UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K


☒	ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the Fiscal Year Ended December 31, ~~2024~~2025


☐	TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number: 001-~~36435~~12957

Enzon Pharmaceuticals, Inc.

(Exact name of registrant as specified in its charter)

Delaware		22-2372868
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification No.)
20 Commerce Drive (Suite 135), Cranford, New Jersey		07016
(Address of principal executive offices)		(Zip Code)

Registrant’s telephone number, including area code: (732) 980-4500

Securities registered pursuant to Section 12(b) of the Act:

Title of Each Class Trading Symbol(s) Name of Each Exchange on Which Registered None N/A N/A

Securities registered pursuant to Section 12(g) of the Act:

Common Stock, $0.01 par value

Series A-1 Junior Participating Preferred Stock Purchase Rights

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. ☐ Yes ☒ No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act. ☐ Yes ☒ No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. ☒ Yes ☐ No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). ☒ Yes ☐ No

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 ☐

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 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive oﬃcers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). ☐ Yes ☒ No

The aggregate market value of the Common Stock, $0.01 par value per share (“the “Common Stock”), held by non-affiliates of the registrant was approximately $64,~~814~~921,~~434~~536 as of June 28 30, ~~2024~~2025, based upon the closing sale price quoted on the ~~OTCQX~~OTCQB market of the OTC Markets Group, Inc. of $0.1813 per share reported for such date. Shares of Common Stock held by each executive officer and director and certain beneficial owners of 10% or more of the Common Stock of the registrant as of June 30, ~~2024~~2025 have been excluded in that such shares may be deemed to be owned by affiliates. This determination of affiliate status is not necessarily a conclusive determination for other purposes.

There were 74,214,603 shares of Common Stock issued and outstanding as of February 1410, ~~2025~~2026.

DOCUMENTS INCORPORATED BY REFERENCE

If the registrant files a definitive proxy statement relating to its ~~2025~~2026 Annual Meeting of Stockholders with the U.S. Securities and Exchange Commission (the “Commission”) not later than 120 days after December 31, ~~2024~~2025, portions of such definitive proxy statement will be incorporated by reference into Part III of this Annual Report on Form 10-K where indicated. However, if such definitive proxy statement is not filed with the Commission in such 120-day period, the registrant will file an amendment to this Annual Report on Form 10-K with the Commission not later than the end of such 120-day period to include the information required by Part III of Form 10-K.

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ENZON PHARMACEUTICALS, INC.

~~2024~~2025 Annual Report on Form 10-K

Table of Contents

		Page
	PART I
Item 1.	Business	4
Item 1A.	Risk Factors	5
Item 1B.	Unresolved Staff Comments	109
Item 1C	Cybersecurity	10
Item 2.	Properties	10
Item 3.	Legal Proceedings	10
	PART II
Item 5.	Market for Registrant’s Common Equity, Related Stockholder Matters, and Issuer Purchases of Equity Securities	11
Item 6.	Reserved	1112
Item 7.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	1112
Item 7A.	Quantitative and Qualitative Disclosures About Market Risk	16
Item 8.	Financial Statements and Supplementary Data	16
Item 9.	Changes in and Disagreements With Accountants on Accounting and Financial Disclosure	16
Item 9A.	Controls and Procedures	1617
Item 9B.	Other Information	17
Item 9C.	Disclosure Regarding Foreign Jurisdictions that Prevent Inspection	17

	PART III
Item 10.	Directors, Executive Officers and Corporate Governance	18
Item 11.	Executive Compensation	18
Item 12.	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters	18
Item 13.	Certain Relationships and Related Transactions, and Director Independence	18
Item 14.	Principal Accounting Fees and Services	18
	PART IV
Item 15.	Exhibits, Financial Statement Schedules	19
Item 16.	Form 10-K Summary	2021

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Unless the context requires otherwise, references in this Annual Report on Form 10-K to “Enzon,” the “Company,” “we,” “us,” or “our” and similar terms mean Enzon Pharmaceuticals, Inc. and its subsidiaries.

This Annual Report on Form 10-K contains forward-looking statements within the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements contained in this Annual Report on Form 10-K, other than statements that are purely historical, are forward-looking statements. Forward-looking statements can be identified by the use of forward-looking terminology such as “believes,” “expects,” “may,” “will,” “should,” “could,” “potential,” “anticipates,” “estimates,” “plans,” “would,” or “intends” or the negative thereof, or other variations thereof, or comparable terminology, or by discussions of strategy. Forward-looking statements are based upon management’s present expectations, objectives, anticipations, plans, hopes, beliefs, intentions or strategies regarding the future and are subject to risks and uncertainties that could cause actual results, events or developments to be materially different from those indicated in such forward-looking statements, including the risks and uncertainties set forth in Item 1A. Risk Factors of this Annual Report on Form 10-K. These risks and uncertainties should be considered carefully and readers are cautioned not to place undue reliance on such forward-looking statements. We cannot assure that the future results covered by the forward-looking statements will be achieved. All information in this Annual Report on Form 10-K speaks only as of the date of the filing of this report, unless otherwise indicated. We do not intend to update this information to reflect events after the date of this report.

Our website is located at www.enzon.com. Copies of our Annual Reports on Form 10-K, our Quarterly Reports on Form 10-Q, our Current Reports on Form 8-K and our other reports filed with the Securities and Exchange Commission (the “SEC” or the “Commission”) can be obtained, free of charge, as soon as reasonably practicable after such material is electronically filed with, or furnished to the SEC, by calling (732) 980-4500, by clicking the SEC Filings link from the Investors and Media page on our website at www.enzon.com or directly from the SEC’s website at www.sec.gov. Our website and the information contained therein or connected thereto are not incorporated into this Annual Report on Form 10-K.

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UNITED STATES SECURITIES AND EXCHANGE COMMISSION

FORM 10-K

ENZON PHARMACEUTICALS, INC.

PART I.

Item 1. Business

OVERVIEW

Enzon Pharmaceuticals, Inc. (together with its subsidiaries, the “Company,” “Enzon,” “we” or “us”) is positioned as a public company acquisition vehicle~~, where we can become an acquisition platform and potentially utilize our net operating loss carryforwards (“NOLs”) in an effort to enhance stockholder value~~. We were incorporated on May 11, 1983.

~~In September 2020~~Historically, we ~~initiated~~have areceived ~~rights~~royalty ~~offering~~revenues ~~(the~~from ~~“Rights~~licensing ~~Offering”)~~arrangements ~~for~~with ~~our~~other ~~common~~companies ~~and~~primarily ~~preferred~~related ~~stock,~~to ~~which~~sales ~~closed~~of incertain ~~October~~drug ~~2020~~products ~~(see~~that ~~below~~utilized ~~and~~Enzon’s ~~Note~~proprietary 12technology. toFor ~~our~~more ~~Consolidated~~than ~~Financial~~ten ~~Statements)~~years, ~~and~~ we ~~realized~~have ~~$43.6~~had ~~million~~no inclinical ~~gross~~operations ~~proceeds~~and limited corporate operations. ~~This~~We ~~has~~previously ~~enabled~~were usa party to ~~embark~~a onmarketing ~~our~~agreement ~~plan~~relating to ~~potentially~~the ~~realize~~drug ~~the~~Vicineum, ~~value~~which, ofif ~~our~~approved, ~~approximately~~could ~~$101.4~~have ~~million~~potentially ~~NOLs~~generated bymilestone ~~acquiring~~and ~~businesses~~royalty orpayments ~~assets,~~to ~~although~~us ~~there~~in ~~can~~the befuture. noHowever, ~~assurance~~our ~~that~~licensee wefor ~~will~~this bedrug ~~able~~was canceled by the counterparty to ~~realize~~the ~~all~~marketing oragreement ~~any~~and ~~portion~~our ofpatent ~~such~~for ~~value.~~Vicineum Tohas ~~protect~~since ~~the~~expired. ~~NOLs~~Accordingly, inwe ~~August~~do ~~2020,~~not ~~our~~believe ~~Board~~any offuture ~~Directors~~revenue ~~(the~~will ~~“Board”)~~be ~~adopted~~earned afrom ~~Section~~this ~~382~~product ~~rights~~or ~~plan~~that ~~(see~~if ~~Note~~any 11such torevenue ~~our~~is ~~Consolidated~~earned ~~Financial~~it ~~Statements)~~will be material.

~~Historically,~~Merger we have received royalty revenues from licensing arrangements with other companies primarily related to sales of certain drug products that utilized Enzon’s proprietary technology. In recent years, we have had no clinical operations and limited corporate operations. We have a marketing agreement relating to the drug Vicineum, which, if approved, will potentially generate milestone and royalty payments to us in the future. Currently, our licensee for this drug has announced that it is seeking a partner for further development of Vicineum. Accordingly, we cannot assure you that we will earn material future royalties or milestones from Vicineum or any other licensed patent.Agreement

On June 20, 2025, the Company, EPSC Acquisition ~~Activities~~Corp., a Delaware corporation and a wholly owned subsidiary of ours (“Merger Sub”), and Viskase Companies, Inc. (“Viskase”) entered into an Agreement and Plan of Merger, which was amended on October 24, 2025 (as amended, the “Merger Agreement”). Upon the terms and subject to the satisfaction or waiver of the conditions described in the Merger Agreement, at the effective time of the merger, Merger Sub will be merged with and into Viskase, with Viskase as the surviving entity following the merger as a wholly owned subsidiary of Enzon (the “Merger”). Following consummation of the Merger, it is anticipated that Enzon’s pre-closing stockholders, including holders of Enzon’s Series C Non-Convertible Redeemable Preferred Stock (the “Series C Preferred Stock”), will hold 45% of the outstanding shares of Enzon’s Common Stock following the Merger, and Viskase’s pre-closing stockholders will hold 55% of the outstanding shares of Enzon’s Common Stock following the Merger. If the Merger is completed, Enzon Pharmaceuticals, Inc. will change its name to “Viskase Holdings, Inc.” and its common stock will continue to be quoted on the OTCQB tier of the OTC Markets Group, Inc., although pursuant to the rules of the OTCQB, Enzon is required to re-apply to the OTCQB following such change of control transaction.

~~Our~~Support Board and our management are actively involved in pursuing, sourcing, reviewing, and evaluating various potential acquisition transactions consistent with our strategy. Our management and our Board have originated a number of potential acquisition opportunities and engaged in discussions with certain potential acquisition targets and financial advisors on behalf of various individual entities, while continuing to evaluate such potential transactions, including those transactions that could result in a change of control of us. We will continue to update our stockholders as material developments arise.Agreement

AsIcahn ~~discussed~~Enterprises inHoldings ~~Note~~L.P., 15a toDelaware ~~the~~limited ~~Condensed~~partnership ~~Consolidated~~(“IEH”), ~~Financial~~and ~~Statements~~certain of its affiliates (collectively with IEH, the ~~Company~~“IEH ~~has~~Parties”) ~~been~~beneficially ~~contacted~~own ~~with~~approximately ~~respect~~48.6% toof ~~exploring~~the aoutstanding ~~potential~~shares ~~business~~of ~~combination~~our ~~transaction~~Common ~~with~~Stock, anas ~~affiliate~~well as approximately 98.2% of the ~~Company’s~~outstanding ~~significant~~shares ~~stockholder,~~of ~~Carl~~our Series C. ~~Icahn~~Preferred Stock. ~~The~~In ~~Company~~connection with the execution of the Merger Agreement, ~~through~~IEH aand ~~special~~certain ~~committee~~of its affiliates entered into the Support Agreement, which was subsequently amended (as amended, the “Support Agreement”). Pursuant to the terms of the ~~Board~~Support Agreement, isthe ~~currently~~IEH inParties ~~discussions~~agreed ~~regarding~~to, ~~such~~among aother ~~transaction~~things, ~~and~~(i) ~~will~~deliver ~~update~~or ~~its~~cause ~~stockholders~~the ~~when~~delivery of written consents with respect to all of the issued and ifoutstanding ~~appropriate~~shares orof asEnzon’s ~~required~~Common Stock held by the ~~federal~~IEH ~~securities~~Parties ~~laws.~~to ~~There~~approve ~~can~~the beMerger noand ~~assurances~~the ~~that~~amendment ~~any~~to ~~agreement~~Enzon’s ~~will~~certificate beof ~~reached~~incorporation, orand ~~that~~(ii) aexchange ~~transaction~~all ~~will~~of bethe ~~consummated~~shares of Series C Preferred Stock held by the IEH Parties for the Company’s Common Stock prior to the consummation of the Merger.

