effect on our business and financial condition.

We are vulnerable to damage from catastrophic events, such as power loss, natural disasters, terrorism and similar unforeseen events beyond our control. The majority of our operations are located in the San Francisco Bay Area, which in the past has experienced severe earthquakes and fires.

We do not have a disaster recovery and business continuity plan in place. Earthquakes, fires, floods, hurricanes or other natural disasters could severely disrupt our operations and have a material adverse effect on our business, results of operations, financial condition and prospects.

If a natural disaster, power outage or other event occurred that prevented us from using all or a significant portion of our headquarters, damaged critical infrastructure, such as our financial systems or manufacturing facility, or that otherwise disrupted our operations, it may be difficult or, in certain cases, impossible for us to continue business operations for a substantial period of time.

Natural disasters, including those resulting from significant climate change, could adversely affect our business and our third-party partners’ businesses.

Natural disasters, such as hurricanes, tornadoes, floods, wildfire, and drought may impact our operations or our partners’ businesses. Climate change is increasing the frequency, intensity, and duration of these weather events. These natural disasters, including those resulting from significant climate change, could destroy or damage facilities or other properties, disrupt business, increase the probability of power or other outages, or otherwise cause significant economic dislocation in the affected regions. Any of these situations may adversely affect our financial condition and results of operations.

Our business and operations are subject to risks related to climate change.

The long-term effects of global climate change could present both physical risks and transition risks (such as regulatory or technology changes), which are expected to be widespread and unpredictable. Transitional risks include, for example, a disorderly global transition away from fossil fuels that may result in increased energy prices; customer preference for low or no-carbon products; stakeholder pressure to decarbonize assets; or new legal or regulatory requirements that result in new or expanded carbon pricing, taxes, restrictions on greenhouse gas emissions, and increased greenhouse gas disclosure and transparency. These risks could increase operating costs, including the cost of our electricity and energy use, or other compliance costs. Physical risks to our operations include water stress and drought; flooding and storm surge; wildfires; extreme temperatures and storms, which could impact trials, increase costs, or disrupt supply chains. Our supply chain is likely subject to these same transitional and physical risks and would likely pass along any increased costs to us. We do not anticipate that these risks will have a material financial impact to the Company in the near term.

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Increased scrutiny of our environmental, social or governance responsibilities has and will likely continue to result in additional costs and risks and may adversely impact our reputation, employee retention and willingness of customers and suppliers to do business with us.

There is an increasing focus from certain customers, consumers, employees and other stakeholders concerning environmental, social and governance (“ESG”) matters, including corporate citizenship and sustainability. Additionally, public interest and legislative pressure related to public companies’ ESG practices continues to grow. If our ESG practices fail to meet regulatory requirements or stakeholders’ evolving expectations and standards for responsible corporate citizenship in areas including environmental stewardship, support for local communities, Board of Director and employee inclusion, human capital management, employee health and safety practices, corporate governance and transparency and employing ESG strategies in our operations, our brand, reputation and employee retention may be negatively impacted, and customers and suppliers may be unwilling to do business with us.

The trend of increased environmental regulation is not linear and can fluctuate depending on the administration and jurisdiction, even within the same county. For example, on January 20, 2025, President Trump issued Executive Orders seeking to rescind prior Executive Orders and agency actions enacted by the Biden Administration. These include revoking Biden-era Executive Orders withdrawing certain offshore waters within the Outer Continental Shelf available for oil and gas exploration and imposing a temporary prohibition of offshore wind leasing in the Outer Continental Shelf. We cannot foresee the potential impact and unintended consequences that future Executive Orders or the changes in enforcement of existing laws, rules, and orders may have on our business. Additionally, although the Trump Administration initially withdrew the U.S. from the Paris Agreement in November 2020, the U.S. reentered the Paris Agreement in February 2021 under the Biden Administration, but the Trump Administration again withdrew from the Paris Agreement on January 20, 2025. Though we are closely following developments in this area and changes in the regulatory landscape in the United States and other jurisdictions, we cannot predict with precision or quantify how or when challenges may arise and ultimately impact our business.

Additionally, in January 2025, President Trump signed a number of Executive Orders focused on diversity, equity, and inclusion (“DEI”), which indicate continued scrutiny of DEI initiatives and potential related investigations of certain private entities with respect to DEI initiatives, including publicly traded companies. If we do not successfully manage expectations across varied stakeholder interests, it could erode stakeholder trust, impact our reputation and constrain our investment opportunities. Such scrutiny of both ESG and DEI related practices could expose us to the risk of litigation, investigations, or challenges by federal or state authorities or result in reputational harm.

Nevertheless, as we work to align our ESG practices with industry standards, we have expanded and, in the future, will likely continue to expand our disclosures in these areas. From time-to-time, we communicate certain initiatives, including goals, regarding environmental matters, responsible sourcing and social investments. We also expect to incur additional costs and require additional resources to monitor, report and comply with our various ESG practices. The standards for tracking and reporting on ESG matters are relatively new, have not been harmonized and continue to evolve. The disclosure frameworks we choose to align with, if any, may change from time to time and may result in a lack of consistent or meaningful comparative data from period to period. Ensuring there are systems and processes in place to comply with various ESG tracking and reporting obligations will require management time and expense. In addition, our processes and controls may not always comply with evolving standards for identifying, measuring and reporting ESG metrics, our interpretation of reporting standards may differ from those of others and such standards may change over time, any of which could result in significant revisions to our goals or reported progress in achieving such goals.

If we fail to adopt ESG standards or practices as quickly as stakeholders desire, fail, or be perceived to fail, in our achievement of such initiatives or goals, or fail in fully and accurately reporting our progress on such initiatives and goals, our reputation, business, financial performance and growth may be adversely impacted. In addition, we could be criticized for the scope of such initiatives or goals or perceived as not acting responsibly in connection with these matters. Our business could be negatively impacted by such matters. Any such matters, or related corporate citizenship and sustainability matters, could have a material adverse effect on our business.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Exchange Act. These statements relate to future events or to our future operating or financial performance and involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. Forward-looking statements may include, but are not limited to, statements relating to:

	●	our ability to develop and commercialize our product candidates and clinical results and trial data;

	●	our ability to negotiate and receive royalty payments on the sales of our product candidates including Inavir;

	●	our ability to obtain the various synergies envisioned in the Exclusive License and Collaboration Agreement with Dynavax Technologies Corporation;

	●	estimates of selected financial results for future time periods;

	●	our ability to obtain, maintain, and enforce necessary patent and other intellectual property protection;

	●	potential partnership opportunities;

	●	expectations regarding the future contributions of our management team;

	●	the ability of our management team to build out the Company and drive sustainable growth and value creation;

	●	our ability to manufacture vaccine tablets;

	●	expectations regarding clinical results and trial data;

	●	expectations regarding the effectiveness, safety, or convenience of our norovirus vaccine candidate;

	●	expectations regarding the effectiveness, safety, or convenience of any other vaccine candidate;

	●	the anticipated use of proceeds from this offering; and

	●	our expectations with respect to the important advantages we believe our oral vaccine platform can offer over injectable alternatives.

In some cases, you can identify forward-looking statements by terms such as “aims,” “anticipates,” “assumes,” “believes,” “continue,” “could,” “expects,” “estimates,” “intends,” “may,” “plans,” “potential,” “will,” “would,” or the negative of these terms or other similar expressions. These statements reflect our current views with respect to future events and are based on estimates and assumptions and are subject to risks and uncertainties. Given these uncertainties, you should not place undue reliance on these forward-looking statements. We discuss in greater detail many of these risks in the section titled “Risk Factors”, in any prospectus supplement and free writing prospectuses we may authorize for use in connection with this offering, and in our most recent Annual Report on Form 10-K and Quarterly Reports on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC. Also, these forward-looking statements represent our estimates and assumptions only as of the date of the document containing the applicable statement. Unless required by law, we undertake no obligation to update or revise any forward-looking statements to reflect new information or future events or developments.

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In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this prospectus, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

You should read this prospectus and any free writing prospectus that we may authorize for use in connection with this offering, completely and with the understanding that our actual future results, levels of activity, performance and achievements may be materially different from what we expect. We qualify all of the forward-looking statements in this prospectus and any documents incorporated by reference herein by these cautionary statements. These cautionary statements qualify all forward-looking statements attributable to us or persons acting on our behalf.

OUR AGREEMENTS WITH LINCOLN PARK

Overview

This prospectus covers the resale by the selling stockholder of up to 32,914,599 shares of our common stock, comprised of: (i) up to 32,467,532 shares of our common stock that we may sell to Lincoln Park under the Purchase Agreement from time to time after the date of this prospectus and (ii) 447,067 Commitment Shares that we have already issued to Lincoln Park as a fee for making its irrevocable commitment to purchase our common stock under the Purchase Agreement.

General

On April 16, 2026, we entered into the Purchase Agreement with Lincoln Park, pursuant to which Lincoln Park has agreed to purchase from us up to an aggregate of $25 million of our common stock (subject to certain limitations) from time to time over the term of the Purchase Agreement. Pursuant to the Purchase Agreement we issued to Lincoln Park, as consideration for its irrevocable commitment, 447,067 Commitment Shares (for which Commitment Shares we have not and will not receive any cash consideration).

On April 16, 2026, we entered into a Registration Rights Agreement (the “Registration Rights Agreement”), pursuant to which we filed with the SEC the registration statement that includes this prospectus to register for resale under the Securities Act the shares of our common stock that have been or may be issued to Lincoln Park under the Purchase Agreement, for which we have not and will not receive any cash consideration.

We do not have the right to commence any sales of our common stock to Lincoln Park under the Purchase Agreement until all of the conditions set forth in the Purchase Agreement have been satisfied, including that the SEC has declared effective the registration statement that includes this prospectus and the final form of this prospectus has been filed with the SEC, which we refer to in this prospectus as the “Commencement,” and the date on which the Commencement occurs we refer to as the “Commencement Date.” From and after the Commencement, we may, from time to time and at our sole discretion for a period of 24-months, on any business day on which the closing sale price of our common stock is greater than $0.10, direct Lincoln Park to purchase up to 150,000 shares of our common stock, which maximum share limitation may be increased to up to 175,000 shares if the closing sale price is not below $0.50, up to 225,000 shares if the closing sale price is not below $0.75, and up to 275,000 shares if the closing sale price is not below $1.00, in each case subject to a maximum commitment of $500,000 per purchase, which we refer to in this prospectus as “Regular Purchases.” The foregoing share amounts and per share prices will be adjusted for any reorganization, recapitalization, non-cash dividend, stock split, reverse stock split or other similar transaction occurring after the date of the Purchase Agreement. In addition to Regular Purchases, if we direct Lincoln Park to purchase the maximum number of shares of our common stock that we may sell in a Regular Purchase on the applicable business day we initiate such Regular Purchase, then, in addition to such Regular Purchase, we may also direct Lincoln Park to purchase certain additional amounts of our common stock as “Accelerated Purchases” and as “Additional Accelerated Purchases.”

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We will control the timing and amount of any sales of our common stock to Lincoln Park. The purchase price of the shares of our common stock that may be sold to Lincoln Park in Regular Purchases, Accelerated Purchases, and Additional Accelerated Purchases under the Purchase Agreement will be based on the market price of our common stock at or prior to the time of sale as computed under the Purchase Agreement. The purchase price per share will be equitably adjusted as provided in the Purchase Agreement for any reorganization, recapitalization, non-cash dividend, stock split, or other similar transaction as set forth in the Purchase Agreement. We may at any time in our sole discretion terminate the Purchase Agreement without fee, penalty or cost upon one business day notice. Actual sales of shares of our common stock to Lincoln Park under the Purchase Agreement will depend on a variety of factors to be determined by us from time to time, including, among others, market conditions, the trading price of our common stock and determinations by us as to the appropriate sources of funding for our operations.

As of May 1, 2026, there were 241,973,011 shares of our common stock outstanding, which include the Commitment Shares. Although the Purchase Agreement provides that we may sell up to an aggregate of $25 million of our common stock to Lincoln Park, 32,914,599 shares of our common stock are being registered under the Securities Act for resale by Lincoln Park under the registration statement that includes this prospectus, which represents the 447,067 Commitment Shares that we issued to Lincoln Park on April 16, 2026 as a fee for making its irrevocable commitment to purchase our common stock at our direction under the Purchase Agreement and an additional 32,467,532 shares of our common stock that we may issue and sell to Lincoln Park as Purchase Shares from and after the Commencement under the Purchase Agreement, if and when we elect to sell shares of our common stock to Lincoln Park under the Purchase Agreement. Depending on the market prices of our common stock at the time we elect to issue and sell shares of our common stock to Lincoln Park under the Purchase Agreement, we may need to register under the Securities Act for resale by Lincoln Park additional shares of our common stock in order to receive aggregate gross proceeds equal to the $25 million total commitment available to us under the Purchase Agreement. If, in addition to the 447,067 Commitment Shares that we have issued or will issue to Lincoln Park, all of the 32,467,532 shares of our common stock that we may elect to issue and sell to Lincoln Park in the future as Purchase Shares that are being registered under the Securities Act for resale by Lincoln Park in the registration statement that includes this prospectus were issued and outstanding (without taking into account the Beneficial Ownership Cap limitations described below), such shares of our common stock, together with the 447,067 Commitment Shares would represent approximately 11.99% of the total number of shares of our common stock outstanding as of May 1, 2026 including all of the shares potentially issued to Lincoln Park under this Purchase Agreement. If we elect to issue and sell to Lincoln Park under the Purchase Agreement more than the 32,467,532 shares of our common stock that we may elect to issue and sell to Lincoln Park in the future as Purchase Shares that are being registered under the Securities Act for resale by Lincoln Park in the registration statement that includes this prospectus, which we have the right, but not the obligation, to do, we must first register under the Securities Act for resale by Lincoln Park any such additional shares of our common stock, which could cause additional substantial dilution to our stockholders. The number of shares of our common stock ultimately offered for resale by Lincoln Park is dependent upon the number of shares of our common stock we ultimately decide to sell to Lincoln Park under the Purchase Agreement.

The Purchase Agreement also prohibits us from directing Lincoln Park to purchase any shares of our common stock if those shares of our common stock, when aggregated with all other shares of our common stock then beneficially owned by Lincoln Park and its affiliates, would result in Lincoln Park having beneficial ownership, at any single point in time, of more than 4.99% of the then total outstanding shares of our common stock, as calculated pursuant to Section 13(d) of the Exchange Act and Rule 13d-3 thereunder, which limitation we refer to as the Beneficial Ownership Cap.