~~Royalty~~Consent ~~and Milestone Agreements and Revenues~~Solicitation

~~Prior~~As torequired ~~2017,~~by wethe ~~received~~Merger ~~royalty~~Agreement, ~~revenues~~on ~~from~~January ~~sales of PegIntron~~30, ~~which is marketed by Merck & Co.~~2026, ~~Inc.~~Enzon ~~(“Merck”).~~commenced ~~The related patents have expired in all jurisdictions and we have received no royalties in recent years and expect to receive none in the future. There is~~ a ~~dispute~~consent ~~with~~solicitation ~~Merck regarding royalties~~ (~~see~~the ~~Note~~“Consent ~~4 to our Consolidated Financial Statements~~Solicitation”). Wefor ~~have~~its astockholders ~~licensing~~to ~~agreement~~provide ~~regarding~~written SCconsents ~~Oncaspar~~relating ~~and certain other drugs.~~to:

~~During~~(i)an amendment to the ~~years~~Company’s ~~ended~~Amended ~~December~~and ~~31,~~Restated ~~2024~~Certificate of Incorporation (the “Enzon Charter,” and ~~2023~~such amendment, wethe ~~received~~“Enzon aCharter ~~license~~Amendment”) ~~maintenance~~to ~~fee~~effect the consolidation of ~~approximately~~the ~~$26,000~~issued and ~~$0,~~outstanding ~~respectively,~~shares ~~from~~of ~~Amgen,~~the ~~Inc.~~Enzon’s inCommon ~~payment~~Stock ofat a ~~worldwide,~~ratio ~~royalty-free~~of ~~non~~1-~~exclusive~~for-100 ~~right~~(the to“Reverse ~~license~~Stock ~~Vicineum.~~Split” ~~(See~~and, ~~Note~~such 1proposal, tothe ~~our~~“Reverse ~~Consolidated~~Stock ~~Financial~~Split ~~Statements.~~Proposal”); and

~~Patents~~(ii)the ~~and~~adoption ~~Intellectual~~of ~~Property~~the ~~Rights~~Merger Agreement (the “Merger Proposal”) as more fully described in the Prospectus/Consent Solicitation/Offer to Exchange filed by Enzon with the SEC on January 30, 2026.

We have a portfolio of issued U.S. patents, many of which have foreign counterparts. None of these has generated significant royalties in recent years, except for two milestone payments received in connection with Vicineum. The patent related to PegIntron

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~~(peginterferon~~On ~~alfa-2b)~~February ~~expired~~11, in2026, ~~all~~Enzon ~~jurisdictions~~received aswritten consents from holders of ~~December~~its ~~31,~~Common ~~2024~~Stock that were sufficient to approve the Reverse Stock Split Proposal and the Merger Proposal. WeAs doof ~~not~~the ~~expect~~record date for the written consents, there were 74,214,603 shares of Enzon’s Common Stock outstanding and entitled to ~~generate~~vote. ~~material~~The ~~royalties~~Reverse ~~from~~Stock ~~any~~Split Proposal was approved by stockholders holding 40,993,338 shares of ~~our~~Enzon’s ~~existing~~Common ~~patents~~Stock or 55.2% of the issued and outstanding shares of Enzon’s Common Stock, and the Merger Proposal was approved by stockholders holding 42,350,448 shares of Enzon’s Common Stock or 57.1% of the issued and outstanding shares of Enzon’s Common Stock. Accordingly, no further action is required by holders of Enzon’s Common Stock with respect to the transactions contemplated by the Merger Agreement.

Series C Exchange Offer

As required by the Merger Agreement, on January 30, 2026, Enzon commenced an exchange offer (the “Series C Exchange Offer”) pursuant to which Enzon offered each holder of the its Series C Preferred Stock to exchange each share of Enzon’s Series C Preferred Stock held by such stockholder for a number of shares of Enzon’s Common Stock equal to (i) the aggregate liquidation preference of each share of Enzon’s Series C Preferred Stock, divided by (ii) $7.83 after giving effect to the Reverse Stock Split described above (referred to as the “Series C Exchange Offer”). The Series C Exchange Offer will expire one minute after 11:59 p.m., Eastern Time, on March 9, 2026, unless extended or terminated in Enzon’s sole discretion or in accordance with applicable law. For more information about the Series C Exchange Offer, please see the Prospectus/Consent Solicitation/Offer to Exchange, which was filed by Enzon with the SEC on January 30, 2026, and previously mailed to Enzon’s stockholders.

Consummation of the Merger

On February 11, 2026, the Reverse Stock Split Proposal and the Merger Proposal were approved by the requisite vote of holders of Enzon’s Common Stock. The closing of the transactions contemplated by the Merger Agreement is subject to satisfaction or waiver of the remaining conditions to closing as set forth in the Merger Agreement. The conditions to the closing of the transactions subject to the Merger Agreement are described in more detail in the Prospectus/Consent Solicitation/Offer to Exchange filed by Enzon with the SEC on January 30, 2026.

Royalty and Milestone Agreements and Revenues

Prior to 2017, we received royalty revenues from sales of PegIntron, which is marketed by Merck & Co., Inc. (“Merck”). The related patents have expired in all jurisdictions and we have received no royalties in recent years. We do not expect to receive any revenue from this product in the future. There is a dispute with Merck regarding royalties (see Note 4 to our Consolidated Financial Statements). We also have a licensing agreement regarding SC Oncaspar and certain other drugs.

During the years ended December 31, 2025 and 2024, we received license maintenance fees of approximately $0 and $26,000, respectively, from Amgen, Inc. in payment for a worldwide, royalty-free non-exclusive right to license Vicineum. Such license was canceled by Amgen, Inc. in 2025. (See Note 1 to our Consolidated Financial Statements.)

Patents and Intellectual Property Rights

We have a portfolio of issued Canadian patents, many of which have non-U.S. counterparts. None of these patents has generated significant royalties in recent years, except for two milestone payments received in 2021 in connection with Vicineum prior to the license for Vicineum being canceled in 2025. Our patent related to PegIntron (peginterferon alfa-2b) expired in all jurisdictions as of December 31, 2024. We do not expect to generate material royalties from any of our existing patents in the future.

EMPLOYEES AND EXECUTIVE OFFICERS

We currently have no employees. Our executive officer provides services to us on a consulting basis.

Item 1A. Risk Factors

You should carefully consider the following risk factors, as well as other information in this Annual Report, including our financial statements and the related notes and “Management’s Discussion and Analysis of Financial Condition and Results of Operations”, as well as our other public filings. Our business, financial condition and results of operations may be impacted by one or more of the following factors, any of which could cause actual results to vary materially from historical and current results or anticipated future results. As noted above, we have entered into the Merger Agreement with Viskase and our stockholders have approved the Reverse Stock Split Proposal and the Merger Proposal. Subject to the remaining conditions to closing being satisfied or waived, we

Risks Relating to the Company and its Operations

Our search for a business, company or assets to acquire or in which to invest may be unsuccessful, or it could result in a change of control, and we may fail to utilize the proceeds of our Rights Offering and/or realize the value of our NOLs.

We are positioned as a public company acquisition vehicle, where we can become an acquisition platform and potentially utilize our NOLs and enhance stockholder value. Although we may acquire businesses, entities or revenue streams that could generate sufficient income so that we can utilize our approximately $101.4 million in federal NOLs, there can be no assurance we will be able to do so. In addition, we do not have any current plans, arrangements or understandings with respect to any acquisitions or investments, and we may pursue acquisitions that could result in a change of control of us. Although we have had significant discretion in the use of the net proceeds of our Rights Offering, it is possible that we may not utilize such proceeds and if a transaction is pursued that results in a change of control, as defined in the Certificate of Designation of the Series C Non-Convertible Preferred Stock, holders of the Series C Non-Convertible Redeemable Preferred Stock will be entitled to redemption rights, and if exercised would require the Company to redeem such preferred stock. Further, if such change of control occurs, it would likely substantially limit the utilization of our NOLs. We cannot assure you that we will be able to realize the value of all or any of our NOLs.

For example, as discussed in Note 15 to the Condensed Consolidated Financial Statements, we have been contacted with respect to exploring a potential business combination transaction with an affiliate of our significant stockholder, Carl C. Icahn. The Company, through a special committee of the Board, is currently in discussions regarding such a transaction. There can be no assurances that any agreement will be reached or that a transaction will be consummated, or that if such a transaction is consummated, it won’t result in a change of control, or that we will be able to realize the value of all or any of our NOLs.

Our sources of revenue are limited and, as a result of our cash reserves, we expect only limited revenue and profitability for the foreseeable future; while we increased our cash reserve by completing the Rights Offering and generate revenue from such cash reserve, unanticipated liabilities and expenses could adversely affect our ability to engage in a public company acquisition or investment, as currently intended, or to continue operations.

Prior to 2023, we incurred losses and, in 2023 and 2024, our primary source of revenue was from interest income. We received approximately $43.1 million of net proceeds in the fourth quarter of 2020 from the Rights Offering, which we are using to position us as a public company acquisition vehicle, unless and until we can consummate an acquisition or investment that generates income, and other than interest income, we do not anticipate generating any additional cash or revenues. As interest rates may fluctuate in the future, there can be no assurance that we will continue to receive interest income at our existing levels, or at levels that allow us to achieve a profit. Accordingly, there can be no assurance that we will continue to generate a profit based on our interest income. In addition, because the patents have expired in all jurisdictions, we will receive no further royalties on sales of PegIntron, although there may be a potential liability to Merck for product returns and rebates. Based on current estimates, we do not expect any future liability for those returns and rebates to be material. Moreover, our right to receive royalty revenues from other products is limited and we currently do not intend to acquire new sources of royalty revenues. For those remaining existing or potential sources of royalty revenue, our licensees may be unable to maintain regulatory approvals for currently licensed products or obtain regulatory approvals for new products. Safety issues could also result in the failure to maintain regulatory approvals or decrease revenues.

While we have substantially reduced our operating expenses, including ceasing our research and development activities, eliminating our workforce in favor of independent contractors and consultants, and discontinuing our significant lease commitments,

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weexpect ~~may incur unanticipated liabilities or expenses, including expenses~~ to ~~defend~~consummate ~~unasserted~~the ~~product~~Merger ~~liability~~with ~~claims~~Viskase. orFor ~~greater~~more ~~than~~information ~~expected~~relating ~~liabilities~~to ~~for~~Viskase’s ~~PegIntron and expenses incurred in our search for a target~~ business, tofinancial ~~acquire~~condition orand inresults ~~which~~of tooperations, ~~invest.~~including ~~Any~~the ~~such~~related ~~expenses~~risks orthereto, ~~liabilities~~please ~~could~~see ~~impact~~ the ~~availability~~Prospectus/Consent ofSolicitation/Offer ~~assets that we expect~~ to ~~use~~Exchange, towhich ~~fund~~was ~~future~~filed ~~operations~~by orEnzon ~~adversely~~with ~~affect~~the ~~our~~SEC ~~ability~~on toJanuary ~~pay~~30, ~~dividends~~2026, orand ~~make~~previously ~~distributions~~mailed to ~~shareholders~~Enzon’s ~~upon a liquidation of the Company~~stockholders.

WeRisks ~~have~~Related ~~outsourced all corporate functions, which makes us more dependent on third parties~~ to ~~perform~~the ~~these~~Merger ~~corporate~~and ~~functions.~~Merger Agreement

WeThe ~~have~~interests ~~outsourced all corporate functions, which makes us more dependent on third parties for the performance~~ of ~~these~~our ~~functions.~~significant Tostockholders ~~the~~may ~~extent~~conflict that we are unable to effectively reallocate employee responsibilities, retain key officers as consultants, maintain effective internal control over financial reporting and effective disclosure controls and procedures, establish and maintain agreements with ~~competent third-party contractors on terms that are acceptable to us, or effectively manage~~ the ~~work~~interests ~~performed~~of byother ~~any retained third-party contractors, our ability to manage the operations effectively could be compromised~~stockholders.

~~While~~Mr. weCarl ~~may~~C. Icahn, ~~potentially~~directly and indirectly, ~~acquire~~beneficially ~~businesses~~owns approximately 48.6% of the outstanding shares of our Common Stock, ~~entities~~as orwell ~~revenue~~as ~~streams~~approximately ~~that~~98.2% ~~could~~of ~~generate~~the ~~sufficient~~outstanding ~~income~~Series soC Preferred Stock. Mr. Icahn may have interests that weare ~~can~~different ~~utilize~~from, in addition to or not always consistent with our ~~NOLs~~interests or with the interests of our other common or preferred stockholders. To the extent that conflicts of interest may arise between us and Mr. Icahn and his affiliates, wethose conflicts may be ~~unable~~resolved in a manner adverse to dous soor ~~and~~our other stockholders. In addition, ~~accordingly~~Mr. Icahn and his affiliates will continue to hold a significant portion of Enzon’s Common Stock following the consummation of the Merger. Accordingly, wethe interests of these significant stockholders may benot ~~unable~~always tocoincide ~~realize~~with our ~~deferred~~interests ~~income~~or ~~tax~~the ~~assets~~interests of other stockholders, or otherwise be in the best interests of us or all stockholders.

~~The~~Our ~~ultimate~~stockholders ~~realization~~(other ofthan ~~our~~Carl ~~deferred income tax assets is dependent upon generating future taxable income~~Icahn, ~~executing~~IEH ~~tax planning strategies,~~ and ~~reversals~~their ofrespective ~~existing~~affiliates) ~~taxable~~will ~~temporary~~experience ~~differences.~~immediate Wedilution ~~have recorded a partial valuation allowance against our deferred income tax assets, which may fluctuate~~ as ~~conditions change. While we are positioned as~~ a ~~public~~consequence ~~company~~of ~~acquisition~~the ~~vehicle~~issuance and may acquire businesses, entities or revenue streams that could generate sufficient income so that we can utilize our NOLs, we cannot provide any assurance that we will be able to do so. If we fail to do so, approximately 97% of ~~our~~shares ~~current federal NOLs will expire by 2036 and more than 90%~~ of our ~~current~~Common ~~federal~~Stock ~~NOLs~~in ~~will~~connection ~~expire~~with by the ~~end of 2031~~Merger. AsHaving a ~~result~~minority ofshare ~~the~~position ~~expiration~~will ~~dates~~reduce ofthe ~~our~~influence ~~NOLs~~that ~~and~~the ~~our~~pre-closing ~~efforts~~stockholders to(other ~~date~~than toCarl ~~identify acquisition candidates~~Icahn, weIEH ~~may~~and ~~consider~~their ~~transactions~~respective ~~that~~affiliates) ~~could~~have ~~result~~on inthe amanagement ~~change~~ of ~~control~~the ofpost-merger uscombined incompany an(the ~~effort~~“Combined toCompany”) ~~enhance~~following ~~stockholder~~the ~~value~~Merger.

~~Our~~It ~~ability~~is toanticipated ~~utilize~~that, ~~our~~upon ~~NOLs~~completion toof ~~offset~~the ~~our~~Merger ~~future~~and ~~taxable~~assuming ~~income~~that ~~and/or~~the toEnzon ~~recover~~Series ~~previously~~C ~~paid~~Preferred ~~taxes~~Stock ~~would~~is beexchanged ~~limited~~for orEnzon’s ~~could~~Common beStock ~~non-existent~~in iffull, we(i) ~~were~~the toholders ~~undergo~~of anEnzon’s ~~“ownership~~Common ~~change”~~Stock ~~within~~immediately prior to the ~~meaning~~Closing are expected to own approximately 5% of ~~Section~~the ~~382~~Enzon’s Common Stock, (ii) the holders of the ~~Internal~~Series ~~Revenue~~C ~~Code.~~Preferred InStock ~~general,~~are anexpected ~~“ownership~~to ~~change”~~own ~~occurs~~approximately ~~whenever~~40% of the ~~percentage~~Enzon’s Common Stock and (iii) Viskase stockholders are expected to own 55% of the ~~stock~~Enzon’s ofCommon aStock, ~~corporation~~subject ~~owned~~to bycertain ~~“5-percent~~adjustments ~~shareholders”~~based ~~(within~~upon the ~~meaning~~number of ~~Section~~shares ~~382~~ of ~~the~~Series ~~Internal~~C ~~Revenue~~Preferred ~~Code)~~Stock ~~increases~~exchanged for Enzon’s Common Stock by ~~more~~non-affiliates ~~than~~of 50the ~~percentage~~IEH ~~points~~Parties. ~~over~~If the ~~lowest~~actual ~~percentage~~facts differ from any of the ~~stock~~foregoing ofassumptions ~~such~~(which ~~corporation~~they ~~owned~~may), bythe ~~such~~percentage ~~“5-percent~~ownership ~~shareholders”~~retained atby ~~any~~pre-closing ~~time~~Enzon ~~over~~stockholders in the ~~testing~~Combined ~~period~~Company will differ.

AnUpon ~~ownership~~completion ~~change under Section 382~~ of the ~~Internal~~Merger, ~~Revenue~~the ~~Code~~issuance ~~would~~of ~~establish~~Enzon’s anCommon ~~annual~~Stock ~~limitation~~in toconnection with the ~~amount~~Merger ofand ~~NOLs~~the weother ~~could~~transactions ~~utilize~~contemplated toby ~~offset~~the ~~our~~Merger ~~taxable~~Agreement, ~~income~~will result in ~~any~~significant ~~single~~dilution ~~year. The application~~ of ~~these~~the ~~limitations~~ownership ~~might~~and ~~prevent~~voting ~~full~~interests ~~utilization~~ of the ~~deferred~~pre-closing ~~tax~~Enzon ~~assets~~stockholders, ~~attributable~~as todescribed ~~our NOLs~~above. ~~Although~~As ~~we have adopted~~ a ~~Section 382~~result, ~~rights~~pre-closing ~~plan~~Enzon instockholders an(other ~~effort~~than tothe ~~protect~~IEH ~~stockholder~~Parties) ~~value~~will byexperience ~~attempting~~a tosignificant ~~protect~~reduction ~~against~~in atheir ~~possible~~relative ~~limitation~~influence onover ~~our~~Enzon ~~ability~~following tothe ~~use~~Merger, ~~our NOLs~~which, wefollowing ~~cannot~~the ~~assure~~Merger, ~~you that we~~ will ~~not~~encompass ~~undergo an ownership change within~~ the ~~meaning~~combined businesses of ~~Section 382.~~Enzon ~~(See Notes 9~~ and ~~11 to the Consolidated Financial Statements~~Viskase.)

~~Risks~~Carl ~~Relating~~C. toIcahn, ~~Our~~IEH ~~Common~~and ~~Stock~~their respective affiliates will exert significant influence on the Company after the Merger and non-IEH stockholders will have limited governance rights.

~~Our~~Upon completion of the Merger, the Company expects that IEH and its affiliates will hold a substantial majority of the voting power of the Combined Company. As of the date of this filing, the Company believes that IEH, through its control of its affiliates, beneficially owned approximately (i) 48.6% of the issued and outstanding shares of the Company’s Common Stock, (ii) 98.2% of the issued and outstanding shares of the Company’s Series C Preferred Stock and (iii) 93.97% of the issued and outstanding shares of Viskase’s common stock. ~~ranks~~Following ~~junior~~the toMerger, ~~our~~it is expected that Mr. Icahn and his related entities will beneficially own approximately 93.32% of the outstanding shares of the Combined Company, assuming all of the Series C Preferred Stock is exchanged for Enzon’s Common Stock. Mr. Icahn is the controlling stockholder and chairman of the board of the general partner of IEH. Because of their substantial ownership and voting power, Mr. Icahn, IEH and their respective affiliates may exert significant influence over the management and strategic direction of the Combined Company following the Merger, including, but not limited to, (i) the declaration of any future dividends, (ii) the ability to control the election, removal or replacement of any one or more members of the board of directors of the Combined Company, (iii) the voting on decisions related to fundamental corporate actions, consolidations or sales of all or substantially all of the Combined Company’s assets and (iv) the ability to control the approval of various transactions. This concentration of ownership may also discourage or prevent a third party from seeking to acquire control of the Combined Company, even if such a transaction might be beneficial to other stockholders. As a result, the interests of Mr. Icahn, IEH and their respective affiliates may not always align with the interests of Enzon or its other stockholders.

With respect to the payment of cash dividends and amount payable in the event our liquidation, dissolution or winding up, our common stock will rank junior to our Series C Non-Convertible Redeemable Preferred Stock (“Series C Preferred Stock”). This means that, unless full dividends have been (i) paid, (ii) redeemed in an amount in excess of the initial liquidation value of $1,000 per share of Series C Preferred Stock or (iii) set aside for payment on all outstanding Series C Preferred Stock for all dividends or increases in the liquidation value in excess of the initial liquidation amount of $1,000 of such Series C Preferred Stock, no cash dividends may be declared or paid on our common stock. Likewise, in the event of our voluntary or involuntary liquidation, dissolution or winding up, no distribution of our assets may be made to holders of our common stock until we have paid to the holders of our Series C Preferred Stock the liquidation preference related to such Series C Preferred Stock, plus in each case any accrued and unpaid dividends.

In addition, the holders of Series C Preferred Stock have the right to demand that we redeem their shares in the event that we undergo a change of control. Accordingly, if such demands were made, there could be limited or no cash available to declare or make any dividends to holders of our common stock.

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~~The~~Following ~~interests~~completion of ~~our~~the ~~significant~~Merger, ~~stockholders~~as a result of Viskase’s operations, we may ~~conflict~~not ~~with~~realize the ~~interests~~anticipated benefits of ~~other~~the ~~stockholders~~Merger.

~~Mr.~~Until ~~Carl C. Icahn, directly and indirectly, beneficially owns approximately 49% of~~ the ~~outstanding~~completion ~~shares~~ of ~~our common stock, as well as approximately 98% of~~ the ~~outstanding Series C Preferred Stock. Mr. Icahn may have interests that are different from~~Merger, inEnzon ~~addition to or not always consistent with our interests or with the interests of our other common or preferred stockholders. To the extent that conflicts of interest may arise between us~~ and ~~Mr.~~Viskase ~~Icahn~~will ~~and~~continue ~~his affiliates, those conflicts may be resolved in a manner adverse~~ to usoperate oras ~~our~~separate ~~other stockholders~~companies. InThe ~~addition,~~success ~~the existence~~ of ~~significant stockholders may have~~ the ~~effect~~Merger ofwill ~~making~~depend iton ~~difficult for, or may discourage or delay, a third party from seeking to acquire a majority of our outstanding common stock, which may adversely affect~~ the ~~market~~success ~~price~~ of ~~our~~Viskase’s ~~common stock. In addition, such stockholders may exert significant influence over our~~ operations. ~~Accordingly,~~and ~~the~~performance ~~interests~~following ~~of these significant stockholders may not always coincide with our interests or~~ the ~~interests~~completion of ~~other stockholders, or otherwise be in~~ the ~~best interests of us or all stockholders~~Merger.

~~The~~Viskase’s ~~price~~operating ofperformance ~~our~~and ~~common~~financial ~~stock~~condition has ~~historically~~recently ~~been~~deteriorated ~~volatile~~as a result of, among other things, underperformance of the Viskase business in the second half of 2025, personnel changes and ~~may~~Viskase ~~decline~~pausing ~~significantly~~capital ifinvestment weinto ~~are~~one ~~unable~~of toits ~~consummate~~product alines. There can be no assurance that Viskase’s business ~~acquisition~~will not further decline before or ~~investment~~after completion of the Merger. We cannot assure you that the anticipated benefits of the Merger will be achieved.

~~Historically,~~We the market price of our common stock has fluctuated over a wide range for a variety of reasons, including Company-specific factors and global and industry-wide conditions and events such as the COVID-19 pandemic and resulting recession, as well as the fact that only a few stockholders, in the aggregate, hold more than a majority of our common stock, and, therefore, there is a small public float with limited trading activity in our common stock. In the future, the value of our common stock may not be ~~impacted~~able ~~by our lack of royalty revenues, our ability~~ to ~~monetize~~utilize our ~~remaining~~net ~~assets,~~operating ~~including~~loss ~~our~~carryforwards (“NOLs”), ~~and~~certain ~~any~~credits ~~unexpected~~and ~~liabilities~~other ortax ~~expenses~~attributes ~~that~~following ~~impact our continued operations, our ability to pay dividends or make distributions to our stockholders and~~ the ~~success~~completion of ~~any~~the ~~future activities which we undertake, including our ability to consummate a business acquisition or investment~~Merger.

InEnzon’s ~~addition~~accountants have performed an analysis under Section 382 of the Internal Revenue Code (“the Code”), ~~financings~~the results of which conclude, based on certain assumptions, that ~~may~~utilization of Enzon’s NOLs and certain other credit carryforwards should not be ~~available~~subject to usan annual limitation under ~~current~~Section ~~market~~382 ~~conditions~~of ~~frequently~~the ~~involve~~Code ~~sales~~(“Section at382”). ~~prices~~It ~~below~~is ~~the~~therefore ~~prices~~intended atthat ~~which~~the ~~our~~Merger, ~~common~~pursuant ~~stock~~to ~~currently~~the ~~trades~~terms onof the ~~OTCQX~~Merger Agreement, as ~~well~~amended asby the ~~issuance~~Merger Agreement Amendment, should not limit Enzon’s NOL carryforwards and other tax attributes under Section 382. However, Section 382 rules and the application of ~~warrants~~such orrules ~~convertible~~to ~~equity~~the Merger are complex and there is no assurance that ~~require~~the ~~exercise~~Internal orRevenue ~~conversion~~Service ~~prices~~will not reach a different conclusion under Section 382. If such a conclusion is made and an ownership change is found to have occurred, the amount of the Combined Company’s taxable income that ~~are~~could ~~calculated~~be inoffset by Enzon’s pre-ownership change NOL carryforwards and other tax attributes would be severely limited. However, notwithstanding the ~~future~~foregoing, atdue to the existence of a ~~discount~~valuation toallowance for substantially all of the ~~then~~deferred ~~market~~tax ~~price~~assets for both Enzon and Viskase, the effect of ~~our~~having ~~common~~an ~~stock~~ownership change under Section 382 of the Code may not be significant.