Issuances of our common stock to Lincoln Park under the Purchase Agreement will not affect the rights or privileges of our existing stockholders, except that the economic and voting interests of each of our existing stockholders will be diluted as a result of any such issuance. Although the number of shares of our common stock that our existing stockholders own will not decrease, the shares of our common stock owned by our existing stockholders will represent a smaller percentage of our total outstanding shares of our common stock after any such issuance of shares of our common stock to Lincoln Park under the Purchase Agreement. There are substantial risks to our stockholders as a result of the sale and issuance of common stock to Lincoln Park under the Purchase Agreement. See “Risk Factors.”

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Purchase of Shares of our Common Stock Under the Purchase Agreement

Regular Purchases

From and after the Commencement Date, provided the last closing sale price of our common stock on the applicable “regular purchase date” (as defined in the Purchase Agreement) is greater than $0.10 (and provided all shares of common stock subject to all prior Regular Purchases have been properly delivered to Lincoln Park in accordance with the Purchase Agreement), we may, by written notice delivered by us to Lincoln Park within the time periods on such Regular Purchase Date, direct Lincoln Park to purchase up to 150,000 shares of our common stock in a Regular Purchase; provided that this amount shall be increased to (i) up to 175,000 shares of our common stock, if the closing sale price of our common stock on the applicable Regular Purchase Date is not below $0.50, (ii) up to 225,000 shares of our common stock, if the closing sale price of our common stock on the applicable Regular Purchase Date is not below $0.75, and (iii) up to 275,000 shares of our common stock, if the closing sale price of our common stock on the applicable Regular Purchase Date is not below $1.00 (all of which share and dollar amounts shall be appropriately proportionately adjusted for any reorganization, recapitalization, non-cash dividend, stock split or other similar transaction) (such share amount limitation, the “Regular Purchase Share Limit”). In no event will Lincoln Park’s committed obligation under any single Regular Purchase exceed $500,000.

The purchase price per share for each Regular Purchase will be 97.0% of the lower of:

●

the lowest sale price for our common stock on the applicable Regular Purchase Date for such shares of our common stock; and

●

the average of the three lowest closing sale prices of our common stock during the 10-business day period immediately preceding the applicable Regular Purchase Date for such shares of our common stock.

Accelerated Purchases

In addition to Regular Purchases described above, we may also direct Lincoln Park, on any Regular Purchase Date on which we have properly submitted a Regular Purchase notice directing Lincoln Park to purchase the maximum number of shares of our common stock that we are then permitted to include in a single Regular Purchase notice (and provided all shares of common stock subject to all prior Regular Purchases, Accelerated Purchases and Additional Accelerated Purchases effected prior to such Regular Purchase Date have been properly delivered to Lincoln Park in accordance with the Purchase Agreement), to purchase an additional amount of our common stock, which we refer to as an “Accelerated Purchase”, on the business day immediately following the applicable Regular Purchase Date for such corresponding Regular Purchase, which we refer to as the “Accelerated Purchase Date,” not to exceed the lesser of:

• 30% of the aggregate number of shares of our common stock traded during all or, if certain trading volume or market price thresholds specified in the Purchase Agreement are crossed on the applicable Accelerated Purchase Date, the portion of the normal trading hours on the applicable Accelerated Purchase Date prior to such time that any one of such thresholds is crossed, which period of time on the applicable Accelerated Purchase Date we refer to herein as the “Accelerated Purchase Period”; and

• 300% of the number of purchase shares purchased pursuant to the corresponding Regular Purchase.

The purchase price per share for the shares subject to an Accelerated Purchase will be equal to 97% of the lower of:

• the volume weighted average price of our common stock during the Accelerated Purchase Period on the applicable Accelerated Purchase Date; and

• the closing sale price of our common stock on the applicable Accelerated Purchase Date.

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Additional Accelerated Purchases

We may also direct Lincoln Park, by written notice delivered to Lincoln Park, not later than 1:00 p.m., eastern time, on the same Accelerated Purchase Date on which an Accelerated Purchase Period for an Accelerated Purchase has ended prior to such time (and provided all shares of common stock subject to all prior Regular Purchases, Accelerated Purchases and Additional Accelerated Purchases, including those prior Accelerated Purchases and Additional Accelerated Purchases effected on the same Accelerated Purchase Date as the applicable Additional Accelerated Purchase have been properly delivered to Lincoln Park in accordance with the Purchase Agreement prior to such time), to purchase an additional amount of our common stock on such same Accelerated Purchase Date, which we refer to as an Additional Accelerated Purchase, of up to the lesser of:

• 30% of the aggregate number of shares of our common stock traded during the portion of the normal trading hours on the applicable Accelerated Purchase Date determined in accordance with the Purchase Agreement, which period of time on the applicable Accelerated Purchase Date we refer to as the Additional Accelerated Purchase Period; and

• 300% of the number of purchase shares purchased pursuant to the Regular Purchase corresponding to the Accelerated Purchase effected on such same Accelerated Purchase Date.

The purchase price per share for the shares subject to an Additional Accelerated Purchase will be equal to 97% of the lower of:

• the volume weighted average price of our common stock during the applicable Additional Accelerated Purchase Measurement Period for such Additional Accelerated Purchase; and

• the closing sale price of our common stock on the applicable same Accelerated Purchase Date.

We may, in our sole discretion, submit multiple Additional Accelerated Purchase notices to Lincoln Park prior to 1:00 p.m., eastern time, on a single Accelerated Purchase Date, again provided all shares of common stock subject to all prior Regular Purchases, Accelerated Purchases and Additional Accelerated Purchases, including those prior Accelerated Purchases and Additional Accelerated Purchases effected on the same Accelerated Purchase Date as the applicable Additional Accelerated Purchase, have been properly delivered to Lincoln Park in accordance with the Purchase Agreement prior to such time.

In the case of Regular Purchases, Accelerated Purchases and Additional Accelerated Purchases, the purchase price per share will be equitably adjusted for any reorganization, recapitalization, non-cash dividend, stock split, reverse stock split or other similar transaction occurring during the business days used to compute the purchase price. No Purchase Notices may be delivered at any time when the closing sale price is below $0.10.

Other than as described above, there are no trading volume requirements or restrictions under the Purchase Agreement, and we will control the timing and amount of any sales of our common stock to Lincoln Park.

Suspension Events

Suspension events under the Purchase Agreement include the following:

• the effectiveness of the registration statement of which this prospectus forms a part lapses for any reason (including, without limitation, the issuance of a stop order), or any required prospectus supplement and accompanying prospectus are unavailable for the resale by Lincoln Park of our common stock offered hereby, and such lapse or unavailability continues for a period of 10 consecutive business days or for more than an aggregate of 30 business days in any 365-day period;

• suspension by our principal market of our common stock from trading for a period of one business day;

• the delisting of our common stock from the OTCQX operated by OTC Markets Group, Inc., our principal market, provided our common stock is not immediately thereafter trading on The Nasdaq Capital Market, The Nasdaq Global Market, The Nasdaq Global Select Market, the New York Stock Exchange, the NYSE American, the NYSE Arca, or the OTCQB (or any nationally recognized successor to any of the foregoing);

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• the failure of our transfer agent to issue to Lincoln Park shares of our common stock within two business days after the applicable date on which Lincoln Park is entitled to receive such shares of our common stock;

• any breach of the representations or warranties or covenants contained in the Purchase Agreement or Registration Rights Agreement that has or could have a material adverse effect on us and, in the case of a breach of a covenant that is reasonably curable, that is not cured within five business days;

• any voluntary or involuntary participation or threatened participation in insolvency or bankruptcy proceedings by or against us;

• if at any time we are not eligible to transfer our common stock electronically; or

• if at any time Lincoln Park’s broker is unable to accept shares of our common stock for deposit for reasons not within Lincoln Park’s control.

Following the Commencement Date, Lincoln Park does not have the right to terminate the Purchase Agreement upon any of the suspension events set forth above, although the Purchase Agreement would automatically terminate in the event of any voluntary or involuntary participation or threatened participation in insolvency or bankruptcy proceedings by or against us that are not discharged within 90 days. So long as a suspension event has occurred and is continuing, or if any event which, after notice and/or lapse of time, would reasonably be expected to become a suspension event has occurred and is continuing, we may not direct Lincoln Park to purchase any shares of our common stock under the Purchase Agreement.

Our Termination Rights

We have the unconditional right, at any time, for any reason and without any payment or liability to us, to terminate the Purchase Agreement following the Commencement Date upon one business day’s prior written notice to Lincoln Park. In the event of any voluntary or involuntary bankruptcy proceedings by or against us that are not discharged within 90 days, the Purchase Agreement would automatically terminate without any action by us or Lincoln Park. No termination of the Purchase Agreement will be effective during the pendency of any Regular Purchase, Accelerated Purchase or Additional Accelerated Purchase that has not then fully settled in accordance with the Purchase Agreement.

No Short-Selling or Hedging by Lincoln Park

Lincoln Park has represented to us that at no time prior to the time of execution of the Purchase Agreement has Lincoln Park or its agents, representatives or affiliates engaged in or effected, in any manner whatsoever, directly or indirectly, any short sale (as such term is defined in Rule 200 of Regulation SHO under the Exchange Act) of our common stock or any hedging transaction, which establishes a net short position with respect to our common stock. Lincoln Park agreed that during the term of the Purchase Agreement, it, its agents, representatives or affiliates will not enter into or effect, directly or indirectly, any of the foregoing transactions.

Prohibitions on Certain Substantially Similar Transactions

There are no restrictions on future financings, rights of first refusal, participation rights, penalties or liquidated damages in the Purchase Agreement or Registration Rights Agreement, except we are prohibited (with certain specified exceptions set forth in the Purchase Agreement) from effecting or entering into an agreement to effect an “equity line of credit” or other substantially similar offering whereby an investor is irrevocably bound to purchase securities over a period of time from us at a price based on the market price of our common stock at the time of each such purchase.

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Effect of Performance of the Purchase Agreement on Our Stockholders

All of the shares of our common stock being registered for resale hereunder which have been or may be issued or sold by us to Lincoln Park under the Purchase Agreement are expected to be freely tradable. It is anticipated that shares registered in this offering will be sold from time to time over a period of up to 24-months commencing on the date that the registration statement of which this prospectus forms a part becomes effective, provided that all other conditions set forth in the Purchase Agreement have been satisfied. The sale by Lincoln Park of a significant number of shares of our common stock registered in this offering at any given time could cause the market price of our common stock to decline and to be highly volatile. Sales of our common stock to Lincoln Park, if any, will depend upon market conditions and other factors to be determined by us. We may ultimately decide to sell to Lincoln Park all, some or none of the additional shares of our common stock that may be available for us to sell pursuant to the Purchase Agreement. If and when we do sell additional shares of our common stock to Lincoln Park, after Lincoln Park has acquired the shares of our common stock, Lincoln Park may resell all, some or none of those shares of our common stock at any time or from time to time in its discretion. Therefore, sales to Lincoln Park by us under the Purchase Agreement may result in substantial dilution to the interests of other holders of our common stock. In addition, if we sell a substantial number of shares of our common stock to Lincoln Park under the Purchase Agreement, or if investors expect that we will do so, the actual sales of shares of our common stock or the mere existence of our arrangement with Lincoln Park may make it more difficult for us to sell equity or equity-related securities in the future at a time and at a price that we might otherwise wish to effect such sales. However, we have the right to control the timing and amount of any additional sales of our common stock to Lincoln Park and the Purchase Agreement may be terminated by us at any time at our discretion without any cost to us.

Pursuant to the terms of the Purchase Agreement, from and after Commencement, we have the right, but not the obligation, from time to time to direct Lincoln Park to purchase up to $25 million of our common stock. Depending on the price per share at which we sell our common stock to Lincoln Park pursuant to the Purchase Agreement, we may need to sell to Lincoln Park under the Purchase Agreement more shares of our common stock than are being offered under this prospectus in order to receive aggregate gross proceeds equal to the $25 million total commitment available to us under the Purchase Agreement. If we choose to do so, we must first register for resale under the Securities Act such additional shares of our common stock, which could cause additional substantial dilution to our stockholders. The number of shares of our common stock ultimately offered for resale by Lincoln Park under this prospectus is dependent upon the number of shares of our common stock we direct Lincoln Park to purchase under the Purchase Agreement.

The following table sets forth the amount of gross proceeds we would receive from Lincoln Park from our sale of common stock to Lincoln Park under the Purchase Agreement at varying purchase prices:

Assumed Average Purchase Price Per Share			Number of Registered Shares of our Common Stock to be Issued if Full Purchase ⁽¹⁾		Percentage of Outstanding Shares of our Common Stock After Giving Effect to the Issuance to Lincoln Park ⁽²⁾			Gross Proceeds from the Sale of Shares of our Common Stock to Lincoln Park Under the Purchase Agreement ⁽¹⁾

$	0.25			32,467,532		11.83%	%	$	8,116,883
$	0.50			32,467,532		11.83%	%	$	16,233,766
$	0.77	⁽³⁾		32,467,532		11.83%	%	$	25,000,000
$	1.00			25,000,000		9.36%	%	$	25,000,000
$	1.25			20,000,000		7.63%	%	$	25,000,000

(1)

Although the Purchase Agreement provides that we may sell up to $25 million of our common stock to Lincoln Park, we are registering 32,914,599 shares of our common stock for resale under this prospectus, including 447,067 Commitment Shares that we have issued or will issue to Lincoln Park as a fee for making its irrevocable commitment to purchase our common stock under the Purchase Agreement (for which we have not and will not receive any cash consideration), which may or may not cover all the shares of our common stock we ultimately sell to Lincoln Park under the Purchase Agreement, depending on the purchase price per share. Accordingly, the gross proceeds reflected in the rightmost column are calculated by multiplying only the shares of common stock in the second column in from the left that may be issued and sold by us to Lincoln Park in the future as Purchase Shares under the Purchase Agreement that are being registered under the Securities Act for resale by Lincoln Park in the registration statement that includes this prospectus, by the assumed average price per share set forth in the first column on the left, because we have not and will not receive any cash consideration for the 447,067 shares of common stock that we issued or will issue to Lincoln Park as Commitment Shares. The number of registered shares of common stock to be issued reflected in the table does not give effect to the limitations on the amount of shares we may be permitted to issue to Lincoln Park from time to time under the Purchase Agreement as a result of the Beneficial Ownership Cap.

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	(2)	The denominator will be based on 241,973,011 shares of our common stock outstanding as of May 1, 2026 (including the 447,067 Commitment Shares), adjusted to include the shares of our common stock listed in the second column from the left that we would have sold to Lincoln Park as Purchase Shares pursuant to the Purchase Agreement, assuming such Purchase Shares are sold to Lincoln Park at the assumed average purchase price per share set forth in the first column on the left. The numerator will be based on the number of shares of our common stock issuable under the Purchase Agreement at the corresponding assumed average purchase price per share set forth in the first column on the left, without giving effect to the Beneficial Ownership Cap.