~~Our~~In ~~common~~addition, ~~stock~~following isthe ~~quoted~~Merger, onthe Combined Company’s ability to utilize NOLs, certain credits, and other tax attributes to offset the ~~OTCQX~~Combined ~~market~~Company’s future taxable income and/or payment of taxes would be limited if the ~~OTC~~Combined ~~Markets~~Company ~~Group, Inc~~experiences an “ownership change” within the meaning of Section 382 of the Code., ~~which~~An ~~has~~ownership achange ~~very~~under ~~limited~~Section ~~trading~~382 ~~market~~would ~~and~~establish an annual limitation to the amount of Enzon’s NOL carryforwards, ~~therefore~~certain credits, ~~market~~and ~~liquidity~~other ~~for~~tax ~~our~~attributes ~~common~~that ~~stock~~the isCombined ~~low~~Company ~~and~~could ~~our~~utilize ~~stockholders’~~in ~~ability~~any single year. Assuming the Combined Company has taxable income, it would potentially have higher cash tax obligations than if it were able to ~~sell~~utilize ~~their~~Enzon’s ~~shares~~NOLs, which could adversely affect the Combined Company’s financial condition, results of ~~our~~operations ~~common~~and ~~stock~~cash ~~may~~flows, beif ~~limited~~that occurred.

~~Our~~Enzon ~~common~~had ~~stock~~previously isadopted ~~quoted~~a onSection ~~the~~382 ~~OTCQX~~Rights ~~market~~Agreement, ofdated ~~the~~as ~~OTC~~of ~~Markets~~August ~~Group~~14, ~~Inc.~~ ~~and~~2020, ~~the~~by ~~quotation~~and ofbetween ~~our~~Enzon ~~common~~and ~~stock~~Continental onStock ~~the~~Transfer ~~OTCQX~~& ~~market~~Trust ~~does~~Company, ~~not~~as ~~assure~~rights ~~that~~agent a(as ~~liquid~~amended, ~~trading~~the ~~market~~“Rights ~~exists~~Agreement”), orwhich ~~will~~is ~~develop.~~specifically ~~Stocks~~designed ~~traded~~to onreduce the ~~OTCQX~~risk ~~market~~of ~~generally~~an ~~have~~ownership ~~very~~change ~~limited~~that ~~trading~~would ~~volume~~limit ~~and~~Enzon’s ~~exhibit~~ability ato ~~wider~~use ~~spread~~its ~~between~~NOL ~~the~~carryforwards. ~~bid/ask~~The ~~quotations~~Merger ~~than~~Agreement, ~~stocks~~however, ~~traded~~requires onthat ~~national~~the ~~exchanges.~~Rights ~~Moreover,~~Agreement abe ~~significant~~terminated ~~number~~prior ofto ~~institutional~~the ~~investors~~Merger ~~have~~becoming ~~investment~~effective. ~~policies~~Enzon ~~that~~plans ~~prohibit~~to ~~them~~further ~~from~~amend ~~trading~~the infinal ~~stocks~~expiration ondate under the ~~OTCQX~~Rights ~~marketplace.~~Agreement Asso athat ~~result,~~the ~~investors~~Rights ~~may~~Agreement ~~find~~remains itin ~~difficult~~effect until immediately prior to ~~dispose~~the closing of, orthe toMerger. ~~obtain~~Following ~~accurate~~the ~~quotations~~completion of the ~~price~~Merger, ofthe Rights Agreement will have been terminated, ~~our~~and ~~common~~Enzon ~~stock.~~will ~~This~~have ~~significantly~~no ~~limits~~similar protections in place. Although the ~~liquidity~~Combined ofCompany ~~our~~is ~~common~~expected ~~stock~~to ~~and~~adopt ~~may~~a ~~adversely~~similar ~~affect~~Section ~~the~~382 ~~market~~Rights ~~price~~Agreement, ofthere ~~our~~can ~~common~~be ~~stock~~no assurances that it will do so.

WeThe doMerger ~~not~~is ~~currently,~~subject ~~and are not expected in the future~~ to, ~~meet~~a ~~the~~number ~~listing standards~~ of ~~any~~closing ~~national~~conditions ~~exchange. On June 10~~and, ~~2024,~~if wethese ~~were~~conditions ~~notified~~are bynot satisfied, the ~~OTCQX~~Merger ~~Markets~~Agreement ~~Group~~may ~~that~~be weterminated ~~had~~in ~~regained~~accordance ~~compliance~~ with ~~the~~its ~~OTCQX’s~~terms ~~standards~~and ~~for~~the ~~continued~~Merger ~~qualification~~may asnot abe ~~result~~completed. ofIn ~~our stock price trading at~~addition, ~~or in excess of, $0.10 for~~ the ~~period~~parties ofhave ~~time that was required to regain compliance. We presently anticipate that our common stock will continue to be quoted on~~ the ~~OTCQX~~right ~~market. As a result of not expecting~~ to ~~meet~~terminate the ~~listing~~Merger ~~standards~~Agreement ofunder ~~any~~other ~~national~~specified ~~exchange~~circumstances, ~~investors~~in ~~must~~which ~~bear~~case the ~~economic~~Merger ~~risk~~would ofnot ~~holding~~be ~~their shares of our common stock for an indefinite period of time~~completed. In the future, our common stock could become subject to “penny stock” rules which impose additional disclosure requirements on broker-dealers and could further negatively impact market liquidity for our common stock and our stockholders’ ability to sell their shares of our common stock.

The ~~declaration~~Merger is subject to a number of ~~common~~closing ~~stock~~conditions ~~dividends~~and, isif ~~within~~these conditions are not satisfied or waived (to the ~~discretion~~extent ofpermitted ~~our~~by ~~Board~~law), the Merger will not be completed. The closing of the Merger is subject to ~~any~~the ~~applicable~~satisfaction ~~limitations~~or ~~under~~waiver ~~Delaware~~of ~~corporate~~certain ~~law,~~conditions. asThe ~~well~~following asconditions have not yet been satisfied: (i) the ~~requirements~~completion of the exchange offer of the Series C Preferred Stock., ~~Our~~(ii) ~~ability~~the accuracy of the parties’ representations and warranties, subject to ~~pay~~certain ~~dividends~~“materiality” and “material adverse effect” qualifications; (iii) compliance by the parties in all material respects with their respective covenants; (iv) no law or order making the ~~future~~Merger ~~depends~~illegal ~~on,~~or ~~among~~otherwise ~~other~~prohibiting ~~things,~~consummation ~~our~~of ~~fulfillment~~the Merger; (v) the shares of Combined Company Common Stock to be issued in the ~~conditions~~Merger having been approved for listing (subject to official notice of issuance) on the ~~Series C~~OTC ~~Preferred~~Markets; (vi) the consummation of the Reverse Stock Split, ~~declining~~which ~~royalty~~has ~~revenues,~~been ~~our~~approved ~~ability~~by toEnzon’s ~~acquire~~stockholders; ~~other~~(vii) ~~revenue~~dissenters’ ~~sources~~rights ~~and~~not ~~our~~having ~~ability~~been toexercised ~~manage~~by ~~expenses,~~Viskase ~~including~~stockholders ~~costs~~representing ~~relating~~more tothan ~~our~~three ~~ongoing~~percent ~~operations.~~(3%) of the outstanding shares of Viskase’s common stock; and (viii) Enzon having

The declaration of dividends is within the discretion of our Board, subject to any applicable limitations under Delaware corporate law, and, therefore, our Board could decide in the future not to declare dividends. In addition, as described elsewhere, our common stock ranks junior to the Series C Preferred Stock, and we cannot declare or pay cash dividends on our common stock unless

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weat ~~satisfy~~least ~~the~~$40 ~~dividend~~million ~~requirements~~in ofcash ~~such~~at ~~Series C Preferred Stock~~closing. ~~Also,~~In ~~our ability to pay dividends in the future depends on~~addition, ~~among~~either ~~other~~Enzon ~~things, interest rates, our future revenues, including any revenues from existing and any future royalties and/~~or ~~milestone~~Viskase ~~payments,~~may ~~our~~terminate ~~ability~~the toMerger ~~acquire~~Agreement ~~other~~if ~~revenue~~the ~~sources~~Merger ~~and~~is ~~our~~not ~~ability~~consummated toprior ~~manage expenses, including costs relating~~ to ~~our~~11:59 ~~ongoing operations~~p. ~~We expect little or no future royalties from existing products for which we have the right to receive royalties~~m. ~~In addition~~, ~~while~~eastern ~~we may acquire or invest in businesses~~time, ~~entities~~on orMarch ~~revenue streams and we may be entitled to a share of milestone and royalty payments from the approval and sale of Vicineum~~31, ~~we cannot assure you that we will be able to do so or that we will have sufficient royalty or milestone revenues to be able to pay dividends in the future~~2026.

WeThe ~~have~~Merger ~~adopted~~Agreement alimits ~~Section 382~~Enzon’s ~~rights~~ability ~~plan,~~to ~~which~~pursue ~~may~~alternatives ~~discourage~~to athe ~~corporate takeover~~Merger.

OnThe ~~August 14,~~Merger ~~2020,~~Agreement ~~our~~contains ~~Board~~provisions ofthat ~~Directors~~make ~~adopted~~it ~~the~~more ~~Section 382~~difficult ~~rights~~for ~~plan~~Enzon ~~and~~to ~~declared~~enter ainto ~~dividend~~alternative ~~distribution~~transactions. ofThe ~~one~~Merger ~~right~~Agreement ~~for~~contains ~~each~~certain ~~outstanding~~provisions ~~share~~that ofrestrict ~~our~~Enzon’s ~~common~~ability ~~stock~~ to, ~~stockholders~~among ofother ~~record~~things, atsolicit, ~~the~~initiate ~~close~~or ofknowingly ~~business~~facilitate onor ~~August 24,~~encourage ~~2020.~~(including ~~Each~~by ~~share~~way of ~~our~~furnishing ~~common~~non-public ~~stock~~information) ~~issued~~the ~~thereafter~~submission ~~will~~of ~~also~~inquiries ~~include~~regarding, ~~one~~or ~~right.~~the ~~Each~~making ~~right~~of ~~entitles~~any ~~its~~proposal ~~holder,~~or ~~under~~offer ~~certain~~that ~~circumstances~~constitutes, toor ~~purchase~~would ~~from~~reasonably usbe ~~one~~expected ~~one-thousandth~~to oflead ato, ~~share~~an ofoffer ~~our~~regarding ~~Series A-1~~a ~~Junior~~potential ~~Participating~~alternative ~~Preferred~~transaction ~~Stock~~to atthe anMerger ~~exercise~~from ~~price~~a ofthird $1party.20 ~~per right, subject to adjustment.~~

~~The~~We ~~Board~~have ~~adopted~~incurred ~~the~~direct ~~Section 382~~and ~~rights~~indirect ~~plan~~costs inas ~~an effort to protect stockholder value by attempting to protect against~~ a ~~possible~~result ~~limitation~~of onthe ~~our~~Merger ~~ability~~and towe ~~use our NOLs. We~~ may ~~utilize~~incur ~~these~~additional ~~NOLs~~direct ~~in certain circumstances to offset future United States taxable income~~ and ~~reduce~~indirect ~~our~~costs ~~United~~whether ~~States~~or ~~federal~~not ~~income tax liability. Because~~ the ~~Section 382~~Merger ~~rights~~is plan could make it more expensive for a person to acquire a controlling interest in us, it could have the effect of delaying or preventing a change in control even if a change in control was in our stockholders’ interestconsummated.

~~Anti~~We have incurred significant non-~~takeover~~recurring ~~provisions~~costs in connection with the Merger and we expect to incur additional costs following the completion of the Merger in order to integrate our ~~charter~~business ~~documents~~with Viskase’s business. These costs include legal, financial advisory, accounting, consulting and ~~under~~other ~~Delaware~~professional ~~corporate~~fees, ~~law~~as ~~may~~well ~~make~~as itregulatory ~~more~~filing ~~difficult~~fees and other transaction-related expenses. We have incurred these costs and expect that we will continue to ~~acquire~~incur usadditional costs whether or not the Merger is consummated. If we terminate the Merger Agreement or the Merger is not completed by the outside date provided in the Merger Agreement, ~~even~~we ~~though~~will ~~such~~have ~~acquisitions~~incurred ~~may~~substantial costs from the Merger that we will not be ~~beneficial~~able to recover. We anticipate that we will incur further costs before the Merger is consummated and that we will continue to incur costs to combine operations following the completion of the Merger, and such expenses could have an adverse impact on our ~~stockholders~~business, financial results and operations.

InIf ~~addition~~the toMerger ~~our~~is ~~Section 382~~not ~~rights plan~~completed, ~~provisions~~the ofbusiness, ~~our~~financial ~~certificate~~results ~~of incorporation~~ and ~~bylaws,~~stock asprices ~~well as provisions~~ of ~~Delaware~~Enzon ~~corporate law,~~ could ~~make it more difficult for a third party to acquire us, even though such acquisitions may~~ be ~~beneficial~~adversely ~~to our stockholders~~affected. ~~These anti-takeover provisions include:~~

●The ~~lack~~Merger ofis subject to a ~~provision~~number of conditions, and there can be no assurance that it will be completed. If the Merger is not consummated for ~~cumulative~~any ~~voting~~reason, inour ongoing business may be adversely affected. In addition, we may be subject to litigation related to any failure to complete the ~~election~~Merger or any failure to fulfill the parties’ respective obligations under the Merger Agreement and there is no guarantee that the market price of ~~directors;~~our Common Stock will not decline if the Merger is not completed. If the Merger is not completed, we cannot assure our stockholders that these risks will not materialize or will not materially adversely affect their businesses, financial results or stock prices.

●Our ~~the~~sources ~~ability~~ of ~~our~~revenue ~~Board~~are tolimited ~~authorize~~and ~~the~~we ~~issuance~~expect ofonly ~~“blank~~limited ~~check”~~revenue ~~preferred~~and ~~stock~~profitability tofor ~~increase~~ the ~~number~~foreseeable offuture ~~outstanding~~if ~~shares~~the ~~and~~Merger ~~thwart~~is anot ~~takeover~~completed. ~~attempt;~~

●On ~~advance~~June ~~notice~~23, ~~requirements~~2025, ~~for~~we ~~nominations~~entered ~~for~~into ~~election~~the toMerger Agreement. If the ~~Board~~Merger is consummated, our operations post-Closing will be comprised primarily of ~~Directors~~the operations of Viskase. However, if the Merger is not consummated, we currently have limited sources of revenue. Prior to 2024, we incurred losses and, in 2025 and 2024, our primary source of income was from interest income. Other than interest income, we do not anticipate generating any additional cash or ~~for~~revenues. ~~proposing~~As ~~matters~~interest ~~that~~rates may fluctuate in the future, there can be ~~acted~~no ~~upon~~assurance bythat ~~stockholders~~we will continue to receive interest income at ~~stockholder~~our ~~meetings;~~existing levels, or at levels that allow us to achieve a profit. We do not expect to receive any additional royalty revenues and even if we do receive any additional royalties, we do not expect that such amounts will be material. We currently do not intend to acquire new sources of royalty revenues. If we do not consummate the Merger, we will have only limited revenue relating to the interest income on our existing cash.

●Risks ~~limitations~~Relating onto ~~who~~Our ~~may~~Common ~~call a special meeting of stockholders.~~Stock

The ~~provisions~~price ~~described~~of ~~above,~~ our ~~Section 382~~Common ~~rights~~Stock ~~plan~~has ~~and~~historically ~~provisions~~been ofvolatile ~~Delaware~~and ~~corporate law relating to business combinations with interested stockholders, along with the significant amount of common stock beneficially owned by Mr. Icahn,~~ may ~~discourage,~~decline ~~delay or prevent a third party from acquiring us~~significantly. These provisions may also discourage, delay or prevent a third party from acquiring a large portion of our securities, or initiating a tender offer, even if our stockholders might receive a premium for their shares in the acquisition over the then current market price.

~~Risks~~Historically, ~~Related~~the market price of our Common Stock has fluctuated over a wide range for a variety of reasons, including Company-specific factors and global and industry-wide conditions and events such as the COVID-19 pandemic and resulting recession, as well as the fact that only a few stockholders, in the aggregate, hold more than a majority of our Common Stock, and, therefore, there is a small public float with limited trading activity in our Common Stock. For example, in the future, if we are unable to consummate the ~~Series C~~Merger, ~~Preferred~~the value of our Common Stock may be impacted by our lack of royalty revenues, our ability to monetize our remaining assets, including our NOLs, and any unexpected liabilities or expenses that impact our continued operations, our ability to pay dividends or make distributions to our stockholders and the success of any future activities which we undertake.

In the event of any dissolution, liquidation, or winding up of our Company, we may not be able to make distributions or payments in full to all the holders of the Series C Preferred Stock or, if required, we may not be able to redeem such shares.

The Series C Preferred Stock ranks senior to our common stock, but we may in the future issue one or more series of preferred stock that ranks senior to, junior to or pari passu with our Series C Preferred Stock. In the event of any dissolution, liquidation, winding up or change of control of our Company, we may not be able to make distributions or payments in full to all the holders of the Series C Preferred Stock or, if requested by such holders upon a change of control, to redeem the Series C Preferred Stock, in which case holders of the Series C Preferred Stock could lose some or all of the entire value of their investment.

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~~The~~Our ~~dividends~~Common Stock is quoted on ~~our~~the ~~Series~~OTCQB Cmarket ~~Preferred~~of ~~Stock~~the ~~can~~OTC beMarkets ~~paid~~Group, ~~either~~Inc., inwhich ~~cash~~has ora bevery ~~paid~~limited intrading ~~kind~~market byand, ~~increasing~~therefore, ~~the~~market ~~liquidation~~liquidity ~~value~~for ofour ~~the~~Common Stock is low and our stockholders’ ability to sell their shares of ~~Series~~our CCommon ~~Preferred~~ Stock may be limited.

~~The~~Our ~~terms~~Common ofStock is quoted on the ~~Series~~OTCQB Cmarket ~~Preferred~~of ~~Stock~~the ~~allow~~OTC ~~dividends~~Markets onGroup, Inc. and the ~~shares~~quotation of ~~Series~~our CCommon ~~Preferred~~ Stock toon bethe ~~paid~~OTCQB ~~either~~market indoes ~~cash~~not orassure bethat ~~paid~~a inliquid ~~kind~~trading bymarket ~~increasing~~exists ~~the~~or ~~liquidation~~will ~~value~~develop. ofStocks traded on the ~~shares~~OTCQB ofmarket ~~Series~~generally Chave ~~Preferred~~very ~~Stock~~limited trading volume and, ~~therefore,~~exhibit ~~allow~~a wider spread between the ~~repayment~~bid/ask quotations than stocks traded on national exchanges. Moreover, a significant number of ~~the~~institutional ~~principal~~investors ~~and~~have ~~accrued~~investment ~~dividends~~policies that prohibit them from trading in stocks on the ~~Series~~OTCQB Cmarketplace. ~~Preferred~~As ~~Stock~~a result, investors may find it difficult to bedispose ~~deferred~~of, ~~until~~or ~~the~~to ~~earliest~~obtain accurate quotations of the ~~redemption~~price of, our Common Stock. This significantly limits the ~~Series~~liquidity Cof ~~Preferred~~our Common Stock orand ~~upon~~may ~~our~~adversely ~~dissolution,~~affect ~~liquidation~~the ormarket ~~winding~~price upof our Common Stock. WeIn ~~may~~addition, ~~not~~although ~~have~~the ~~enough~~Common ~~capital~~Stock will continue to ~~repay~~trade on the ~~full~~OTCQB ~~amount~~market ofimmediately following the ~~principal~~Merger, ~~and~~there ~~accrued~~is ~~dividends~~no ~~when~~guarantee ~~the~~that ~~payment~~it ofwill ~~principal~~continue ~~and~~to ~~accrued~~do ~~dividends~~so onas a result of the ~~Series~~re-application Cprocess ~~Preferred~~that ~~Stock~~the ~~becomes~~Company ~~due~~is required to undertake following the Merger.

~~The~~Risks ~~Series C~~Relating ~~Preferred Stock is equity and is subordinate~~ to ~~our existing and future indebtedness and other liabilities, and your interests may be diluted in~~ the ~~event~~Series weC ~~issue~~Preferred ~~additional shares of preferred stock.~~Stock

Shares of the Series C Preferred Stock represent equity interests and do not constitute indebtedness. As such, the Series C Preferred Stock will rank junior to all of our indebtedness and other non-equity claims of our creditors with respect to assets available to satisfy our claims, including in our liquidation, dissolution or winding up. Our future debt, if any, may include restrictions on our ability to pay distributions to preferred stockholders. Unlike indebtedness, where principal and interest would customarily be payable on specified due dates, in the case of preferred stock such as the Series C Preferred Stock, dividends are payable only if declared by our Board of Directors (or a duly authorized committee thereof). Our ability to pay dividends on the Series C Preferred Stock may be limited by the terms of our agreements governing any future indebtedness and by the provisions of any other future agreements.

Subject to limitations prescribed by Delaware law and our charter, our Board of Directors is authorized to issue, from our authorized but unissued shares of capital stock, preferred stock in such classes or series as our Board of Directors may determine and to establish from time to time the number of shares of preferred stock to be included in any such class or series. The issuance of additional shares of Series C Preferred Stock or additional shares of preferred stock designated as ranking on parity with the Series C Preferred Stock would dilute the interests of the holders of shares of the Series C Preferred Stock, and the issuance of shares of any class or series of our capital stock expressly designated as ranking senior to the Series C Preferred Stock or the incurrence of additional indebtedness could affect our ability to pay distributions on, redeem or pay the liquidation preference on the Series C Preferred Stock.

The Series C Preferred Stock is not convertible into common stock.

The Series C Preferred Stock is not convertible into shares of common stock and, therefore, holders of Series C Preferred Stock have no rights with respect to shares of our common stock. In addition, the Series C Preferred Stock accrues dividends at a fixed rate. Accordingly, an increase in market price of our common stock will not necessarily result in an increase in the value of the Series C Preferred Stock. The value of the Series C Preferred Stock may depend more on dividend and interest rates for other preferred stock, commercial paper and other investment alternatives and our actual and perceived ability to pay dividends on, and in the event of dissolution satisfy the liquidation preference with respect to, the Series C Preferred Stock.

Holders of shares of Series C Preferred Stock have no voting rights.

Except as otherwise provided by law, or as set forth in the Certificate of Designation with respect to the Series C Preferred Stock, the holders of Series C Preferred Stock have no special voting rights and their consent will not be required for taking any corporate action. As a result, all matters submitted to stockholders, that do not otherwise require the separate vote of the holders of the Series C Preferred Stock, will be decided by the vote of holders of our ~~common~~Common ~~stock~~Stock. ~~Holders~~Accordingly, holders of our Series C Preferred Stock have no ability to influence corporate matters and, as a result, we may take actions that holders of our Series C Preferred Stock do not view as preferable.

There is no public market for the Series C Preferred Stock.

There is no established public trading market for the Series C Preferred Stock, and we do not expect a market to develop. We do not currently intend to apply for listing of the Series C Preferred Stock on any securities exchange or recognized trading system. Purchasers of the Series C Preferred Stock may be unable to resell their shares of Series C Preferred Stock or sell them only at an unfavorable price for an extended period of time, if at all.

Except for those holders of Series C Preferred Stock that elect to participate in the Series C Exchange Offer, the Series C Preferred Stock is not convertible into shares of Common Stock.

The Series C Preferred Stock is not convertible into shares of Common Stock and, therefore, holders of Series C Preferred Stock have no rights with respect to shares of our Common Stock. However, pursuant to the terms of the Merger Agreement, we agreed to commence the Series C Exchange Offer in order to allow the holders of our Series C Preferred Stock to elect to exchange their shares of Series C Preferred Stock into shares of our Common Stock. Holders of Series C Preferred Stock that do not participate in the Series C Exchange Offer will not have the right to exchange their shares of Series C Preferred Stock into shares of Enzon’s Common Stock following the expiration of the Series C Exchange Offer on March 9, 2026. In addition, the Merger Agreement prohibits us from paying dividends on the Series C Preferred Stock in cash. Any shares of our Series C Preferred Stock that are not exchanged for shares of our Common Stock in the Series C Exchange Offer will remain outstanding pursuant to their current terms. Under the terms of our Series C Preferred Stock, following the completion of the Merger, we may redeem any outstanding shares of our Series C Preferred Stock for a cash amount equal to the aggregate liquidation preference of such shares.