	(3)	The closing sale price per share of our common stock on May 1, 2026

USE OF PROCEEDS

This prospectus relates to shares of our common stock that may be offered and sold from time to time by Lincoln Park. See “Plan of Distribution” elsewhere in this prospectus for more information. We are not selling any securities under this prospectus and we will not receive any proceeds from the sale of shares by Lincoln Park under this prospectus.

We may receive up to $25 million in aggregate gross proceeds from sales of shares of our common stock we make to Lincoln Park under the Purchase Agreement. We may choose to sell fewer than $25 million in shares of our common stock, or, due to the Beneficial Ownership Cap, we may not be able to sell all $25 million in shares of our common stock under the Purchase Agreement, in which case we would raise less than $25 million in aggregate gross proceeds under the Purchase Agreement. It is also possible that we do not sell any shares under the Purchase Agreement.

We will have broad discretion in the use of the net proceeds from any sale of shares of our common stock to Lincoln Park under the Purchase Agreement. Based upon our current plans and business conditions, we intend to use net proceeds from such sales for working capital and general corporate purposes, which include, but are not limited to, research and development expenses and general and administrative expenses. We have not determined the amount of net proceeds to be used specifically for such purposes. The amounts and timing of our actual expenditures may vary significantly and will depend on numerous factors, including market conditions, cash generated or used by our operations, business developments and opportunities that may arise. We may find it necessary or advisable to use portions of the proceeds we receive from our sale of shares of common stock to Lincoln Park under the Purchase Agreement for other purposes. Pending the use of any net proceeds, we expect to invest the net proceeds in interest-bearing, marketable securities.

We will bear all of the costs, fees and expenses incurred in effecting the registration of the shares covered by this prospectus, including, without limitation, the registration and filing fees, printing fees, and fees and expenses of our counsel and our accountants, but all selling and other expenses incurred by the selling stockholder will be paid by the selling stockholder.

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MARKET FOR COMMON STOCK AND DIVIDEND POLICY

Our common stock is traded on the OTCQX under the symbol “VXRT.” The last reported sale price of our common stock on May 7, 2026 on the OTCQX was $0.74 per share. As of May 1, 2026, there were 1,355 stockholders of record of our common stock, one of which was Cede & Co., a nominee for Depository Trust Company (“DTC”). The actual number of stockholders is greater than this number of holders of record and includes stockholders who are beneficial owners, but whose shares are held in “street name” by brokerage firms, banks and other financial institutions or nominees.

We have never declared or paid any cash dividend on our common stock. We intend to retain any future earnings and do not expect to pay dividends in the foreseeable future.

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DESCRIPTION OF BUSINESS

Overview

Vaxart Biosciences, Inc. was originally incorporated in California under the name West Coast Biologicals, Inc. in March 2004 and changed its name to Vaxart, Inc. (“Private Vaxart”) in July 2007, when it reincorporated in the state of Delaware.

We are developing prophylactic vaccine candidates that target a range of infectious diseases, including norovirus (a widespread cause of acute gastroenteritis), coronavirus, including SARS-CoV-2 (the virus that causes coronavirus disease 2019 (“COVID-19”)), and influenza. In addition, we have generated preclinical data for our first therapeutic vaccine candidate targeting cervical cancer and dysplasia caused by human papillomavirus (“HPV”).

We believe our oral tablet vaccine candidates offer important advantages:

First, they are designed to generate broad and durable immune responses, including systemic, mucosal and T cell responses, which may enhance protection against certain infectious diseases, such as norovirus, COVID-19 and influenza, and may have potential clinical benefit for certain cancers and chronic viral infections, such as those caused by HPV.

Second, our tablet vaccine candidates are designed to provide a more efficient and convenient method of administration, enhance patient acceptance and reduce distribution bottlenecks, which we believe will improve the effectiveness of vaccination campaigns.

Our Tablet Vaccine Platform

Platform Components

Our platform technology employs a vector-based approach and consists of the following components:

●

A vector, which is a virus used as a carrier to deliver DNA coding for vaccine antigens and an adjuvant selected to activate the immune system. Specifically, we use non-replicating adenovirus type 5 (“Ad5”), which delivers the DNA encoding both the antigen and adjuvant to the cells of the small intestine, where the antigen and adjuvant are co-expressed. Over 200 clinical trials conducted by others have used Ad5 for a wide range of applications, and we believe that using the same adenovirus in our tablet vaccine candidates may reduce regulatory risk because it is known to regulatory authorities.

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An antigen, which is a viral or bacterial protein that stimulates an immune response to the targeted pathogen. Our antigens are encoded in the Ad5 DNA rather than being directly included in the vaccine. We use a different antigen for each of our clinical vaccine candidates.

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An adjuvant, which is a substance that enhances the immune-stimulating properties of the vaccine. We use a short section of double-stranded RNA (“dsRNA”) encoded in the Ad5 DNA as an adjuvant. dsRNA is a Toll-like receptor 3 (“TLR3”) agonist and is recognized by the innate immune system as a signal of a viral infection and thereby triggering it to mount an immune response in defense.

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Our proprietary enteric-coated tablet, which is designed to deliver the Ad5 vector to the small intestine.

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How Our Tablet Vaccine Candidates Work

Our tablets are designed to deliver vaccines to the small intestine. The tablets are covered with a protective coating that remains intact in the low-pH environment of the stomach and protects the active ingredient contained in the tablet core from degradation in the stomach. The coating is designed to dissolve in the neutral-pH environment of the small intestine. The tablets disintegrate, and the vaccine is released into the small intestine where it can reach and enter the mucosal cells lining the intestine. Once inside the mucosal cells, the Ad5 vector instructs the cells to manufacture antigen protein and adjuvant. The adjuvant is always produced within the exact same intestinal cells that also produce the antigen, so that no excess adjuvant is produced, resulting in enhanced safety. Importantly, the production of antigens in our approach closely mimics the process of actual infection by a pathogenic virus. In addition, we believe that delivering the replication-incompetent Ad5-vectored vaccine via tablet directly to the gut avoids neutralization by systemic immunity.

The Significance of Mucosal Immunity and T Cell Responses

The immune system has developed defenses against pathogens by creating special classes of immune effectors, such as mucosal antibodies directed to wet surfaces and killer T cells that can kill pathogen-infected cells. Most vaccines available today have been developed primarily to elicit blood circulating, or systemic B cell responses, such as serum antibodies. However, there remain many infections, such as norovirus, for which no approved or marketed vaccines exist. These infections and other pathogens may need greater immune responses outside of serum antibodies. These infections largely evade the serum antibody immune response because the pathogen can infect cells that line the mucosal membranes without coming into direct contact with blood.

One of the key benefits of our technology is delivery to the gastrointestinal tract, enabling the vaccine to directly enter the mucosal surface of the intestine and activate the immune system of the gut. Mucosal vaccine delivery is believed to enhance protection against mucosal pathogens by generating immunity at the surface where such pathogens invade. Our tablet vaccine candidates target the mucosal immune cells with a vector-based approach and are designed to create a more potent cytotoxic T cell response and mucosal antibody response, which may provide more effective immunity for certain diseases. Further, we have demonstrated that our vaccine delivered to the intestine can produce mucosal responses at sites distal to the intestine such as the nose and the mouth.

Oral Non-Replicating Ad5 Vector is Designed to Circumvent Anti-Vector Issues

Injected Ad5 vectored vaccines generate strong anti-Ad5 responses, with up to a 100-fold increase in the anti-Ad5 neutralizing antibody titers. In contrast, our oral Ad5 vectored vaccine is designed to circumvent the complications related to anti-Ad5 immunity, allowing the platform to be used for multiple vaccines and repeat annual and booster vaccinations.

Our Product Pipeline

The following table outlines the status of our oral vaccine development programs:

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Our Norovirus Program

Market Overview

Norovirus is the leading cause of vomiting and diarrhea from acute gastroenteritis among people of all ages in the U.S. Each year, on average, norovirus causes 19 to 21 million cases of acute gastroenteritis and contributes to 109,000 hospitalizations and 900 deaths, mostly among young children and older adults. In the U.S., we believe a norovirus vaccine would be beneficial for high-risk groups such as infants and children up to five years old, older adults and the elderly, as well as for workers in the food and travel industries, for healthcare, childcare and elder care workers, first responders, the military, and travelers. In a study published by Johns Hopkins University and the Centers for Disease Control and Prevention (“CDC”) in 2016, the total global annual economic burden of norovirus was estimated at $60 billion. In a more recent health economic study published in the Journal of Infectious Diseases in July 2020, the economic impact to the U.S. was estimated to be $10.6 billion annually. There are currently no approved vaccines or therapies to prevent or treat norovirus infection.

Our Norovirus Vaccine Candidate

We are developing a VP1-based bivalent oral tablet vaccine candidate that would protect against norovirus GI and norovirus GII, the two major norovirus genogroups affecting humans, by targeting the norovirus GI.1 Norwalk strain and the norovirus GII.4 Sydney strain. Because norovirus is an enteric pathogen that infects epithelial cells of the small intestine, we believe that a vaccine that produces antibodies against norovirus locally in the intestine, such as our tablet vaccine candidate which is delivered directly to the gut, may induce optimal protection against infection.

In September 2023, we announced that our Phase 2 GI.1 norovirus challenge study evaluating the safety, immunogenicity, and clinical efficacy of the GI.1 component of our first-generation bivalent norovirus vaccine candidate met five of six primary endpoints based on preliminary topline data. The study achieved its primary endpoints of a statistically significant 29% relative reduction in the rate of norovirus infection between the vaccinated and placebo arms, a strong induction of norovirus-specific immunoglobulin A (IgA) and immunoglobulin G (IgG) antibodies, and other immune response endpoints.

Vaccination also led to a 21% relative reduction in norovirus acute gastroenteritis in the vaccine arm compared to placebo, but this was not statistically significant. In prespecified analyses, the study also showed an 85% relative decrease in viral shedding in the vaccine arm compared with placebo and no statistically significant difference in disease severity in the vaccinated cohort compared with placebo. The vaccine candidate was also safe and well tolerated with no vaccine-related serious adverse events.

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Based on our norovirus clinical data findings to date, our norovirus oral vaccination induces mucosal and systemic immune responses. Norovirus oral vaccination reduced shedding and infection in a rigorous human challenge model. Based on our machine learning and evaluation of more than 13 different immune parameters, norovirus vaccination protection most tightly associates with making a functional antibody response to norovirus in the serum (“NBAA”) and norovirus specific fecal IgA antibodies. Because of the strong induction of mucosal IgA due to the oral vaccination and potential read through into the serum, we believe that this likely means that a functional fecal IgA response is probably critical for protection against norovirus infection.

In the second half of 2024, we received constructive feedback from the U.S. Food and Drug Administration (“FDA”) on our data for potential correlates of protection and next steps for our norovirus program. While we believe we have identified a functional antibody response that may be associated with protection for norovirus, the FDA requested new clinical data before proceeding with further review of our potential correlate.

In 2024, we also created new, second-generation norovirus GI.1 and GII.4 constructs. In preclinical studies, the second-generation norovirus GI.1 and GII.4 constructs appear to be more potent than the first-generation norovirus constructs we previously evaluated in clinical trials. Our expectation is that these second-generation norovirus constructs would also be more potent in humans.

With advice from advisors and infectious disease experts, we decided to proceed with a Phase 1, open label, dose ranging clinical trial evaluating our second-generation oral norovirus vaccine constructs head-to-head against our first-generation constructs. The trial measured safety and immunogenicity, including immune parameters that have correlated to protection in our Phase 2 GI.1 norovirus challenge study.

In June 2025, we reported positive topline results from the Phase 1 clinical trial (Study VXA-109) evaluating our second-generation bivalent norovirus vaccine constructs head-to-head against our first-generation bivalent norovirus vaccine constructs. The open-label, Phase 1 trial was conducted in 60 healthy volunteers who were randomized to receive the first-generation vaccine constructs, an equivalent dose of the second-generation GI.1 and GII.4 vaccine constructs, or a lower dose of the second-generation vaccine constructs (n=20 for each group). The primary immunological endpoint was norovirus blocking antibody assay (NBAA) titer at Day 0 and Day 28. In a Phase 2 challenge study of the first-generation vaccine constructs, these functional NBAA titers were identified as correlates of protection against norovirus infection. Although the study was not powered to determine superiority by statistical methods, the increase in NBAA titers with the second-generation vaccine candidates was sufficiently large (141% for the GI.1 vaccine candidate and 94% for the GII.4 vaccine candidate) to demonstrate statistical significance at the equivalent dose. Further support for the second-generation bivalent norovirus vaccine was provided by the fecal IgA data from the VXA-109 Study. The data showed a 25-fold increase in the GII.4 fecal IgA response and a 10-fold increase in the GI.1 fecal IgA response over baseline with the high dose of the second-generation vaccine candidates after a single tablet administration for each strain. The data also showed an 8-fold increase in the GII.4 fecal IgA response and a 7-fold increase in the GI.1 fecal IgA response over baseline with the low dose of the second-generation vaccine candidates after a single tablet administration for each strain. While the Phase 1 study was not powered to determine superiority by statistical methods, the fecal IgA increases observed with the second-generation constructs compared favorably to the increases observed with the first-generation constructs at the same high dose level and in the same study (13-fold GII.4 and 6-fold GI.1 over baseline).

Following the successful outcome of the VXA-109 trial, the next step, pending a partnership or other funding, would be to advance the program to the next stage of clinical development in 2026.

Pediatric Population. Our current tablet vaccine formulation is designed for delivery to the gut in solid dosage form using an enteric-coated tablet which we believe is the optimal vaccine delivery system for the adult population and children eight years and older. For children six months to seven years in age, we plan to develop minitablet formulations that can deliver the vectored vaccine intact to the gut. Development of our norovirus vaccine in the pediatric population will proceed with a stepdown approach through progressively younger age segments (i.e. 8 to 5 years, 4 to 2 years, 2 years to 6 months).

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Breastfeeding Mothers. In December 2024, we completed a Phase 1 norovirus bivalent vaccine candidate study in partnership with the Bill & Melinda Gates Foundation. The study enrolled 76 healthy, lactating post-partum, women volunteers, to determine the impact of our norovirus vaccine on breast milk norovirus-specific IgA and its potential presence, post-breastfeeding, within infant fecal samples. The study was a randomized, double-blinded, and placebo controlled study to evaluate the safety, tolerability, and immunogenicity of the placebo cohorts and two vaccine cohorts: medium dose (1×10¹¹ IU) and high dose (2×10¹¹ IU). Passive transfer of antibodies from mother to infant that are induced in milk may protect breastfeeding infants from infectious pathogens. We initiated this study in the fourth quarter of 2023 and announced positive top line results in April 2024. Top line results showed antibodies rose in lactating mothers who received the high dose of our bivalent vaccine candidate. Specifically, serum antibodies to norovirus rose on average 5.6 fold in response to the GI.1 virus strain and 4.4 fold in response to the GII.4 virus strain and breast milk antibodies to norovirus rose on average 4.0 fold in response to the GI.1 virus strain and 6.0 fold in response to the GII.4 virus strain. The vaccine was well tolerated with no vaccine-related serious adverse events and no dose-limiting pharmacotoxicity. Infant stool samples contained antibodies to norovirus that correlated with levels in the paired mother’s breast milk, suggesting efficient passive transfer occurred. As a grant recipient from the Bill & Melinda Gates Foundation, Vaxart has agreed to a global access commitment for use of its bivalent norovirus vaccine candidate, if proven effective and approved, in breastfeeding mothers from low- and middle-income countries.

Our COVID-19 Program

Market Overview

Coronaviruses comprise a group of respiratory viruses, encompassing SARS-CoV-1, SARS-CoV-2, and Middle East respiratory syndrome coronavirus (MERS-CoV), among various others. SARS-CoV-2, the virus responsible for COVID-19, induces a severe respiratory tract infection and stands as a significant cause of hospitalization and mortality globally. Currently approved COVID-19 vaccines seem to have varying levels of efficacy to emerging strains of SARS-CoV-2.

Our COVID-19 Vaccine Candidates

We have spent significant effort developing COVID-19 vaccine candidates over the past few years. One of our first COVID-19 vaccine candidates (rAd-S, known as Vaxart clinical candidate VXA-CoV2-1.1-S) expressed only the spike (“S”) protein from the SARS-CoV-2 Wuhan strain. In September 2022, we announced the results from the first part of a two-part Phase 2 clinical study evaluating the safety and immunogenicity of VXA-CoV2-1.1-S met both its primary and secondary endpoints based on topline data. VXA-CoV2-1.1-S was able to boost the serum antibody responses for volunteers that previously received an mRNA vaccine (either Pfizer/BioNTech or Moderna). Serum neutralizing antibody responses to SARS-CoV-2 (Wuhan), a recognized correlate of protection, were boosted in this population from a geometric mean of 481 to 778, a fold rise of 1.6. Volunteers that had lower starting titers had larger increases than subjects that had higher titers. There were also substantial increases in the neutralizing antibody responses to the SARS-CoV-2 Omicron BA4/5 in these volunteers as measured by sVNT assay. Increases in the mucosal IgA antibody responses (antibodies in the nose and mouth) were observed in approximately 50% of subjects. Subjects that had an increase in the mucosal IgA response to SARS-CoV-2 Wuhan S had an increase in IgA responses to other coronaviruses including SARS-CoV-2 Omicron BA4/5, SARS-CoV-1, and MERS-CoV, demonstrating the cross-reactive nature of these immune readouts. We are not proceeding with the second part of the study.

We have also made a COVID-19 vaccine candidate that expresses only the S protein from the SARS-CoV-2 XBB strain as well as a COVID-19 vaccine candidate that expresses the S protein from the SARS-CoV-2 KP.2 strain. Based on preclinical data, our XBB COVID-19 vaccine candidate is more potent than our prior COVID-19 vaccine constructs.

In January 2024, we were awarded a contract by the U.S. Biomedical Advanced Research and Development Authority (“BARDA”), a division of the Administration for Strategic Preparedness and Response (“ASPR”) within the U.S. Department of Health and Human Services (“HHS”), for $9.3 million to fund preparation for a Phase 2b clinical study involving 10,000 patients. Vaxart executed on the deliverables and received all $9.3 million of cash payments related to this contract in 2024. BARDA and Vaxart have closed out this contract.

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In June 2024, we entered into an agreement (as modified or amended from time to time, the “2024 ATI-RRPV Contract”) with Advanced Technology International (“ATI”), the Rapid Response Partnership Vehicle’s Consortium Management Firm funded by BARDA. Under the 2024 ATI-RRPV Contract, we may receive up to $460.7 million to conduct the Phase 2b study, manufacture a COVID-19 vaccine candidate targeting the KP.2 strain, and acquire an approved mRNA vaccine targeting the KP.2 strain. However, funding has been released incrementally based on modifications to the 2024 ATI-RRPV Contract as certain milestones are attained. Pursuant to Modification No. 6 to the 2024 ATI-RRPV Contract, dated March 10, 2026, the total amount of funding available for payment under the 2024 ATI-RRPV Contract is approximately $316.0 million.

The Phase 2b study is a double-blind, multi-center, randomized, comparator-controlled study to determine the relative efficacy, safety, and immunogenicity of Vaxart’s oral pill COVID-19 vaccine candidate against an approved mRNA COVID-19 injectable vaccine in adults previously immunized against COVID-19 infection. The study design anticipates enrolling approximately 10,400 healthy adults 18 years and older in the U.S. with approximately 5,200 receiving our COVID-19 vaccine candidate and approximately 5,200 receiving an approved mRNA comparator. The study strives to enroll participants in line with U.S. demographics, as well as including at least 25% over the age of 65.

The Phase 2b study will measure comparative efficacy for symptomatic and asymptomatic disease, systemic and mucosal immune induction, and the incidence of adverse events. The primary endpoint is relative efficacy of Vaxart’s COVID-19 vaccine candidate compared to an approved mRNA comparator for the prevention of symptomatic disease. Primary efficacy analysis will be performed when all participants have either discontinued or completed a study visit 12 months post-vaccination.

In the second half of 2024, we initiated and completed enrollment of the sentinel cohort of the Phase 2b study consisting of 400 participants comparing our XBB COVID-19 vaccine candidate against an approved mRNA XBB comparator. In January 2025, an independent data safety monitoring board (“DSMB”) recommended the study to proceed without modifications based on initial safety assessment of 30-day data from the sentinel cohort. Additional data regarding the 12-month follow-up for these 400 individuals is anticipated to be shared in the first half of 2026.

In February 2025, we received written notification from ATI in the form of a stop work order (the “February 2025 SWO”) directing the Company to stop work on the 2024 ATI-RRPV Contract, with the exception that we could continue efforts associated with the per protocol follow-up for the 400-participant sentinel cohort. The February 2025 SWO was to be in effect for a period of 90 days. Subsequently, in April 2025, the Company received written notification from ATI in the form of a stop work order lift (the “Lift Notice”) that the February 2025 SWO had been lifted and that the Company may resume incurring costs, participating in meetings, and communicating with the Government and ATI concerning the project award.

In May 2025, following additional discussion between the Company and HHS BARDA regarding costs, timelines, and regulatory pathway, we received approval from HHS BARDA to initiate dosing. We subsequently proceeded to dose patients in the 10,000-participant portion of the Phase 2b clinical study.

In August 2025, the Company received written notification from ATI in the form of a second stop work order (the “August 2025 SWO”) directing the Company to stop work on screening and enrollment for the 10,000-person cohort of the Phase 2b clinical study. The Company was, however, permitted to continue efforts associated with the per protocol follow-up to the extent study participants were already dosed. As of the notification date, the Company had enrolled approximately half of the targeted number of participants for the study.

On October 8, 2025, the Company received another notice (the “Follow-Up Notice”) from ATI, clarifying the scope of the August 2025 SWO and therefore the 2024 ATI-RRPV Contract. The Follow-Up Notice definitively confirmed that BARDA intends to stop all ongoing enrollment under the 2024 ATI-RRPV Contract but allows efforts in support of participants already enrolled in the study, who will continue to be followed, including planned analyses of the sentinel cohort as well as the enrolled main study population.

On March 10, 2026, the Company entered into Modification No. 6 to the 2024 ATI-RRPV Contract. Pursuant to Modification No. 6 to the 2024 ATI-RRPV Contract, pursuant to which the total amount of funding available for payment under the 2024 ATI-RRPV Contract was increased to $316.0 million. The Company anticipates a further modification to the 2024 ATI-RRPV Contract that will reflect the reduced scope of work and corresponding reduction in funding that resulted from previously issued stop work orders.

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As of the filing date of this prospectus, we anticipate that the Phase 2b study, which enrolled healthy adults 18 years and older in the U.S. with 400 participants from the sentinel cohort and approximately 5,000 participants enrolled from the main cohort as of our receipt of the August 2025 SWO, will continue to collect participant data over a 12 month period post-vaccination and will continue to be funded under the 2024 ATI-RRPV Contract. Out of the approximately 5,400 total participants, we expect approximately 2,700 to have received our COVID-19 vaccine candidate and approximately 2,700 to have received an approved strain-matched mRNA comparator. Primary efficacy analysis will be performed when all participants have either discontinued or completed a study visit 12 months post-vaccination.

Our Influenza Program

Market Overview

Influenza is one of the most common global infectious diseases, causing mild to life-threatening illness with symptoms such as sore throat, nasal discharge, fever, and even death. It is estimated that there are around one billion cases of seasonal influenza annually worldwide, of which 3 million to 5 million cases are considered severe, causing 290,000 to 650,000 deaths per year globally. Very young children and the elderly are at greatest risk from death. In the U.S., between 9,000,000 and 41,000,000 people catch influenza annually, between 140,000 and 710,000 people are hospitalized with complications of influenza, and between 12,000 and 52,000 people die from influenza and its complications each year.

The CDC generally recommends that individuals six months and older be vaccinated annually against influenza. In the U.S., this means an influenza vaccination is recommended for more than 300 million people.

Our Seasonal Influenza Vaccine Candidate

We are developing a tablet vaccine candidate for the immunization of healthy adults against seasonal influenza. Commercial seasonal influenza vaccines today are composed of either three (trivalent) or four (quadrivalent) strains, either one influenza B and two influenza A strains, or two of each. Our seasonal influenza vaccine candidate is a trivalent seasonal influenza vaccine consisting of two circulating influenza A lineage viruses (H1N1 and H3N2) as well as one circulating influenza B lineage virus (B/Victoria lineage), matching the seasonally updated recommendations by the World Health Organization. We envision formulating our tablet vaccine candidate as one tablet per strain, or three tablets in total for the trivalent vaccine. We believe this modularity will allow for enhanced flexibility. For instance, in the event of a late season strain change, the tablet containing the obsolete strain could be easily replaced without having to discard the two correctly matched vaccine tablets. We will also consider formulating all three strains into a single tablet. This format would be the simplest to administer but would take away some of the flexibility advantages that separate tablets would afford. We will assess the final formulation of our tablet vaccine candidates after conducting market studies to evaluate market acceptance closer to commercialization.

Seasonal Influenza Clinical Trials

To date, we have completed two Phase 1 trials and have conducted the active portion of a Phase 2 challenge trial of our H1N1 influenza vaccine candidate. We have also completed a Phase 1 trial of an influenza B vaccine candidate (B Yamagata lineage).

H1N1 Influenza Phase 2 Challenge Study Funded by HHS BARDA

In 2015, we were awarded a $13.9 million contract by BARDA, part of the HHS. This two-year contract was awarded under a Broad Agency Announcement issued to support the advanced development of more effective influenza vaccines to improve seasonal and pandemic influenza preparedness. The contract primarily funded a Phase 2 challenge study in human volunteers, designed to evaluate whether our H1N1 tablet vaccine candidate offers broader and more durable protection than currently marketed injectable vaccines. The contract with HHS BARDA was subsequently increased to $15.7 million and the term was extended until September 2018.

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In this Phase 2 study, volunteers were randomized into three groups. One group received our oral H1N1 influenza tablet vaccine candidate, a second group received a commercially licensed inactivated influenza vaccine by intramuscular injection, and a third group received placebo. Three months following immunization, volunteers were challenged (deliberate experimental administration) with live H1N1 (A/H1N1 pdm09) influenza virus by intranasal administration. The placebo group served as the control group to determine how many unvaccinated volunteers became infected and how severe their influenza symptoms became. Data from our vaccine candidate group and the commercially licensed inactivated vaccine group were compared to placebo to determine each vaccine’s efficacy in this challenge study. Importantly, the two vaccines were also compared head-to-head. The goal of the study was to compare the efficacy of our vaccine to protect volunteers from illness caused by H1N1 influenza challenge, compared to both the injectable vaccine and placebo three months after immunization.

Clinical Trial Results VXA-CHAL-201

The Phase 2 challenge study was enrolled during 2016 and 2017. During this time, 179 subjects that cleared the screening requirements were randomized to receive a single dose of our tablet vaccine, the commercial injectable vaccine, or placebo. Of these 179 subjects, 143 subjects were subsequently challenged with live H1N1 influenza virus 90 to 120 days after dosing.

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Safety. The side effects of the vaccines and placebo in the first seven days following administration were generally mild. In the first seven days following administration, the solicited adverse events reported in the vaccine and placebo groups were mostly grade 1 in severity, and none were above grade 2. The most frequent solicited adverse event was headache in our tablet vaccine group (7%), injection site tenderness in the commercially licensed inactivated vaccine group (26%) and headache in the placebo group (19%). There were no serious adverse events and no new onsets of chronic illnesses related to our vaccine adjuvant recorded during the follow up period of the study.

Efficacy – Reduction of PCR Confirmed Influenza Illness.

The primary efficacy objective was to determine vaccine efficacy of our tablet vaccine following the challenge with the wild-type influenza A H1 virus strain (A/H1N1 pdm09). The primary efficacy endpoint was illness. The illness rate was 29% for our tablet vaccine, 35% for the commercial inactivated influenza vaccine, and 48% for subjects in the placebo group. Our tablet vaccine had a lower rate of illness than the commercial vaccine (-6% difference in illness rate in favor of our vaccine), although given the small size of the study, these differences were not statistically significant. Similarly, the difference in illness rates between our tablet vaccine and placebo (-19.1%) and the commercial injected vaccine and placebo (-13.2%) trended toward protection but were not statistically significant. These results suggest that our vaccine is no worse, and trended better than the commercial vaccine for protection. These results are summarized in Table 2 below.

Table 2. H1 Influenza Phase 2 Challenge Study: Illness Rates*.

VAXART

Commercial

VAXART-

Commercial

Placebo

% (95% CI)

Rate Difference (95% CI)

% (95% CI)

29.3 (18.1, 42.7)

35.2 (22.7, 49.4)

-5.9 (-24.3, 12.5)

48.4 (30.2, 66.9)

*Illness was defined as a combination of symptoms reported on a patient reported outcome tool (Flu-PRO^TM) and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) detectable shed influenza virus.