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Item 1B. Unresolved Staff Comments

Not applicable.

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Item 1C. Cybersecurity

As we have positioned ourselves as a public company acquisition vehicle, and have limited operations, we do not have any significant operations that face cybersecurity threats. Although we do depend on the digital technologies of third parties, and any deliberate attacks on, or security breaches in, systems or infrastructure that we utilize, including those of third parties, could lead to corruption or misappropriation of our assets, information and sensitive or confidential data, we do not consider that we face significant cybersecurity risk and have not adopted any cybersecurity risk management program or formal processes for assessing cybersecurity risk. Our board of directors is generally responsible for the oversight of risks from cybersecurity threats, if there is any, as such threats may pertain to the protection of our assets, and our Finance and Audit Committee is responsible for the oversight of risks from cybersecurity threats, as such threats may pertain to financial risks and exposures. In fiscal year ~~2024~~2025, we did not identify any cybersecurity threats that have materially affected or are reasonably likely to materially affect our business strategy, results of operations, or financial condition.

Item 2. Properties

We maintain our principal executive offices at 20 Commerce Drive, Suite 135, Cranford, New Jersey, 07016 through a services agreement with Regus Management Group, LLC.

Item 3. Legal Proceedings

From time to time, we ~~are~~may be engaged in litigation arising in the ordinary course of our business. We are not presently a party to any litigation ~~that we believe to be material~~ and we are not aware of any pending or threatened litigation against us ~~that we believe could have a material adverse effect on our business, operating result, financial condition or cash flows~~.

Item 4. Mine Safety Disclosures

Not applicable.

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PART II.

Market Information

On August 11, 2025, the Company was notified by the OTCQX Markets Group (the “OTCQX”), the marketplace for the over-the-counter trading of its stock, that it no longer met the standards for continued qualification for the OTCQX, in that its stock bid price had fallen below $0.10 per share for 30 consecutive calendar days. Since August 9 12, ~~2016~~2025, our common stock has been quoted for trading on the ~~OTCQX~~OTCQB market of the OTC Markets Group, Inc. under the trading symbol “ENZN.”

Over-the-counter market quotations reflect inter-dealer prices, without retail mark-up, markdown or commission and may not represent actual transactions.

If the Merger is completed, the Company’s Common Stock will continue to be quoted on the OTCQB tier of the OTC Markets Group, Inc., although pursuant to the rules of the OTCQB, Enzon is required to re-apply to the OTCQB following such change of control transaction.

Holders

As of February 1410, ~~2025~~2026, there were ~~725~~698 holders of record of our ~~common~~Common ~~stock~~Stock, which does not reflect persons or entities that hold the ~~common~~Common ~~stock~~Stock in nominee or “street” name through various brokerage firms and financial institutions.

Dividends

The declaration of dividends is within the discretion of our Board, subject to any applicable limitations under Delaware corporate law, and therefore our Board could decide in the future not to declare dividends. WePursuant ~~did~~to the terms of the Merger Agreement, we are not permitted to pay any ~~cash~~ dividends to ~~our~~the ~~common~~holders ~~stockholders~~of inour ~~2024~~Common Stock and ~~can~~we ~~provide~~are nonot ~~assurance~~permitted ~~that~~to ~~our~~pay ~~Board will declare~~ any cash dividends ~~payable~~ to the holders of our ~~common~~Series ~~stockholders~~C inPreferred Stock while the ~~future~~transactions contemplated by the Merger Agreement are pending. In addition, as our ~~common~~Common ~~stock~~Stock ranks junior to the Series C Preferred Stock, unless full dividends have been (i) paid, (ii) redeemed in an amount in excess of the initial liquidation value of $1,000 per share of Series C Preferred Stock or (iii) set aside for payment on all such outstanding Series C Preferred Stock for all dividends or increases in the liquidation value in excess of the initial liquidation amount of $1,000 of such Series C Preferred Stock, no cash dividends may be declared or paid on our ~~common~~Common ~~stock~~Stock. OnPreviously, on an annual basis, our Board may, at its sole discretion, cause a dividend with respect to the Series C Preferred Stock to be paid in cash to the holders in an amount equal to 3% of the liquidation preference as in effect at such time. Since June 20, 2025, following the execution of, and pursuant to, the Merger Agreement, we have been prohibited from paying such dividends in cash. If the dividend is not so paid in cash, the liquidation preference will be adjusted and increased annually by an amount equal to 5% of the liquidation preference per share as in effect at such time, that is not paid in cash to the holders on such date. Also, our ability to pay dividends in the future depends on, among other things, our cash on hand, interest rates, future revenues from existing royalties and/or milestone payments, our ability to acquire other revenue sources and our ability to manage expenses, including costs relating to our ongoing operations.

On December 20, 2024, our Board declared a cash dividend of 3% of the liquidation preference at December 31, 2023 ($42,483,286) of the Series C Preferred Stock, aggregating approximately $1,275,000 ($31.86 per share). Such dividend was paid on January 9, 2025 to the holders of record of our Series C Preferred Stock as of January 2, 2025.

Due to the restrictions in the Merger Agreement, Enzon was not permitted to pay a cash dividend on its Series C Preferred Stock for 2025. However, pursuant to the terms of the Series C Preferred Stock, if a cash dividend is not paid, we must accrete an increase in liquidation preference equal to 5% of the liquidation preference as in effect at such time. Accordingly, the Series C Preferred Stock was adjusted and increased by an amount equal to 5% of the liquidation preference as in effect at such time ($42,483,400), which aggregated approximately $2,124,000 ($53.10 per share) at December 31, 2025. Following such adjustment the liquidation preference of the Series C Preferred Stock at December 31, 2025 was approximately $44,607,400.

Unregistered Sales of Equity Securities

Not applicable

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Repurchase of Equity Securities

Not applicable.

Item 6. Reserved

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

The following discussion of our financial condition and results of operations should be read together with our consolidated financial statements and notes to those statements included elsewhere in this Annual Report on Form 10-K.

Forward-Looking Information and Factors That May Affect Future Results

The following discussion contains forward-looking statements within the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements contained in the following discussion, other than statements that are purely historical, are forward-looking statements. Forward-looking statements can be identified by the use of forward-looking terminology such as “believes,” “expects,” “may,” “will,” “should,” “could,” “potential,” “anticipates,” “estimates,” “plans,” “would,” or “intends” or the negative thereof, or other variations thereof, or comparable terminology, or by discussions of strategy. Forward-looking statements are based upon management’s present expectations, objectives, anticipations, plans, hopes, beliefs, intentions or strategies regarding the future and are subject to risks and uncertainties that could cause actual results, events or developments to be materially different from those indicated in such forward-looking statements, including the risks and uncertainties set forth in Item 1A. Risk Factors. These risks and uncertainties should be considered carefully and readers are cautioned not to place undue reliance on such forward-looking statements. As such, we cannot assure you that the future results covered by the forward-looking statements will be achieved.

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indicated in such forward-looking statements, including the risks and uncertainties set forth in Item 1A. Risk Factors. These risks and uncertainties should be considered carefully and readers are cautioned not to place undue reliance on such forward-looking statements. As such, we cannot assure you that the future results covered by the forward-looking statements will be achieved.

The percentage changes throughout the following discussion are based on amounts stated in thousands of dollars.

Overview

~~During~~Enzon ~~2020~~Pharmaceuticals, ~~the~~Inc. ~~Company~~(together ~~adopted~~with aits ~~Section 382 rights plan and completed a Rights Offering~~subsidiaries, ~~each as further described below. As a result of~~ the ~~successful~~“Company,” ~~completion of the Rights Offering~~“Enzon,” “we” ~~are~~or “us”) is positioned as a public company acquisition vehicle~~, where we can become an acquisition platform and potentially utilize our NOLs and enhance stockholder value~~. We may acquire businesses, entities or revenue streams that could generate sufficient income so that we can utilize our approximately $101.4 million of federal NOLs. To date, we have not identified any actionable acquisition candidates and, while we expect that, ultimately, we will be successful in realizing the value of our NOLs, we cannot assure you that we will be able to do so.

~~Prior to 2017~~Historically, ~~the~~we ~~primary~~had ~~source~~received ~~of our~~ royalty revenues ~~was derived~~ from ~~sales~~licensing ofarrangements ~~PegIntron,~~with ~~which~~other iscompanies ~~marketed~~primarily byrelated ~~Merck.~~to Wesales ~~currently~~of ~~have~~certain nodrug ~~clinical~~products ~~operations~~that ~~and~~utilized ~~limited~~Enzon’s ~~corporate~~proprietary ~~operations~~technology. WeFor ~~have~~more nothan ~~intention~~ten ofyears, ~~resuming~~we ~~any~~have ~~clinical development activities. We~~ had no ~~revenues~~clinical ~~from~~operations ~~sales~~and oflimited ~~PegIntron~~corporate ~~for~~operations. ~~the~~We ~~years~~previously ~~ended~~were ~~December~~a ~~31,~~party ~~2024~~to ~~and 2023. We have~~ a marketing agreement ~~with~~relating ~~Micromet~~to ~~AG, now part of Amgen, Inc. (~~the ~~“Micromet~~drug ~~Agreement”)~~Vicineum, ~~pursuant to~~ which, weif ~~may~~approved, becould ~~entitled~~have topotentially ~~certain~~generated milestone and royalty payments ifto ~~Vicineum,~~us ain ~~drug~~the ~~that~~future. ~~was being developed by Sesen~~However, ~~Inc.,~~our ~~(“Sesen”)~~licensee ~~is approved~~ for ~~the~~this ~~treatment~~drug ofwas ~~non-muscle~~canceled ~~invasive~~by ~~bladder~~the ~~cancer.~~counterparty ~~Sesen~~to ~~announced~~the ~~that~~marketing itagreement ~~had~~and ~~completed~~our apatent ~~merger~~for ~~with~~Vicineum ~~Carisma~~has ~~Therapeutics~~since ~~Inc~~expired. ~~(“Carisma”)~~Accordingly, ~~and~~we ~~that~~do ~~the~~not ~~combined~~believe ~~company~~any ~~will~~future ~~focus~~revenue onwill ~~the~~be ~~advancement~~earned offrom ~~Carisma’s~~this ~~proprietary~~product ~~cell~~or ~~therapy~~that ~~for~~if ~~the~~any ~~treatment~~such ofrevenue ~~cancer~~is ~~and~~earned ~~other disorders and that that~~ it ~~intends~~will tobe ~~seek a partner for the further development of Vicineum~~material.

~~Due~~Merger to the challenges associated with developing and obtaining approval for drug products, and the lack of our involvement in the development and approval process, there is substantial uncertainty as to whether we will receive any milestone or royalty payments under the Micromet Agreement~~. We will not recognize revenue until all revenue recognition requirements are met.~~

WeOn ~~may~~June be20, ~~entitled~~2025, the Company, EPSC Acquisition Corp., a Delaware corporation and a wholly owned subsidiary of ours (“Merger Sub”), and Viskase Companies, Inc. (“Viskase”) entered into an Agreement and Plan of Merger, which was amended on October 24, 2025 (as amended, the “Merger Agreement”). Upon the terms and subject to ~~certain~~the ~~potential~~satisfaction ~~future~~or ~~milestone~~waiver ~~payments~~of ~~contingent~~the ~~upon~~conditions described in the ~~achievement~~Merger Agreement, at the effective time of ~~certain~~the ~~regulatory~~merger, ~~approval-related~~Merger ~~milestones~~Sub bywill ~~third-party~~be ~~licensees~~merged with and into Viskase, with Viskase as the surviving entity following the merger as a wholly owned subsidiary of Enzon (the “Merger”). WeFollowing ~~cannot~~consummation ~~assure~~of ~~you~~the Merger, it is anticipated that weEnzon’s ~~will~~pre-closing ~~receive~~stockholders, ~~any~~including ~~milestone~~holders ~~payments~~of ~~resulting~~Enzon’s ~~from~~Series ~~our~~C ~~agreements~~Preferred ~~with~~Stock ~~any~~who exchange such stock for shares of ~~our~~Enzon’s ~~third~~Common Stock pursuant to the Series C Exchange Offer (see below), will hold 45% of the outstanding shares of Enzon’s Common Stock, and Viskase’s pre-~~party~~closing ~~licensees~~stockholders orwill ~~that~~hold ~~any~~55% ~~sales~~of the outstanding shares of ~~related~~Enzon’s ~~products~~Common Stock. If the Merger is completed, Enzon Pharmaceuticals, Inc. will bechange ~~made~~its name to “Viskase Holdings, Inc.” Weand its common stock will ~~not~~be ~~recognize~~quoted ~~revenue~~on ~~from~~the ~~any~~OTCQB tier of ~~our~~the ~~third~~OTC Markets Group, Inc., although pursuant to the rules of the OTCQB, Enzon is required to re-~~party~~apply ~~licensees~~to ~~until~~the ~~all~~OTCQB ~~revenue~~following ~~recognition~~such ~~requirements~~change ~~are~~of ~~met.~~control transaction

The Merger Agreement and the transactions contemplated thereby, including the anticipated amendment to the Company’s Amended and Restated Certificate of Incorporation to effect the consolidation of the issued and outstanding shares of the Enzon’s Common Stock at a ratio of 1-for-100 (which we refer to as the “Reverse Stock Split”), were approved by the requisite holders of Enzon’s Common Stock. The closing of the transactions contemplated by the Merger Agreement is subject to satisfaction or waiver of the remaining conditions to closing as set forth in the Merger Agreement. The conditions to the closing of the transactions subject to the Merger Agreement are described in more detail in the Prospectus/Consent Solicitation/Offer to Exchange filed by Enzon with the SEC on January 30, 2026.