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Efficacy – Shedding

Shedding represents influenza virus that is detected in nasal swabs post infection and is representative of viral infection and replication. In the study, 44.8% of subjects in VXA-A1.1 had at least one day positive for shedding, versus the commercial injected vaccine where 53.7% were positive for shedding and where 71.0% of placebo subjects were positive for shedding. There were no statistically significant differences observed between our tablet vaccine and the commercial inactivated influenza vaccine for viral shedding area under the curve (“AUC”). However, AUC was calculated using a standard logarithmic trapezoidal method and included only detectable shedding during the first five days of the duration of shedding, with subjects removed from the analysis that didn’t shed influenza for five days (a zero value cannot be used in log calculations and integrated). This may have led to an underestimate of the effect on viral shedding for the two vaccines relative to placebo. Therefore, in order to better determine the effect of the vaccines on shedding, an alternative method was used in which volunteers were defined as infected if they had detectable viral shedding at any time 36 hours after challenge. This approach eliminated possible issues related to calculations (log calculations of zero values) and of large doses of challenge virus (first 36 hours might be pass through rather than replicating influenza). In a Bayesian analysis, both vaccines significantly reduced the probability of shedding relative to placebo (Bayesian posterior p=0.001 for our tablet vaccine and p=0.009 for the commercial inactivated influenza vaccine). There is also trend toward greater efficacy for our vaccine with a posterior probability of approximately 80% (Table 3).

Table 3. H1 Influenza Phase 2 Challenge Study: Infection Rates*.

Treatment Arm	N	Number Infected	Percent (95% CI)	Posterior P
Placebo	31	22	71% (55-85%)	-
Commercial	54	24	44% (32-58%)	0.009
Vaxart Vaccine	58	21	36% (24-49%)	0.001

*Infection was defined as any positive quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) detectable shed influenza virus on any day after 36 hours from viral challenge. In a Bayesian analysis, both vaccines provide a statistically significant protection against infection. There is also trend toward greater efficacy for our vaccine with a posterior probability of approximately 80%.

Phase 1 Trial. Influenza B (Yamagata lineage)

In 2015 and 2016, we conducted a randomized, double-blind, placebo-controlled Phase 1 trial to test the safety and immunogenicity of an influenza B tablet vaccine. A total of 54 healthy adults aged 18 to 49 were enrolled, with 38 receiving the vaccine and 16 receiving placebo. To participate in this trial, subjects were required to have an initial HAI measure of no greater than 1:20. The active phase of the trial was through day 28, with the follow-up phase for monitoring safety to continue for one year. All subjects who received the vaccine received a single dose of either 1 x 10¹⁰ IU or 1 x 10¹¹ IU on Day 0.

Safety. The side effects of the vaccine or placebo in the first seven days following administration were generally mild with no serious adverse events. There were no notable differences between the active dose groups and placebo in safety and tolerability.

HAI. In the placebo group, HAI GMT remained essentially unchanged (1:33) at day 28 post dosing. The GMFR of HAI titers both active treated groups at day 28 post dosing was about 2-fold, and independent of dose. For the vaccinated groups receiving either 1×10¹⁰ IU or 1×10¹¹ IU, seroconversion was observed in 5/19 subjects (26.3%) and 3/19 subjects (15.8%), respectively. There were no seroconversions in the placebo group.

Antibody Secreting Cells (ASCs). In order to measure total antibody responses to HA, the numbers of circulating B cells that recognize influenza HA in peripheral blood were measured by ASC assay on days 0 and 7 after immunization. Results show that ASCs could be reliably measured on day 7 in the vaccine-treated groups. Background ASCs were generally negligible on day 0. By IgG ASC, 68% of 1×10¹⁰ IU dose subjects responded, and 84% of subjects in the 1×10¹¹ IU dose group responded. For the 1×10¹¹ IU dose vaccine treated group, an average of 21 IgA ASCs (95% CI: 7 – 35) and 73 IgG ASCs (95% CI: 35 – 111) each per 1×10⁶ peripheral blood mononuclear cell (PBMC) were found at day 7. For the 1×10¹⁰ IU dose vaccine treated group, an average of 16 IgA ASCs (95% CI: 2 – 29) and 44 IgG ASCs (95% CI: 21 – 66) were found at day 7. The placebo group had no responders, and negligible average number of spots (1 or less) on Day 7 (95% CI: -0.6 – -2).

Next Steps

We continue to advance our avian influenza program. We previously published data demonstrating protection in a preclinical model against avian influenza after oral immunization (Clin Vaccine Immunol 2013). In 2025, we completed a preclinical study with a newly created avian influenza vaccine candidate to cover the latest clade 2.3.4.4b H5N1 avian influenza strain. This vaccine candidate was 100% protective against death in a robust ferret clade 2.3.4.4b challenge model, compared with 0% survival in placebo-treated animals. Vaxart intends to publish the results of this preclinical study in a peer-reviewed publication.

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The Company intends to work with governments around the world to create pandemic monovalent influenza vaccines for emergency use or stockpiling, if requested. We are also continuing development of our preclinical seasonal influenza vaccine candidate.

Our HPV Therapeutic Vaccine Program

HPV is a family of more than 120 viruses which are extremely common globally. At least 13 HPV types are cancer-causing. HPV is primarily transmitted through sexual contact and infection is very prevalent following the onset of sexual activity. Nearly all cases of cervical cancer are attributable to HPV infection, with two HPV types – HPV-16 and HPV-18 – responsible for 70% of cervical cancers and precancerous cervical lesions. Cervical cancer is the fourth most common cancer in women worldwide, and about 13,000 new cases are diagnosed annually in the U.S. according to the National Cervical Cancer Coalition. Studies have indicated a high lifetime probability of any HPV infection by both men and women in the U.S., with some estimates indicating at least 80% of women and men acquire HPV by age 45. The CDC estimates 80 million U.S. citizens are currently infected with HPV, representing 25% of the population, with about 14 million new infections per year.

In women, many HPV infections of the cervix will spontaneously resolve and clear within two to three years, but women who have a persistent infection are at high risk of developing cellular abnormalities known as cervical intraepithelial neoplasia (“CIN”), which can progress to invasive cancer over time. More than 400,000 women are diagnosed with CIN annually in the U.S., with an annual incidence estimate for CIN1 and CIN2/3 at 1.6 and 1.2 per 1,000 women, respectively.

There are currently no approved therapeutic vaccines to treat HPV infection or cancer. Current treatment options for women infected with HPV include monitoring CIN status, surgical procedures to remove affected tissue, and chemotherapeutic or radiation therapies to treat localized or metastatic cervical cancer. Therefore, a medical need remains for a therapeutic vaccine to treat women with HPV-associated CIN and/or cervical cancer.

Our HPV Therapeutic Vaccine Candidate

We are in the early stages of developing a bivalent HPV vaccine against HPV-16 and HPV-18, the strains responsible for approximately 70% of cases of cervical cancer. We plan to target the E6 and E7 gene products of each strain, which are the primary oncogenic proteins responsible for progression through the stages of CIN to invasive cervical cancer. In pre-clinical studies, we have demonstrated immunogenicity for both our HPV-16 and our HPV-18 vaccine candidates. Specifically, mice given our HPV-16 or HPV-18 vaccines induced T cell responses to HPV as measured by IFN gamma ELISPOT. In addition, our HPV-16 vaccine has demonstrated tumor growth suppression as well as increased survival in a robust HPV tumor model in mice.

Next Steps

We will need to make a regulatory filing to proceed with clinical trials for an HPV vaccine candidate. Our clinical plan is to test the vaccine candidate in subjects with cervical dysplasia related to HPV-16 or HPV-18, and to evaluate the ability of the vaccine candidate to clear HPV infection, reduce the cervical dysplasia score, and induce T cells known to be important in the clearance of HPV. The primary endpoint will be safety and the secondary endpoint will be immunogenicity by examining T cell responses. Although clinical responses will be tracked, it is expected that the first study may not be powered to obtain statistically significant efficacy readouts.

Anti-Virals

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Through the 2018 Merger with Aviragen, we acquired two royalty earning products, Relenza and Inavir. We also acquired three Phase 2 clinical stage antiviral compounds, of which we have discontinued independent clinical development. However, for one of these, Vapendavir, we have entered into an exclusive worldwide license agreement with Altesa Biosciences, Inc. (“Altesa”) in July 2021, permitting Altesa to develop and commercialize this capsid-binding broad-spectrum antiviral. In May 2025, Altesa announced positive top line results from its Phase 2 placebo-controlled study examining the effects of Vapendavir in COPD patients challenged with rhinovirus. Altesa subsequently communicated their intention to run a randomized placebo-controlled Phase 2b trial that will enroll 900 COPD patients to examine the safety and efficacy of Vapendavir to treat rhinovirus infections in patients with COPD. In February 2026, Altesa announced a $75 million Series B funding round to support the Phase 2b study.

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Relenza and Inavir are antivirals for the treatment of influenza, marketed by GlaxoSmithKline, plc (“GSK”) and Daiichi Sankyo Company, Limited (“Daiichi Sankyo”), respectively. We have earned royalties on the net sales of Relenza and Inavir in Japan. The last patent for Relenza expired in July 2019 and based on information provided by Daiichi Sankyo, the last patent for Inavir expires in August 2036. Sales of these antivirals vary significantly by quarter, because influenza virus activity displays strong seasonal cycles, and by year depending on the intensity and duration of the flu season, the impact COVID-19 has had, and may continue to have, on seasonal influenza, and competition from other antivirals such as Tamiflu and Xofluza.

Manufacturing

Manufacturing our oral tablet vaccines consists of two main stages, the production of bulk vaccine (drug substance), and the formulation and tableting thereof (drug product). Drug substance manufacturing consists primarily of the production and purification of the active ingredient. Bulk drug substance is then lyophilized, formulated and subsequently tableted and coated using a proprietary formulation and tableting process that we developed.

Bulk Vaccine Manufacturing (Drug Substance)

From inception, we relied on a combination of third-party contract manufacturers and in-house facilities to manufacture clinical cGMP bulk drug substance for our tablet vaccine candidates. Starting in 2017, we invested in developing our own bulk vaccine manufacturing process with the aim to establish a small cGMP bulk manufacturing facility at our corporate headquarters in California for manufacturing cGMP product for our Phase 1 and small Phase 2 trials. We expanded in November 2021 by subleasing another GMP manufacturing facility which we use to perform the same bulk manufacturing processes in-house.

Vaccine Tablet Manufacturing (Drug Product)

From inception we contracted with third-party contract manufacturers for the manufacture, labeling, packaging, storage, and distribution of our drug product. In 2016, we established drug product manufacturing capabilities at our corporate headquarters. Our facility is licensed by the State of California Department of Public Health Food and Drug Branch to manufacture drug product for clinical trials. We have also built a new GMP facility in California for tableting, coating and packaging of our vaccine candidates.

We have limited experience with process development, and the manufacture, testing, quality release, storage and distribution of drug substance and drug product according to cGMP and regulatory filings. The cGMP regulations include requirements relating to the organization of personnel, buildings and facilities, equipment, control of components and drug product containers and closures, production and process controls, packaging and labeling controls, holding and distribution, laboratory controls, records and reports, and returned or salvaged products. Our facilities, and our third-party manufacturers, are subject to periodic inspections by FDA and local authorities, which include, but are not limited to procedures and operations used in the testing and manufacture of our vaccine candidates to assess our compliance with applicable regulations. If we or our third-part manufacturers fail to comply with statutory and regulatory requirements we and they could be subject to possible legal or regulatory action, including warning letters, the seizure or recall of products, injunctions, consent decrees placing significant restrictions on or suspending manufacturing operations and civil and criminal penalties. These actions could have a material adverse impact on the availability of our tablet vaccine candidates. Similar to contract manufacturers, we have in the past encountered difficulties involving production yields, quality control and quality assurance, and if we are not able to produce drug product or drug substance in sufficient quantities our ability to conduct our clinical trials and commercialize our tablet vaccine candidates, if approved, will be impaired.

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Research and Development

In the ordinary course of business, we enter into agreements with third parties, such as clinical research organizations, medical institutions, clinical investigators and contract laboratories, to conduct our clinical trials and aspects of our research and preclinical testing. These third parties provide project management and monitoring services and regulatory consulting and investigative services.

Competition

The pharmaceutical and vaccine industries are characterized by intense competition to develop new technologies and proprietary products. In general, competition among pharmaceutical products is based in part on product efficacy, safety, reliability, availability, price and patent position.

While we believe that our proprietary tablet vaccine candidates provide competitive advantages, we face competition from many different sources, including biotechnology and pharmaceutical companies, and we may also face competition from academic institutions, government agencies, as well as public and private research institutions. Any products that we may commercialize will have to compete with existing products and therapies as well as new products and therapies that may become available in the future.

There are other organizations working to improve existing therapies, vaccines or delivery methods, or to develop new vaccines, therapies or delivery methods for their selected indications. Depending on how successful these efforts are, it is possible they may increase the barriers to adoption and success of our vaccine candidates, if approved.

We anticipate that we will face intense and increasing competition as new vaccines enter the market and advanced technologies become available. We expect any tablet or other oral delivery vaccine candidates that we develop and commercialize to compete on the basis of, among other things, efficacy, safety, convenience of administration and delivery, price, availability of therapeutics, the level of generic competition and the availability of reimbursement from government and other third-party payors.

Our commercial opportunity could be reduced or eliminated if our competitors develop and commercialize products that are safer, more effective, have fewer or less severe side effects, are more convenient or are less expensive than any products that we may develop. Our competitors also may obtain FDA or other regulatory approval for their products more rapidly than we can obtain approval for our vaccine candidates, which could result in our competitors establishing a strong market position before we are able to enter the market. In addition, our ability to compete may be affected in many cases by insurers or other third-party payors seeking to encourage the use of generic products.

We face competition from smaller companies who, like us, rely on investors to fund research and development and compete for co-development and licensing opportunities from large and established pharmaceutical companies. We may also face significant competition in pursuing partnership opportunities and strategic acquisitions from other companies, financial investors and enterprises whose cost of capital may be lower than ours. Competition for future partnerships or asset acquisition opportunities in our markets is intense and we may be forced to increase the price we pay for such assets.

We also depend upon our ability to attract and retain qualified personnel, obtain patent protection or otherwise develop proprietary products or processes and secure sufficient capital resources for the development and commercialization of our products.

Norovirus Vaccine Candidate

As of January 2026, there are no vaccines approved by the FDA or other global regulatory agencies for the prevention of norovirus. We are aware that Moderna, Inc. and Merck, Inc. are developing norovirus vaccines that would be delivered by injection. Other companies reporting development of a norovirus vaccine candidate are Anhui Zhifei Longcom Biopharmaceutical Co. Ltd., Chongqing Zhifei Biological Products Co., Ltd., and the National Vaccine and Serum Institute of China. In addition, we are aware of Cocrystal Pharma, Inc. reporting development of an oral antiviral for norovirus. There may be other development programs that we are not aware of.

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COVID-19 Vaccine Candidate

There is significant competition in the COVID-19 vaccine market. Pfizer-BioNTech’s COVID-19 vaccine, Moderna’s COVID-19 vaccine, and Novavax’s COVID-19 vaccine have been approved in the U.S. and many countries around the world.

Seasonal Influenza Vaccine Candidate

We believe our seasonal influenza vaccine candidate would compete directly with approved vaccines in the market, which include non-recombinant and recombinant products that are administered via injection or intranasally. Major players include AstraZeneca plc, CSL Ltd., Emergent BioSolutions Inc., F. Hoffmann-La Roche AG, GSK PLC, Instituto Butantan, Merck & Co., Inc., Pfizer, Inc., Sanofi S.A., and Sinovac Biotech Ltd. Novel influenza programs are being developed by Centivax, Inc., Emergent BioSolutions, GSK plc, and Moderna, Inc. Antiviral programs targeting influenza are in development or marketed by F. Hoffmann-La Roche AG. and Merck & Co., Inc.

HPV Therapeutic Vaccine Candidate

As of January 2026, there are no therapeutic vaccines approved by the FDA or other global regulatory agencies for the treatment of HPV; however, a number of vaccine manufacturers, academic institutions and other organizations currently have, or have had, programs to develop such a vaccine. We believe that several companies are in various stages of developing an HPV therapeutic vaccine including Inovio Pharmaceuticals, Inc., Genexine Inc., and several others.

Inavir

A number of competing anti-influenza antivirals are marketed in Japan, including Xofluza, Tamiflu, Rapiacta, and Relenza. Xofluza is marketed by Shionogi & Co., Ltd. and currently believed to be the market leader in Japan, substantially reducing the sales of Inavir in Japan by Daiichi Sankyo. This has had a significant negative impact on the royalty payments we have received from Daiichi Sankyo and may continue to have a significant negative impact on our future royalty revenues.

Intellectual Property

We strive to protect and enhance our proprietary technology, inventions and improvements that are commercially important to our business by seeking, maintaining, and defending patent rights. We also rely on trade secrets relating to our platform and on know-how, continuing technological innovation to develop, strengthen and maintain our proprietary position in the vaccine field. In addition, we rely on regulatory protection afforded through data exclusivity, market exclusivity and patent term extensions where available. We also utilize trademark protection for our company name and expect to do so for products and/or services as they are marketed.

Our commercial success will depend in part on our ability to obtain and maintain patent and other proprietary protection for commercially important technology, inventions and know-how related to our business; defend and enforce our patents; preserve the confidentiality of our trade secrets; and operate without infringing the valid enforceable patents and proprietary rights of third parties. Our ability to stop third parties from making, using, selling, offering to sell or importing our tablet vaccine candidates may depend on the extent to which we have rights under valid and enforceable patents or trade secrets that cover these activities. With respect to company-owned intellectual property, we cannot be sure that patents will be granted with respect to any of our pending patent applications or with respect to any patent applications we may file in the future, nor can we be sure that any of our existing patents or any patents that may be granted to us in the future will be commercially useful in protecting our commercial products and methods of manufacturing the same.

We have developed numerous patents and patent applications and own substantial know-how and trade secrets related to our platform and tablet vaccine candidates.

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Vaccine Platform Technology. As of December 31, 2025, we held three U.S. patents with claims relating to our platform technology. Two of these U.S. patents include claims related to our seasonal influenza vaccine candidate. These patents will expire in 2027, or later if patent term extension applies. As of December 31, 2025, we held more than 45 issued foreign patents related to our platform technology and/or our vaccine candidates. These patents will expire in 2027, or later if patent term extension applies.

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Tablet Vaccine Formulation. We own considerable know-how and as of December 31, 2025, held over 25 foreign patents, including in a number of European countries, Canada, Japan, China, South Korea, Singapore, Australia, Russia, Israel, Indonesia, Vietnam, the Eurasian Patent Organization and South Africa. We also have one application pending in the U.S. Patents issuing from these applications will expire in 2035, or later if patent term extension applies.

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COVID-19 Vaccine Candidate. As of December 31, 2025, we have filed a PCT application and have pending applications in the U.S., EPO, Australia, Canada, China, Japan, South Korea, India, and South Africa relating to our COVID-19 vaccine candidate. Any patents issuing from these pending applications will expire in 2041/2042, or later if patent term extension applies.

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Norovirus Vaccine Tablet Candidates. As of December 31, 2025, we have filed a provisional application in the U.S. and held two U.S. patents, and over 20 patents in foreign countries including a number of European countries, Australia, Japan, South Korea, South Africa, The African Regional Intellectual Property Organization (ARIPO), and New Zealand, and have pending applications in the U.S., China, Canada, the EPO, and the Eurasian Patent Organization. Any patents issuing from these applications will expire in 2036, or later if patent term extension applies.

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Influenza Vaccine Candidates. We have been issued 13 foreign patents as of December 31, 2025 relating to our current H1N1 influenza vaccine candidate. These patents will expire in 2030, or later if patent term extension applies.

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As of December 31, 2025, PCT applications relating to improved adenoviral vectors and antibodies to norovirus antigens have been filed.

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Inavir. As of December 31, 2025, we own Japanese patents related to Inavir, which is exclusively licensed to Daiichi Sankyo. Based on information provided by Daiichi Sankyo, the last patent related to Inavir in Japan is set to expire in August 2036, at which time royalty revenue will cease. However, the patent covering the laninamivir octanoate compound expired in 2024, opening the market for generic competition, potentially decreasing or eliminating the royalties received.

In addition to the above, we have established expertise and development capabilities focused in the areas of preclinical research and development, manufacturing and manufacturing process scale-up, quality control, quality assurance, regulatory affairs and clinical trial design and implementation. We believe that our focus and expertise will help us develop products based on our proprietary intellectual property.

The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the date of filing the non-provisional application. In the U.S., a patent’s term may be lengthened by patent term adjustment, which compensates a patentee for administrative delays by the U.S. Patent and Trademark Office in granting a patent, or may be shortened if a patent is terminally disclaimed over an earlier-filed patent.

The term of a patent that covers an FDA-approved drug may also be eligible for patent term extension, which permits patent term restoration of a U.S. patent as compensation for the patent term lost during the FDA regulatory review process. The Hatch-Waxman Act permits a patent term extension of up to five years beyond the expiration of the patent. The length of the patent term extension is related to the length of time the drug is under regulatory review. A patent term extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval and only one patent applicable to an approved drug may be extended. Moreover, a patent can only be extended once, and thus, if a single patent is applicable to multiple products, it can only be extended based on one product. Similar provisions are available in Europe and other foreign jurisdictions to extend the term of a patent that covers an approved drug. When possible, depending upon the length of clinical trials and other factors involved in the filing of a new drug application, or NDA, we expect to apply for patent term extensions for patents covering our vaccine candidates and their methods of use.

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Trade Secrets

We rely, in some circumstances, on trade secrets to protect our technology. However, trade secrets can be difficult to protect. We seek to protect our proprietary technology and processes, in part, by entering into confidentiality agreements with our employees, consultants, scientific advisors and contractors. We also seek to preserve the integrity and confidentiality of our data and trade secrets by maintaining physical security of our premises and physical and electronic security of our information technology systems. While we have confidence in these procedures, agreements or security measures may be breached, and we may not have adequate remedies for any breach. In addition, our trade secrets may otherwise become known or be independently discovered by competitors. To the extent that our consultants, contractors or collaborators use intellectual property owned by others in their work for us, disputes may arise as to the rights in related or resulting know-how and inventions.

Government Regulation and Product Approval

Federal, state and local government authorities in the U.S. and in other countries extensively regulate, among other things, the research, development, testing, manufacturing, quality control, approval, labeling, packaging, storage, record-keeping, promotion, advertising, distribution, post-approval monitoring and reporting, marketing and export and import of biological and pharmaceutical products such as those we are developing. Our vaccine candidates must be approved by the FDA before they may be legally marketed in the U.S. and by the appropriate foreign regulatory agency before they may be legally marketed in foreign countries. Generally, our activities in other countries will be subject to regulation that is similar in nature and scope as that imposed in the U.S., even though it may differ in certain respects. The process for obtaining regulatory marketing approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations require the expenditure of substantial time and financial resources. The rules and regulations that apply to our business are subject to change and it is difficult to foresee whether, how, or when such changes may affect our business.

U.S. Product Development Process

In the U.S., the FDA regulates pharmaceutical and biological products under the Federal Food, Drug and Cosmetic Act, Public Health Service Act, or PHSA, and implementing regulations. Products are also subject to other federal, state and local statutes and regulations. The process of obtaining regulatory approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations require the expenditure of substantial time and financial resources. Failure to comply with the applicable U.S. requirements at any time during the product development process, approval process or after approval, may subject an applicant to administrative or judicial sanctions. FDA sanctions could include, among other actions, refusal to approve pending applications, withdrawal of an approval, a clinical hold, warning letters, product recalls or withdrawals from the market, product seizures, total or partial suspension of production or distribution injunctions, fines, refusals of government contracts, restitution, disgorgement or civil or criminal penalties. Any agency or judicial enforcement action could have a material adverse effect on us. The process required by the FDA before a drug or biological product may be marketed in the U.S. generally involves the following:

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completion of nonclinical laboratory tests and animal studies according to GLPs, and applicable requirements for the humane use of laboratory animals or other applicable regulations;

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submission to the FDA of an IND which must become effective before human clinical trials may begin;

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performance of adequate and well-controlled human clinical trials according to the FDA’s regulations commonly referred to as good clinical practice (“GCP”), and any additional requirements for the protection of human research subjects and their health information, to establish the safety and efficacy of the proposed biological product for its intended use;

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submission to the FDA of a Biologics License Application (“BLA”) for marketing approval that meets applicable requirements to ensure the continued safety, purity, and potency of the product that is the subject of the BLA based on results of nonclinical testing and clinical trials;

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satisfactory completion of an FDA inspection of the manufacturing facility or facilities where the biological product is produced, to assess compliance with cGMP, to assure that the facilities, methods and controls are adequate to preserve the biological product’s identity, strength, quality and purity;

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potential FDA audit of the nonclinical study and clinical trial sites that generated the data in support of the BLA; and

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FDA review and approval, or licensure, of the BLA.

Before testing any biological vaccine candidate, including our tablet vaccine candidates, in humans, the vaccine candidate enters the preclinical testing stage. Preclinical tests, also referred to as nonclinical studies, include laboratory evaluations of product chemistry, toxicity and formulation, as well as toxicological and pharmacological studies in animal species, to assess the potential safety and activity of the vaccine candidate. The conduct of the preclinical tests must comply with federal regulations and requirements including GLPs for certain animal studies and the Animal Welfare Act, which is enforced by the Department of Agriculture. The clinical trial sponsor must submit the results of the preclinical tests, together with manufacturing information, analytical data, any available clinical data or literature and a proposed clinical protocol, to the FDA as part of the IND. Some preclinical testing may continue even after the IND is submitted. Any person or entity sponsoring clinical trials in the U.S. to evaluate a product candidate’s safety and effectiveness must submit to the FDA, prior to commencing such trials, an IND application, which provides a basis for the FDA to conclude that there is an adequate basis for testing the product in humans. The IND automatically becomes effective 30 days after receipt by the FDA, unless the FDA raises concerns or questions regarding the proposed clinical trials and places the trial on a clinical hold within that 30-day time period. In such a case, the IND sponsor and the FDA must resolve any outstanding concerns before the clinical trial can begin. The FDA may also impose clinical holds on a biological product candidate at any time before or during clinical trials due to safety concerns or non-compliance. If the FDA imposes a clinical hold, trials may not recommence without FDA authorization and then only under terms authorized by the FDA. Accordingly, we cannot be sure that submission of an IND will result in the FDA allowing clinical trials to begin, or that, once begun, issues will not arise that suspend or terminate such trials.

Clinical trials involve the administration of the biological product candidate to healthy volunteers or patients under the supervision of qualified investigators, generally physicians not employed by or under the trial sponsor’s control. Clinical trials are conducted under protocols detailing, among other things, the objectives of the clinical trial, dosing procedures, subject selection and exclusion criteria, and the parameters to be used to monitor subject safety, including stopping rules that assure a clinical trial will be stopped if certain adverse events should occur. Each protocol and any amendments to the protocol must be submitted to the FDA as part of the IND. Clinical trials are subject to extensive regulation. Clinical trials must be conducted and monitored in accordance with the FDA’s bioresearch monitoring regulations and regulations composing the GCP requirements, including the requirement that all research subjects provide informed consent. Further, each clinical trial must be reviewed and approved by an independent institutional review board, or IRB, at or servicing each institution at which the clinical trial will be conducted. An IRB is charged with protecting the welfare and rights of trial participants and considers such items as whether the risks to individuals participating in the clinical trials are minimized and are reasonable in relation to anticipated benefits. The IRB also approves the form and content of the informed consent that must be signed by each clinical trial subject or his or her legal representative and must monitor the clinical trial until completed.

Foreign studies conducted under an IND must meet the same requirements applicable to studies conducted in the U.S. However, if a foreign study is not conducted under an IND, the data may still be submitted to the FDA in support of a product application, if the study was conducted in accordance with GCP and the FDA is able to validate the data.

The sponsor of a clinical trial or the sponsor’s designated responsible party may be required to register certain information about the trial and disclose certain results on government or independent registry websites, such as clinicaltrials.gov.

Human clinical trials are typically conducted in three sequential phases that may overlap or be combined:

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Phase 1. The biological product is initially introduced into a small number of healthy human subjects and tested for safety and to develop detailed profiles of its pharmacological and pharmacokinetic actions, determine side effects associated with increasing doses, and if possible, gain early evidence of effectiveness. In the case of some products for severe or life-threatening diseases, especially when the product may be too inherently toxic to ethically administer to healthy volunteers, the initial human testing is often conducted in subjects.

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Phase 2. The biological product is evaluated in a limited patient population to identify possible adverse effects and safety risks, to preliminarily evaluate the efficacy of the product for specific targeted diseases and to determine dosage tolerance, optimal dosage and dosing schedule.

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Phase 3. Clinical trials are undertaken to further evaluate dosage, clinical efficacy, potency, and safety in an expanded patient population at geographically dispersed clinical trial sites. These clinical trials are intended to establish the overall risk to benefit profile of the product and provide an adequate basis for product labeling. Phase 3 data often form the core basis on which the FDA evaluates a product candidate’s safety and effectiveness when considering the product application.

Post-approval clinical trials, sometimes referred to as Phase 4 clinical trials, may be conducted after initial marketing approval. These clinical trials are used to gain additional experience from the treatment of patients in the intended therapeutic indication, particularly for long-term safety follow-up.