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Series C Exchange Offer

As required by the Merger Agreement, on January 30, 2026, Enzon commenced an exchange offer pursuant to which Enzon offered each holder of the its Series C Preferred Stock to exchange each share of Enzon’s Series C Preferred Stock held by such stockholder for a number of shares of Enzon’s Common Stock equal to (i) the aggregate liquidation preference of each share of Enzon’s Series C Preferred Stock, divided by (ii) $7.83 after giving effect to the Reverse Stock Split (referred to as the “Series C Exchange Offer”). The Series C Exchange Offer will expire one minute after 11:59 p.m., Eastern Time, on March 9, 2026, unless extended or terminated in Enzon’s sole discretion or in accordance with applicable law.

The percentage changes throughout the following discussion are based on amounts stated in thousands of dollars and not the rounded millions of dollars reflected in this section.

Results of Operations (in thousands of dollars):


	For the
	Year Ended December 31,
	~~2024~~2025		~~2023~~2024
Revenues:
Royalties and milestones, net	$	26—	$	—26
Total revenues		26—		—26
Operating expenses:
General and administrative		1,~~353~~356		1,~~044~~353
Operating loss		(1,327)		(1,044)
Transaction expenses		3,955		—
Interest and dividend income		2,452		2,261
Operating loss		(5,311)		(1,327)
Income tax (expense) benefit		(347)		156
Interest and dividend income		1,921		2,452
Net income	$	778	$	1,373
Income tax expense		(19)		(347)
Net (loss) income	$	(3,409)	$	778

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Overview

The following table summarizes our royalties earned in ~~2024~~2025 and ~~2023~~2024:

Royalties and Milestones Revenues ~~(in thousands of dollars):~~


	~~For the Year Ended December 31,~~					%
	2025		%	2024		Change
	2024		Change		2023
Royalties and milestones revenues (in thousands of dollars)	$	—		$	26	(100)
Royalties and milestones revenues	26		100		—

The revenues in ~~2024~~2025 and ~~2023~~2024 were approximately $~~26,000~~0 and $026,000, respectively, from license fees from Amgen, Inc. (“Amgen”) in payment offor a worldwide, royalty-free non-exclusive right to license Vicineum. Our right to receive royalties on U.S. and European sales of PegIntron ~~have~~ expired in all jurisdictions as of December 31, 2024 and our agreement with Amgen in connection with Vicineum was canceled by Amgen.

At December 31, ~~2024~~2025 and ~~2023~~2024, we recorded a liability to Merck of approximately $331,000 based primarily on Merck’s assertions regarding recoupments related to prior returns and rebates, as discussed in Note 4 to the Consolidated Financial Statements.

We will receive no additional royalties from Merck.

Interest and Dividend Income ~~(in thousands of dollars):~~


	~~For the Year Ended December 31,~~					%
	2025		%2024			Change
	2024		Change		2023
Interest and dividend income (in thousands of dollars)	$	1,921	$	2,452		(22)
Interest and dividend income	$	2,452	8		$	2,261

Interest and dividend income is attributable to the interest and dividends received on the invested cash and cash equivalents we received from the $4643.96 million of proceeds from our rights offering (See Note 1311 to the ~~Condensed~~ Consolidated Financial Statements). Interest and dividend income increased by approximately $191,000, or 8%, to $2,452,000 for 2024 from $2,261,000 for 2023. The increase in interest and dividends income is primarily attributable to the higher rates of interest in 2024 as compared with 2023.

~~General and Administrative Expenses (in thousands of dollars):~~13

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and dividend income decreased by approximately $531,000, or 22%, to $1,921,000 for 2025 from $2,452,000 for 2024. The decrease in interest and dividends income is primarily attributable to the lower rates of interest and smaller balances in 2025 as compared with 2024.

Operating Expenses


	~~For the Year Ended December 31,~~					%
	2025		%2024			Change
	2024		Change		2023
General and administrative expenses (in thousands of dollars):	$	1,356	$	1,353		—
General and administrative expenses	$	1,353	30		$	1,044

For the year ended December 31, ~~2024~~2025, general and administrative expenses were approximately $1,~~353~~356,000, an increase of approximately $~~309~~3,000, ~~30%,~~substantially unchanged from $1,~~044~~353,000 in the prior year~~, primarily attributable to an increase in professional fees~~.

In ~~2024~~2025 and ~~2023~~2024, general and administrative expenses consisted primarily of consulting fees for executive services and outside professional services for accounting, audit, tax and legal services.

Transaction Expenses:

Transaction expenses incurred in connection with the Merger were approximately $3,955,000 for the year ended December 31, 2025. These expenses were, primarily, for legal, consulting and professional fees. There were no comparable amounts during the corresponding period in 2024. (See Note 13 to our Consolidated Financial Statements).

Income Taxes

AsFor ~~a result of our income, primarily from interest, exceeding our expenses for~~ the year ended December 31, ~~2024~~2025, we ~~realized~~incurred approximately $13,~~125~~390,000 in pre-tax book ~~income~~loss ~~before~~primarily ~~utilization~~due ofto ~~NOLs.~~increased Weexpenses ~~utilized~~related ~~approximately~~to ~~$1.1~~the ~~million~~pending ofMerger ~~our~~with ~~NOLs~~Viskase. We are projecting ~~2025~~2026 pre-tax book ~~income~~loss ~~due~~through tothe ~~interest~~expected ~~rates~~closing ondate ~~our~~of ~~short-term cash investments and~~ the ~~absence~~pending ofMerger ~~any~~with ~~acquisitions at this time~~Viskase. Upon review of positive and negative evidence ~~in determining a partial reversal of the valuation allowance~~, the Company has concluded that a ~~partial~~full ~~reversal of the~~ valuation allowance is necessary. Interest rates may fluctuate throughout 2025, however, they are not expected in the near term to return to the low rates of the past creating a projected taxable income position. Therefore, the Company will partially reverse the valuation allowances as of December 31, ~~2024~~2025. A deferred tax expense of $~~342~~17,000 was recorded during the year ended December 31, ~~2024~~2025. We may acquire businesses, entities or revenue streams that will generate sufficient income so that we can utilize our approximately $101.4 million NOLs. While we anticipate that, ultimately, we could be successful in realizing the value of our NOLs, we cannot assure you that we will be able to do so.

13Our management will continue to assess the need for this valuation allowance and will make adjustments when appropriate.

~~Table~~These projections and beliefs are based upon a variety of ~~Contents~~estimates and numerous assumptions made by our management with respect to, among other things, interest rates, expenses and transaction costs. As a result, we cannot assure you that the estimates and assumptions upon which these projections and beliefs are based will prove accurate, that the projected results will be realized or that the actual results will not be substantially higher or lower than projected.

Our management will continue to assess the need for this valuation allowance and will make adjustments when appropriate. Additionally, our management believes that our NOLs will not be limited by any changes in the Company’s ownership as a result of the successful completion of the Rights Offering. (See Note 13 to the Consolidated Financial Statements.)

These projections and beliefs are based upon a variety of estimates and numerous assumptions made by our management with respect to, among other things, interest rates, forecasted sales of the drug products for which we have the right to receive royalties, our ability to acquire businesses, entities or revenue streams that could generate sufficient income so that we can utilize our NOLs and other matters, many of which are difficult to predict, are subject to significant uncertainties and are beyond our control. As a result, we cannot assure you that the estimates and assumptions upon which these projections and beliefs are based will prove accurate, that the projected results will be realized or that the actual results will not be substantially higher or lower than projected.

Section 382 Rights Plan

On August 14, 2020, inwe anentered ~~effort~~into tothe ~~protect stockholder value by attempting to protect against a possible limitation on our ability to use our NOLs, our Board of Directors adopted a~~ Section 382 ~~rights~~Rights ~~plan~~Agreement ~~and~~with ~~declared~~Continental aStock ~~dividend~~Transfer ~~distribution~~& ofTrust ~~one right for each outstanding share of the~~ Company~~’s common stock to stockholders of record at the close of business on August 24~~, ~~2020.~~as ~~Accordingly, holders of the Company’s common stock own one preferred stock purchase right for each share of common stock owned by such holder. The~~ rights ~~are~~agent ~~not immediately exercisable and will become exercisable only upon the occurrence of certain events~~ (as ~~set~~amended, ~~forth in~~ the ~~Section~~“Rights ~~382 rights plan. If the rights become exercisable~~Agreement”), ~~each~~in ~~right~~order ~~would initially represent the right~~ to ~~purchase~~protect ~~from us one one-thousandth of a share of~~ our ~~Series~~net ~~A-1~~operating ~~Junior~~loss ~~Participating~~carryforwards ~~Preferred Stock~~(“NOLs”), ~~par~~certain ~~value~~credits ~~$0.01~~and ~~per~~other ~~share,~~tax ~~for a purchase price of $1~~attributes.20 ~~per~~The ~~right.~~Merger IfAgreement ~~issued,~~requires ~~each~~that ~~fractional~~we ~~share~~terminate ofthe ~~Series~~Rights ~~A-1~~Plan ~~Junior~~prior ~~Participating~~to ~~Preferred Stock would give~~ the ~~stockholder~~consummation ~~approximately the same dividend, voting and liquidation rights as does one share~~ of the ~~Company’s~~Merger. ~~common~~On ~~stock.~~February ~~However~~27, ~~prior to exercise~~2026, ~~a right does not give its holder any rights as a stockholder of~~ the Company, ~~including~~entered ~~any~~into ~~dividend,~~an ~~voting~~amendment orto ~~liquidation~~the ~~rights.~~Rights ~~The~~Agreement ~~rights~~to ~~will~~extend ~~expire on~~ the ~~earliest~~final ofexpiration ~~(i) the close of business on June 2, 2024 (unless that~~ date ~~is advanced or extended by the Board~~ of ~~Directors), (ii)~~ the ~~time~~Rights atAgreement ~~which~~to ~~the~~noon, ~~rights~~New ~~are~~York ~~redeemed~~City ~~or exchanged under the Section 382 rights plan~~time, ~~(iii) the close of business~~ on ~~the~~March ~~day~~11, of2026. ~~repeal~~We ofmay ~~Section~~further ~~382~~extend of the ~~Internal~~term ~~Revenue Code or any successor statute and (iv) the close~~ of ~~business on~~ the ~~first~~Rights ~~day~~Agreement ofto ~~a taxable year of~~ the ~~Company~~extent necessary to ~~which~~provide ~~our Board of Directors determines~~ that ~~no NOLs may be carried forward. On May 16, 2024,~~ the ~~Company~~Rights ~~entered~~Agreement ~~into~~will ~~the~~terminate ~~Second~~immediately ~~Amendment~~prior to the ~~Section~~date ~~382~~on ~~Rights Agreement,~~ which ~~extends~~ the ~~expiration~~Merger ~~date~~is ~~of the Section 382 rights plan to the close of business on March 31, 2025~~consummated.

Rights Offering

On ~~September 1~~October 9, 2020, ~~our~~we ~~Board~~completed ofa ~~Directors~~rights ~~approved~~offering (the “Rights Offering”) pursuant to which we offered our existing stockholders the ability to purchase rights consisting of shares of our Series C Preferred Stock and shares of ~~the~~our ~~Company’s~~Common ~~common stock~~Stock. OnIn ~~October 9,~~connection ~~2020,~~with the Rights Offering ~~was completed and~~, ~~as a result,~~ we realized gross proceeds of approximately $43.6 million, and issued 40,000 shares of Series C Preferred Stock and 30,000,000 shares of ~~common~~Common ~~stock~~Stock. ~~such~~We ~~that there is~~ currently have an aggregate of 40,000 shares of Series C Preferred Stock and 74,214,603 shares of ~~common~~Common ~~stock~~Stock outstanding. (See Note 1211 to the Consolidated Financial Statements.)