During all phases of clinical development, regulatory agencies require extensive monitoring and auditing of all clinical activities, clinical data, and clinical trial investigators. Annual progress reports detailing the results of the clinical trials must be submitted to the FDA. Written IND safety reports must be promptly submitted to the FDA and the investigators for serious and unexpected adverse events, any findings from other studies, tests in laboratory animals or in vitro testing that suggest a significant risk for human subjects, or any clinically important increase in the rate of a serious suspected adverse reaction over that listed in the protocol or investigator brochure. The sponsor must submit an IND safety report within 15 calendar days after the sponsor determines that the information qualifies for reporting. The sponsor also must notify the FDA of any unexpected fatal or life-threatening suspected adverse reaction within seven calendar days after the sponsor’s initial receipt of the information. Phase 1, Phase 2 and Phase 3 clinical trials may not be completed successfully within any specified period, if at all. The FDA or the sponsor or its data safety monitoring board may suspend or terminate a clinical trial at any time on various grounds, including a finding that the research subjects are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or terminate approval of a clinical trial at its institution if the clinical trial is not being conducted in accordance with the IRB’s requirements or if the biological product has been associated with unexpected serious harm to subjects.

Concurrently with clinical trials, companies usually complete additional studies and must also develop additional information about the physical characteristics of the biological product as well as finalize a process for manufacturing the product in commercial quantities in accordance with cGMP requirements. To help reduce the risk of the introduction of adventitious agents with use of biological products, the PHSA emphasizes the importance of manufacturing control for products whose attributes cannot be precisely defined. The manufacturing process must be capable of consistently producing quality batches of the product candidate and, among other criteria, the sponsor must develop methods for testing the identity, strength, quality, potency and purity of the final biological product. Additionally, appropriate packaging must be selected and tested, and stability studies must be conducted to demonstrate that the biological product candidate does not undergo unacceptable deterioration over its shelf life.

U.S. Review and Approval Processes

After the completion of clinical trials of a biological product, FDA approval of a BLA must be obtained before commercial marketing of the biological product. The BLA must include results of product development, laboratory and animal studies, human trials, information on the manufacture and composition of the product, proposed labeling and other relevant information. The FDA may grant deferrals for submission of data, or full or partial waivers. The testing and approval processes require substantial time and effort and there can be no assurance that the FDA will accept the BLA for filing and, even if filed, that any approval will be granted on a timely basis, if at all.

Under the Prescription Drug User Fee Act (“PDUFA”), as amended, each BLA must be accompanied by a significant user fee. The FDA adjusts the PDUFA user fees on an annual basis. PDUFA also imposes an annual program fee for biological products. Fee waivers or reductions are available in certain circumstances, including a waiver of the application fee for the first application filed by a small business.

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Within 60 days following submission of the application, the FDA reviews a BLA submitted to determine if it is substantially complete before the agency accepts it for filing. The FDA may refuse to file any BLA that it deems incomplete or not properly reviewable at the time of submission and may request additional information. In this event, the BLA must be resubmitted with the additional information. The resubmitted application also is subject to review before the FDA accepts it for filing. Once the submission is accepted for filing, the FDA begins an in-depth substantive review of the BLA. FDA performance goals generally provide for action on a BLA within 12 months of submission. That deadline can be extended under certain circumstances, including by the FDA’s requests for additional information. The FDA reviews the BLA to determine, among other things, whether the proposed product is safe, potent, and/or effective for its intended use, and has an acceptable purity profile, and whether the product is being manufactured in accordance with cGMP to assure and preserve the product’s identity, safety, strength, quality, potency and purity. The FDA may refer applications for novel biological products or biological products that present difficult questions of safety or efficacy to an advisory committee, typically a panel that includes clinicians and other experts, for review, evaluation and a recommendation as to whether the application should be approved and under what conditions. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions. During the biological product approval process, the FDA also will determine whether a Risk Evaluation and Mitigation Strategy, or REMS, is necessary to assure the safe use of the biological product. If the FDA concludes a REMS is needed, the sponsor of the BLA must submit a proposed REMS. The FDA will not approve a BLA without a REMS, if required.

Before approving a BLA, the FDA will inspect the facilities at which the product is manufactured. The FDA will not approve the product unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. Additionally, before approving a BLA, the FDA will typically inspect one or more clinical sites to assure that the clinical trials were conducted in compliance with IND trial requirements and GCP requirements. To assure cGMP and GCP compliance, an applicant must incur significant expenditure of time, money and effort in the areas of training, record keeping, production, and quality control.

Notwithstanding the submission of relevant data and information, the FDA may ultimately decide that the BLA does not satisfy its regulatory criteria for approval and deny approval. Data obtained from clinical trials are not always conclusive and the FDA may interpret data differently than we interpret the same data. If the agency decides not to approve the BLA in its present form, the FDA will issue a complete response letter that describes all of the specific deficiencies in the BLA identified by the FDA. The deficiencies identified may be minor, for example, requiring labeling changes, or major, for example, requiring additional clinical trials. Additionally, the complete response letter may include recommended actions that the applicant might take to place the application in a condition for approval. The complete response letter may also request additional information, including additional preclinical or clinical data, for the FDA to reconsider the application. If a complete response letter is issued, the applicant may either resubmit the BLA, addressing all of the deficiencies identified in the letter, or withdraw the application.

If a product receives regulatory approval, the approval may be significantly limited to specific diseases and dosages or the indications for use may otherwise be limited, which could restrict the commercial value of the product.

Further, the FDA may require that certain contraindications, warnings or precautions be included in the product labeling. The FDA may impose restrictions and conditions on product distribution, prescribing, or dispensing in the form of a risk management plan, or otherwise limit the scope of any approval. In addition, the FDA may require post marketing clinical trials, sometimes referred to as Phase 4 clinical trials, designed to further assess a biological product’s safety and effectiveness, and testing and surveillance programs to monitor the safety of approved products that have been commercialized.

In addition, under the Pediatric Research Equity Act, a BLA or supplement to a BLA must contain data to assess the safety and effectiveness of the product for the claimed indications in all relevant pediatric subpopulations and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The FDA may grant deferrals for submission of data or full or partial waivers.

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Obtaining approval can take years, requires substantial resources and depends on a number of factors, including the severity of the targeted disease or condition, the availability of alternative treatments, and the risks and benefits demonstrated in clinical trials.

Post-Approval Requirements

Any products for which we receive FDA approvals are subject to continuing regulation by the FDA, including, among other things, record-keeping requirements, reporting of adverse experiences with the product, providing the FDA with updated safety and efficacy information, product sampling and distribution requirements, and complying with FDA promotion and advertising requirements, which include, among others, standards for direct-to-consumer advertising, restrictions on promoting products for uses or in patient populations that are not described in the product’s approved uses, known as ‘off-label’ use, limitations on industry-sponsored scientific and educational activities, and requirements for promotional activities involving the internet. Although physicians may prescribe legally available products for off-label uses, if the physicians deem to be appropriate in their professional medical judgment, manufacturers may not market or promote such off-label uses. If ongoing regulatory requirements are not met, or if safety problems occur after a product reaches market, the FDA may take actions to change the conditions under which the product is marketed, including limiting, suspending or even withdrawing approval.

In addition, quality control and manufacturing procedures must continue to conform to applicable manufacturing requirements after approval to ensure the long-term stability of the product. cGMP regulations require among other things, quality control and quality assurance as well as the corresponding maintenance of records and documentation and the obligation to investigate and correct any deviations from cGMP. Manufacturers and other entities involved in the manufacture and distribution of approved products are required to register their establishments with the FDA and certain state agencies and are subject to periodic unannounced inspections by the FDA and certain state agencies for compliance with cGMP and other laws. Accordingly, manufacturers must continue to expend time, money, and effort in the area of production and quality control to maintain cGMP compliance. Discovery of problems with a product after approval may result in restrictions on a product, manufacturer, or holder of an approved BLA, including, among other things, recall or withdrawal of the product from the market. In addition, changes to the manufacturing process are strictly regulated, and depending on the significance of the change, may require prior FDA approval before being implemented. Other types of changes to the approved product, such as adding new indications and claims, are also subject to further FDA review and approval.

Discovery of previously unknown problems with a product or the failure to comply with applicable FDA requirements can have negative consequences, including adverse publicity, judicial or administrative enforcement, warning letters from the FDA, mandated corrective advertising or communications with doctors, and civil or criminal penalties, among others. Newly discovered or developed safety or effectiveness data may require changes to a product’s approved labeling, including the addition of new warnings and contraindications, and also may require the implementation of other risk management measures. Also, new government requirements, including those resulting from new legislation, may be established, or the FDA’s policies may change, which could delay or prevent regulatory approval of our tablet vaccine candidates under development.

Other U.S. Healthcare Laws and Compliance Requirements

In the U.S., our activities are potentially subject to regulation by various federal, state and local authorities in addition to the FDA, including but not limited to, the Centers for Medicare and Medicaid Services, or CMS, other divisions of the U.S. Department of Health and Human Services, for instance the Office of Inspector General, the U.S. Department of Justice, or DOJ, and individual U.S. Attorney offices within the DOJ, and state and local governments. For example, sales, marketing and scientific/educational grant programs must comply with the anti-fraud and abuse provisions of the Social Security Act, the false claims laws, the physician payment transparency laws, the privacy and security provisions of the Health Insurance Portability and Accountability Act, or HIPAA, as amended by the Health Information Technology and Clinical Health Act, or HITECH, and similar state laws, each as amended.

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The federal Anti-Kickback Statute prohibits, among other things, any person or entity, from knowingly and willfully offering, paying, soliciting or receiving any remuneration, directly or indirectly, overtly or covertly, in cash or in kind, to induce or in return for purchasing, leasing, ordering or arranging for the purchase, lease or order of any item or service reimbursable under Medicare, Medicaid or other federal healthcare programs. The term remuneration has been interpreted broadly to include anything of value. The Anti-Kickback Statute has been interpreted to apply to arrangements between pharmaceutical manufacturers on one hand and prescribers, purchasers, and formulary managers on the other. There are a number of statutory exceptions and regulatory safe harbors protecting some common activities from prosecution. The exceptions and safe harbors are drawn narrowly and practices that involve remuneration that may be alleged to be intended to induce prescribing, purchasing or recommending may be subject to scrutiny if they do not qualify for an exception or safe harbor. Our practices may not in all cases meet all of the criteria for protection under a statutory exception or regulatory safe harbor. Failure to meet all of the requirements of a particular applicable statutory exception or regulatory safe harbor, however, does not make the conduct per se illegal under the Anti-Kickback Statute. Instead, the legality of the arrangement will be evaluated on a case-by-case basis based on a cumulative review of all of its facts and circumstances.

Additionally, the intent standard under the Anti-Kickback Statute was amended by the Affordable Care Act to a stricter standard such that a person or entity no longer needs to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation. In addition, the Affordable Care Act codified case law that a claim including items or services resulting from a violation of the federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the federal False Claims Act (“FCA”), as discussed below.

The civil monetary penalties statute imposes penalties against any person or entity that, among other things, is determined to have presented or caused to be presented a claim to a federal health program that the person knows or should know is for an item or service that was not provided as claimed or is false or fraudulent.

The federal FCA prohibits, among other things, any person or entity from knowingly presenting, or causing to be presented, a false claim for payment to, or approval by, the federal government or knowingly making, using, or causing to be made or used a false record or statement material to a false or fraudulent claim to the federal government. As a result of a modification made by the Fraud Enforcement and Recovery Act of 2009, a claim includes “any request or demand” for money or property presented to the U.S. government. Recently, several pharmaceutical and other healthcare companies have been prosecuted under these laws for allegedly providing free product to customers with the expectation that the customers would bill federal programs for the product. Other companies have been prosecuted for causing false claims to be submitted because of the companies’ marketing of the product for unapproved, and thus non-reimbursable, uses.

HIPAA created new federal criminal statutes that prohibit knowingly and willfully executing, or attempting to execute, a scheme to defraud or to obtain, by means of false or fraudulent pretenses, representations or promises, any money or property owned by, or under the control or custody of, any healthcare benefit program, including private third-party payors and knowingly and willfully falsifying, concealing or covering up by trick, scheme or device, a material fact or making any materially false, fictitious or fraudulent statement in connection with the delivery of or payment for healthcare benefits, items or services. Similar to the federal Anti-Kickback Statute, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation.

Also, many states have similar fraud and abuse statutes or regulations that apply to items and services reimbursed under Medicaid and other state programs, or, in several states, apply regardless of the payor.

We may be subject to data privacy and security regulations by both the federal government and the states in which we conduct our business. HIPAA, as amended by the HITECH Act, imposes requirements relating to the privacy, security and transmission of individually identifiable health information. Among other things, HITECH makes HIPAA’s privacy and security standards directly applicable to business associates, independent contractors or agents of covered entities that receive or obtain protected health information in connection with providing a service on behalf of a covered entity. HITECH also created four new tiers of civil monetary penalties, amended HIPAA to make civil and criminal penalties directly applicable to business associates, and gave state attorneys general new authority to file civil actions for damages or injunctions in federal courts to enforce the federal HIPAA laws and seek attorneys’ fees and costs associated with pursuing federal civil actions. In addition, state laws govern the privacy and security of health information in specified circumstances, many of which differ from each other in significant ways, thus complicating compliance efforts.

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Additionally, the Federal Physician Payments Sunshine Act under the Affordable Care Act, and its implementing regulations, require that certain manufacturers of drugs, devices, biological and medical supplies for which payment is available under Medicare, Medicaid or the Children’s Health Insurance Program, with certain exceptions, to report information related to certain payments or other transfers of value made or distributed to physicians and teaching hospitals, or to entities or individuals at the request of, or designated on behalf of, the physicians and teaching hospitals and to report annually certain ownership and investment interests held by physicians and their immediate family members. Failure to submit timely, accurately, and completely the required information may result in civil monetary penalties of up to an aggregate of $150,000 per year and up to an aggregate of $1 million per year for “knowing failures”. Certain states also mandate implementation of compliance programs, impose restrictions on pharmaceutical manufacturer marketing practices and/or require the tracking and reporting of gifts, compensation and other remuneration to healthcare providers and entities.

In order to distribute products commercially, we must also comply with state laws that require the registration of manufacturers and wholesale distributors of drug and biological products in a state, including, in certain states, manufacturers and distributors who ship products into the state even if such manufacturers or distributors have no place of business within the state. Some states also impose requirements on manufacturers and distributors to establish the pedigree of product in the chain of distribution, including some states that require manufacturers and others to adopt new technology capable of tracking and tracing product as it moves through the distribution chain. Several states have enacted legislation requiring pharmaceutical and biotechnology companies to establish marketing compliance programs, file periodic reports with the state, make periodic public disclosures on sales, marketing, pricing, clinical trials and other activities, and/or register their sales representatives, as well as to prohibit pharmacies and other healthcare entities from providing certain physician prescribing data to pharmaceutical and biotechnology companies for use in sales and marketing, and to prohibit certain other sales and marketing practices. All of our activities are potentially subject to federal and state consumer protection and unfair competition laws.

If our operations are found to be in violation of any of the federal and state healthcare laws described above or any other governmental regulations that apply to us, we may be subject to penalties, including without limitation, civil, criminal and/or administrative penalties, damages, fines, disgorgement, exclusion from participation in government programs, such as Medicare and Medicaid, injunctions, private “qui tam” actions brought by individual whistleblowers in the name of the government, or refusal to allow us to enter into government contracts, contractual damages, reputational harm, administrative burdens, diminished profits and future earnings, and the curtailment or restructuring of our operations, any of which could adversely affect our ability to operate our business and our results of operations.

Coverage, Pricing and Reimbursement

Significant uncertainty exists as to the coverage and reimbursement status of any tablet vaccine candidates for which we obtain regulatory approval. In the U.S. and markets in other countries, sales of any products for which we receive regulatory approval for commercial sale will depend, in part, on the extent to which third-party payors provide coverage, and establish adequate reimbursement levels for such products. In the U.S., third-party payors include federal and state healthcare programs, private managed care providers, health insurers and other organizations. The process for determining whether a third-party payor will provide coverage for a product may be separate from the process for setting the price of a product or for establishing the reimbursement rate that such a payor will pay for the product. Third-party payors may limit coverage to specific products on an approved list, also known as a formulary, which might not include all of the FDA-approved products for a particular indication. Third-party payors are increasingly challenging the price, examining the medical necessity and reviewing the cost-effectiveness of medical products, therapies and services, in addition to questioning their safety and efficacy. We may need to conduct expensive pharmaco-economic studies in order to demonstrate the medical necessity and cost-effectiveness of our tablet vaccine candidates, in addition to the costs required to obtain the FDA approvals. Our tablet vaccine candidates may not be considered medically necessary or cost-effective. A payor’s decision to provide coverage for a product does not imply that an adequate reimbursement rate will be approved. Further, one payor’s determination to provide coverage for a product does not assure that other payors will also provide coverage for the product. Adequate third-party reimbursement may not be available to enable us to maintain price levels sufficient to realize an appropriate return on our investment in product development.

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Different pricing and reimbursement schemes exist in other countries. Some jurisdictions operate positive and negative list systems under which products may only be marketed once a reimbursement price has been agreed. To obtain reimbursement or pricing approval, some of these countries may require the completion of clinical trials that compare the cost-effectiveness of a particular product candidate to currently available therapies. Other countries allow companies to fix their own prices for medicines but monitor and control company profits. The downward pressure on health care costs has become very intense. As a result, increasingly high barriers are being erected to the entry of new products. In addition, in some countries, cross-border imports from low-priced markets exert a commercial pressure on pricing within a country.

The marketability of any tablet vaccine candidates for which it receives regulatory approval for commercial sale may suffer if the government and third-party payors fail to provide adequate coverage and reimbursement. In addition, emphasis on managed care in the U.S. has increased and we expect the pressure on healthcare pricing will continue to increase. Coverage policies and third-party reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more products for which we receive regulatory approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

U.S. Healthcare Reform

We anticipate that current and future U.S. legislative healthcare reforms may result in additional downward pressure on the price that we receive for any approved product, if covered, and could seriously harm our business. Any reduction in reimbursement from Medicare and other government programs may result in a similar reduction in payments from private payors. The implementation of cost containment measures or other healthcare reforms may prevent us from being able to generate revenue, attain profitability or commercialize our tablet vaccine candidates. In addition, it is possible that there will be further legislation or regulation that could harm our business, financial condition and results of operations.

Foreign Regulation

In order to market any product outside of the U.S., we would need to comply with numerous and varying regulatory requirements of other countries and jurisdictions regarding quality, safety and efficacy and governing, among other things, clinical trials, marketing authorization, commercial sales and distribution of our products. Whether or not we obtain FDA approval for a product, we would need to obtain the necessary approvals by the comparable foreign regulatory authorities before we can commence clinical trials or marketing of the product in foreign countries and jurisdictions. Although many of the issues discussed above with respect to the U.S. apply similarly in the context of the European Union, the approval process varies between countries and jurisdictions and can involve additional product testing and additional administrative review periods. The time required to obtain approval in other countries and jurisdictions might differ from and be longer than that required to obtain FDA approval. Regulatory approval in one country or jurisdiction does not ensure regulatory approval in another, but a failure or delay in obtaining regulatory approval in one country or jurisdiction may negatively impact the regulatory process in others.

Information Privacy and Security

We are subject to federal and state laws and regulations that regulate the use, security, and disclosure of certain types of personal data. These include the federal regulations promulgated under the authority of the Health Insurance Portability and Accountability Act of 1996 (“HIPAA”) that require us to provide certain protections to individuals regarding their health information. The HIPAA privacy and security regulations extensively regulate the use and disclosure of protected health information (“PHI”) and require covered entities, which include healthcare providers and health plans, and their business associates to implement and maintain administrative, physical, and technical safeguards to protect the security of such information. Additional security requirements apply to electronic PHI. These regulations also provide individuals with substantive rights with respect to their health information.

The HIPAA privacy and security regulations also require us to enter into written agreements with our covered entity customers and our subcontractors, also known as business associates, to whom we disclose PHI. Covered entities may be subject to penalties as a result of a business associate violating HIPAA, if the business associate is found to be an agent of the covered entity. Business associates are also directly subject to liability under certain HIPAA privacy and security regulations and may be found liable for the violations of their agents.

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HIPAA requires covered entities to notify affected individuals of breaches of unsecured PHI without unreasonable delay but no later than 60 days after discovery of the breach. If a business associate is acting as an agent of a covered entity, then the covered entity must provide the required notifications to individuals based on the time when the business associate discovered the breach. Reporting must also be made to the HHS Office for Civil Rights (“OCR”) and, for breaches of unsecured PHI involving more than 500 residents of a state or jurisdiction, to the media. Impermissible uses or disclosures of unsecured PHI are presumed to be breaches unless the covered entity or business associate establishes that there is a low probability the PHI has been compromised. Various state laws and regulations may also require us to notify affected individuals and the state regulators in the event of a data breach involving personal information without regard to the probability of the information being compromised. State laws and standard practice often provide for shorter data breach reporting timelines than required by HIPAA.

Violations of the HIPAA privacy and security regulations may result in criminal penalties and in substantial civil penalties per violation. The civil penalties are adjusted annually based on updates to the consumer price index. OCR is required to perform compliance audits and investigates HIPAA compliance in response to complaints and reports of breaches. In addition to enforcement by OCR, state attorneys general are authorized to bring civil actions seeking either injunction or damages in response to violations of HIPAA privacy and security regulations that threaten the privacy of state residents. OCR may resolve HIPAA violations through informal means, such as allowing a covered entity to implement a corrective action plan, but OCR has the discretion to move directly to impose monetary penalties and is required to impose penalties for violations resulting from willful neglect. There can be no assurance that we will not be the subject of an investigation (arising out of a reportable breach incident, audit or otherwise) alleging noncompliance with HIPAA regulations in our maintenance of PHI.

The Federal Trade Commission Act (“FTCA”) also empowers the Federal Trade Commission to implement rules and regulations protecting personal information, and to take enforcement action when data practices constitute unfair or deceptive acts or practices. The FTC regularly takes enforcement action and has emphasized the protection of medical and other health care information as an enforcement priority. Following the United Stated Supreme Court’s Dobbs decision and state laws that may criminalize certain health care procedures, types of personal information not traditionally thought of as health-related now may reveal personal information about health care decisions, heightening governmental scrutiny of data privacy practices.

In addition to HIPAA and the FTCA, numerous state and federal laws and regulations govern the collection, dissemination, use, privacy, confidentiality, security, availability, integrity, creation, receipt, transmission, storage, and other processing of medical. health care, employment, consumer, and other personal information. Privacy and data security statutes and regulations vary from state to state, and these laws and regulations in many cases are more restrictive than, and generally are not preempted by, the FTCA and HIPAA and their implementing rules. These laws and regulations regulate how personal information is used, sold, and shared; grant individuals substantive rights regarding their data that data processers are obligated to honor; impose rigorous information security and data breach obligations; and in some instances provide private rights of action to individuals affected by alleged violations of the laws in addition to the costs and liabilities arising from government enforcement.

We also may be subject to international data protection regulations related to the collection, transmission, storage and use of employee data. For example, the General Data Protection Regulation (“GDPR”), which became effective on May 25, 2018, imposes strict compliance obligations on the collection, use, retention, security, processing, transfer and deletion of personal information and creates enhanced rights for individuals, including requirements relating to processing health and other sensitive data, obtaining consent of the individuals to whom the information relates in certain circumstances, providing information to individuals regarding data processing activities, implementing safeguards to protect the security and confidentiality of personal data, providing notification of data breaches and taking certain measures when engaging third-party processors that will have access to personal data. The GDPR also imposes strict rules on the transfer of personal data to countries outside the European Economic Area, including the U.S. and the United Kingdom. Entities that fail to comply with the requirements of the GDPR may be subject to very significant penalties, including potential fines of up to the greater of €20 million or 4% of annual global revenue.

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Government regulators, privacy advocates and class action attorneys are also increasingly scrutinizing how companies collect, process, use, store, share and transmit other types of personal data. For example, the California Consumer Privacy Act of 2018 (“CCPA”), which went into effect on January 1, 2020, and was significantly modified by the California Privacy Rights Act (“CPRA”), which became fully effective on January 1, 2023, applies broadly to information that identifies or is associated with any California household or individual, and requires that we implement several operational changes, including processes to respond to individuals’ requests regarding their personal information. The CPRA also creates a new enforcement agency to enforce the CCPA and CPRA and imposes additional requirements, including privacy risk assessments, audits and vendor contractual requirements for data sharing, license and access arrangements. The CCPA and CPRA provide for civil penalties for violations and allow private rights of action for data breaches. Virginia, Colorado, Connecticut and Utah have also passed comprehensive privacy legislation that take effect during 2023, and several other states, as well as federal lawmakers, have proposed additional consumer privacy legislation. The complex, dynamic legal landscape regarding privacy, data protection and information security creates significant compliance challenges for us, potentially restricts our ability to collect, use and disclose data, and exposes us to additional expense, and, if we cannot comply with applicable laws in a timely manner or at all, adverse publicity, harm to our reputation, and liability.

Greenhouse Gas Emission Related Policies, Regulation, and Legislation

Governments across the globe have announced and implemented various policies, regulation, and legislation to support the transition from fossil fuels to low-carbon forms of energy and the infrastructure around that transition. The operation of our business and our customers’ use of our products and solutions and services as well as our digital applications are and may in the future be, impacted by these various government actions. In August 2022, the U.S. passed the Inflation Reduction Act (“IRA”), which consists of a number of provisions aimed directly at confronting the climate change crisis. The climate-related provisions of the IRA are projected to cut emissions by up to 40% from 2005 GHG levels in the U.S. by 2030. Among other things, the IRA introduces an ITC for standalone energy storage, which is anticipated to lower capital cost of equipment. The IRA also contains provisions with incentives for grid modernization equipment, including domestic battery cell manufacturing, battery module manufacturing and its components as well as various upstream applications. It is unknown what form any future changes or any law would take under the incoming Trump administration, and how or whether it may affect our business in the future.

Employees and Human Capital Resources

Our management and scientific teams possess considerable experience in vaccine and anti-infective research, clinical development and regulatory matters. Our research and development team includes Ph.D.-level scientists with expertise in mucosal immunology, T cells, viral vectors and virology. General and administrative includes finance, human resources, administration, business and general management. As of December 31, 2025, we had approximately 65 full-time equivalent employees, excluding interns. Our full-time equivalent employees comprised of approximately 50 in research and development and 15 in general and administrative capacities.

We also had 9 full-time equivalent contractors as of December 31, 2025.

We do not have collective bargaining agreements with our employees and have not experienced any work stoppages. We consider our relations with our employees to be good.

Our human capital resources objectives include identifying, recruiting, training, retaining, and incentivizing our existing and new employees. We maintain an equity incentive plan, the principal purpose of which is to attract, retain and reward personnel through the granting of stock-based compensation awards, in order to increase stockholder value and the success of our company by motivating such individuals to perform to the best of their abilities and achieve our objectives. We offer an employee stock purchase plan, the principal purpose of which is to assist employees in acquiring a share ownership interest in Vaxart and to help such employees provide for their future security and to encourage them to remain in the employment of Vaxart. To facilitate talent attraction and retention, we strive to make Vaxart a safe and rewarding workplace, with opportunities for our employees to grow and develop in their careers, supported by competitive compensation, benefits and health and wellness programs, and by programs that build connections between our employees.

Legal Proceedings

The information included in “Note 7. Commitments and Contingencies—(c) Litigation” to the Condensed Consolidated Financial Statements for the Quarter Ended March 31, 2026 and “Note 8. Commitments and Contingencies, section-(c) Litigation” to the Consolidated Financial Statement for the Year Ended December 31, 2025 are incorporated by reference herein.

We may also from time to time be involved in legal proceedings arising in connection with our business. Based on information currently available, we believe that the amount, or range, of reasonably possible losses in connection with any pending actions against us in excess of established reserves, in the aggregate, is not material to our condensed consolidated financial condition or cash flows. However, any current or future dispute resolution or legal proceeding, regardless of the merits of any such proceeding, could result in substantial costs and a diversion of management’s attention and resources that are needed to run our business successfully, and could have a material adverse impact on our business, financial condition and results of operations.

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MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

You should read the following discussion and analysis of our financial condition and results of operations in conjunction with the financial statements which appear beginning on page F-1 of this prospectus and the information included elsewhere in this prospectus. Some of the information contained in this discussion and analysis or set forth elsewhere in this prospectus, including information with respect to our plans and strategy for our business, includes forward-looking statements involving risks and uncertainties as described under the heading “Forward-Looking Statements” elsewhere in this prospectus. You should review “Risk Factors” in this prospectus for a discussion of important factors that could cause actual results to differ materially from the results described in or implied by the forward-looking statements and could otherwise affect our intended plans of operations.

See “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included in our Annual Report on Form 10-K filed on March 20, 2025, for discussion and analysis of results of operations for the year ended December 31, 2024.

Company Overview

We are a clinical-stage biotechnology company primarily focused on the development of oral recombinant vaccines based on our Vector-Adjuvant-Antigen Standardized Technology (“VAAST”) proprietary oral vaccine platform. We are developing prophylactic vaccine candidates that target a range of infectious diseases, including norovirus (a widespread cause of acute gastroenteritis), coronavirus including SARS-CoV-2 (the virus that causes coronavirus disease 2019 (“COVID-19”)), and influenza. In addition, we have generated preclinical data for our first therapeutic vaccine candidate targeting cervical cancer an

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