~~With~~The ~~regard~~terms toof the Series C Preferred Stock provide, on an annual basis, that the Company’s Board of Directors may, at its sole discretion, cause a dividend with respect to the Series C Preferred Stock to be paid in cash to the holders in an amount equal to 3% of the liquidation preference as in effect at such time (initially $1,000 per share). If the dividend is not so paid in cash, the liquidation preference is adjusted and increased annually by an amount equal to 5% of the liquidation preference per share as in effect at such time, that is not paid in cash to the holders on such date. Holders of Series C Preferred Stock do not have any voting rights and the Series C Preferred Stock is not convertible into shares of our common stock. The initial liquidation value of the Series C Preferred Stock was $1,000 per share. On December 20, 2024, our Board declared a cash dividend of 3% of the liquidation preference ($42,483,286) of the Series C Preferred Stock, aggregating approximately $1,275,000 ($31.86 per share). Such dividend was paid on January 9, 2025 to the holders of record of our Series C Preferred Stock as of January 2, 2025.

We believe that the completion of the Rights Offering will not limit the use of our NOLs due to any Section 382 limitations.

As the Company’s Board declared dividends on the Series C Preferred Stock as of December 31, 2024 and 2023, the liquidation value at both December 31, 2024 and 2023 was $1,062 per share. (See Note 13 to the Consolidated Financial Statements.)

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that is not paid in cash to the holders on such date. Pursuant to the terms of the Merger Agreement, we are not permitted to pay any dividends to the holders of our Common Stock and we are not permitted to pay any cash dividends to the holders of our Series C Preferred Stock while the transactions contemplated by the Merger Agreement are pending.

The initial liquidation value of the Series C Preferred Stock was $1,000 per share. On December 20, 2024, our Board declared a cash dividend of 3% of the liquidation preference ($42,483,286) of the Series C Preferred Stock, aggregating approximately $1,275,000 ($31.86 per share). Such dividend was paid on January 9, 2025 to the holders of record of our Series C Preferred Stock as of January 2, 2025.

Due to the restrictions in the Merger Agreement, we are not permitted to pay a cash dividend on its Series C Preferred Stock for 2025. However, pursuant to the terms of the Series C Preferred Stock, if a cash dividend is not paid, we must accrete an increase in liquidation preference equal to 5% of the liquidation preference as in effect at such time. Accordingly, the Series C Preferred Stock was adjusted and increased by an amount equal to 5% of the liquidation preference per share ($42,483,400) as in effect at such time which aggregated approximately $2,124,000 ($53.10 per share) at December 31, 2025. Following such adjustment the liquidation preference of the Series C Preferred Stock at December 31, 2025 was approximately $44,607,400.

As described above, we have commenced the Series C Exchange Offer which allows holders of our Series C Preferred Stock to elect to exchange their shares of Series C Preferred Stock for shares of our Common Stock. Holders of Series C Preferred Stock that do not participate in the Series C Exchange Offer will not have the right to exchange their shares of Series C Preferred Stock into shares of Enzon’s Common Stock following the expiration of the Series C Exchange Offer. The Series C Exchange Offer is open to holders of Enzon’s Series C Preferred Stock that are held by holders other than Icahn Enterprises Holdings L.P., a Delaware limited partnership (“IEH”), and certain of its affiliates (collectively with IEH, the “IEH Parties”). Any shares of Enzon’s Series C Preferred Stock held by holders other than the IEH Parties that are not exchanged for shares of Enzon’s Common Stock in the Series C Exchange Offer will remain outstanding pursuant to their current terms. Pursuant to the terms of the Merger Agreement, the IEH Parties are required to exchange the shares of the Company’s Series C Preferred Stock into shares of the Company’s Common Stock prior to the completion of the Merger in a private exchange offer.

Since November 1, 2022, we have been able to redeem the Series C Preferred Stock at any time, in whole or in part, for an amount based on the liquidation preference per share as in effect at such time. Holders of Series C Preferred Stock have the right to demand that the Company redeem their shares of Series C Preferred Stock in the event that the Company experiences a change of control, such as the Merger. Under the terms of Enzon’s Series C Preferred Stock, we may redeem any outstanding shares of our Series C Preferred Stock for a cash amount equal to the aggregate liquidation preference of such shares at any time.

Liquidity and Capital Resources

Our current source of liquidity is our existing cash on hand, which includes the ~~approximately $43.6 million of~~ gross proceeds from our Rights Offering and the interest earned on that amount less certain operating expenses. (See Note 1311 to the Consolidated Financial Statements.) While we no longer have any research and development activities, we continue to retain rights to receive fees, royalties and milestone payments from existing licensing arrangements with other companies and, accordingly, we may be entitled to a share of milestone and royalty payments from ~~the~~our ~~approval~~few ~~and~~remaining ~~sale~~licensed ofpatents, ~~Vicineum~~but we do not expect any such amounts to be material. We believe that our existing cash and cash equivalents on hand will be sufficient to fund our operations, at least, through March ~~2026~~2027, if the Merger is not consummated. Our future royalty revenues are expected to be de minimis over the foreseeable future and we cannot assure you that we will receive any royalty, milestone or other revenues.

~~While~~We wehave ~~are~~entered ~~positioned~~into asthe aMerger ~~public~~Agreement ~~company~~with ~~acquisition~~Viskase ~~vehicle,~~for ~~where we can become~~ an ~~acquisition~~all-stock ~~platform~~transaction. toWe ~~potentially~~anticipate ~~utilize~~that ~~our~~we ~~NOLs~~will incontinue ~~an effort~~ to ~~enhance~~incur ~~stockholder~~transaction ~~value,~~costs wein ~~cannot~~connection ~~assure~~with ~~you~~the ~~that~~Merger. weIf ~~will~~the ~~succeed~~Merger inis ~~making~~not ~~acquisitions~~completed, ~~that are profitable or that~~ we will becontinue ~~able~~ to ~~utilize~~be ~~any~~positioned oras ~~all~~a ofpublic ~~our~~company ~~NOLs~~acquisition vehicle.

~~Net~~Cash ~~cash~~ used in operating activities ~~represents income~~, as adjusted for certain non-cash items including the effect of changes in operating assets and liabilities., ~~Net~~during ~~cash~~the ~~from~~year ~~operating~~ended ~~activities~~December ~~during~~31, ~~2024~~2025 was approximately $13,~~122~~010,000, as compared to net cash from operating activities during the year ended December 31, 2024 of $1,~~305~~122,000 ~~in 2023~~. The decrease ~~in net cash provided~~ of approximately $~~183~~4,132,000 was primarily attributable to ~~operating~~the ~~loss~~transaction costs of approximately $13,~~327~~955,000 in ~~2024~~the 2025 period related to the Merger for which there was no corresponding amount in the year ended December 31, ~~resulting~~2024 and the decrease in ~~net~~interest and dividend income of approximately $~~778~~531,000, decreasing to approximately $1,921,000 during ~~that~~the ~~period~~year ~~compared~~ended toDecember ~~net~~31, ~~income~~2025, offrom approximately $12,~~373~~452,000 during ~~2023~~the comparable period in 2024.

Cash used in financing activities represents cash dividends of approximately $1,275,000 paid to holders of the Company’s Series C Preferred Stock during 2024 and 2023. No cash was provided by investing activities in 2024 or 2023.15

~~The~~Table ~~net effect~~ of ~~the foregoing was a virtually unchanged cash position of approximately $46.9 and $47.0 million at December 31, 2024 and 2023, respectively.~~Contents

Cash used in financing activities represents cash dividends of approximately $1,275,000 paid to holders of the Company’s Series C Preferred Stock in 2025 relating to the 2024 period.

The net effect of the foregoing was a decrease of cash and cash equivalents of approximately $4,285,000 from approximately $46,859,000 for the year ended December 31, 2024 to approximately $42,574,000 for the year ended December 31, 2025.

Off-Balance Sheet Arrangements

We do not participate in transactions that generate relationships with unconsolidated entities or financial partnerships, such as entities often referred to as structured finance or special purpose entities, which would have been established for the purpose of facilitating off-balance sheet arrangements or other contractually narrow limited purposes. As of December 31, ~~2024~~2025, we were not involved in any off-balance sheet special purpose entity transactions.

Critical Accounting Policies and Estimates

A critical accounting policy is one that is both important to the portrayal of a company’s financial condition and results of operations and requires management’s most difficult, subjective or complex judgments, often as a result of the need to make estimates about the effect of matters that are inherently uncertain.

Our consolidated financial statements are presented in accordance with accounting principles that are generally accepted in the U.S. (“U.S. GAAP”). All applicable U.S. GAAP accounting standards effective as of December 31, ~~2024~~2025 have been taken into consideration in preparing the consolidated financial statements. The preparation of the consolidated financial statements requires estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses and related disclosures. Some of those estimates are subjective and complex, and, consequently, actual results could differ from those estimates. The following accounting policies and estimates have been highlighted as significant because changes to certain judgments and assumptions inherent in these policies could affect our consolidated financial statements.

We base our estimates, to the extent possible, on historical experience. Historical information is modified as appropriate based on current business factors and various assumptions that we believe are necessary to form a basis for making judgments about the carrying value of assets and liabilities. We evaluate our estimates on an ongoing basis and make changes when necessary. Actual results could differ from our estimates.

Income Taxes

Under the asset and liability method of accounting for income taxes, deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. A valuation allowance on net deferred tax assets is provided for when it is more likely than not that some portion or all of the deferred tax assets will not be realized. Accordingly, the Company is projecting pre-tax book loss through the expected closing date of the pending Merger with Viskase. Upon review of positive and negative evidence in determining a partial reversal of the valuation allowance, the Company has concluded that a full valuation allowance is necessary. Accordingly, our management will continue to assess the need for this valuation allowance and will make adjustments when appropriate. Additionally, our management believes that our NOLs will not be limited by any changes in our ownership as a result of the successful completion of the Merger (See Note 13 to the Consolidated Financial Statements).

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using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. A valuation allowance on net deferred tax assets is provided for when it is more likely than not that some portion or all of the deferred tax assets will not be realized. As of December 31, 2024, we believe, based on our projections, that a partial reversal of the valuation allowance is necessary. Interest rates may fluctuate throughout 2025, however, they are not expected to return to low rates of the past creating a projected taxable income position. Therefore, the Company will partially reverse the valuation allowances. We are positioned as a public company acquisition vehicle, where we can become an acquisition platform and potentially utilize our NOLs. We may acquire businesses, entities or revenue streams that could generate sufficient income so that we can utilize our approximately $101.4 million of federal NOLs. At this time, however, we cannot assure you that we will be successful in doing so. Accordingly, our management will continue to assess the need for this valuation allowance and will make adjustments when appropriate. Additionally, our management believes that our NOLs will not be limited by any changes in our ownership as a result of the successful completion of the Rights Offering (See Note 13 to the Consolidated Financial Statements).

We recognize the benefit of an uncertain tax position that we have taken or expect to take on the income tax returns we file if it is more likely than not that we will be able to sustain our position.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

As a smaller reporting company, we are not required to provide the information required by this item.

Item 8. Financial Statements and Supplementary Data

Financial statements and notes thereto appear on pages F-1 to F-16 of this Annual Report on Form 10-K.

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

None.

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Item 9A. Controls and Procedures

(a)Evaluation of Disclosure Controls and Procedures

Our ~~management, under the direction of our~~ Principal Executive Officer and Principal Financial Officer, who is the same individual, has evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) or 15d-15(e) under the Exchange Act of 1934, as amended (the “Exchange Act”), as of December 31, ~~2024~~2025. Disclosure controls and procedures are designed to ensure that information required to be disclosed in reports filed or submitted under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in SEC rules and forms and that such information is accumulated and communicated to management, including the Principal Executive Officer and Principal Financial Officer, to allow timely decisions regarding required disclosures. Based on that evaluation, our Principal Executive Officer and Principal Financial Officer concluded that our disclosure controls and procedures were effective as of December 31, ~~2024~~2025.

(b)Changes in Internal Control Over Financial Reporting

There were no changes in our internal control over financial reporting, as such term is defined in Rules 13a-15(f) or 15d-15(f) under the Exchange Act, during the quarter ended December 31, ~~2024~~2025 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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(c)Management’s Report on Internal Control over Financial Reporting

It is the responsibility of the management of Enzon Pharmaceuticals, Inc. and subsidiaries to establish and maintain adequate internal control over financial reporting (as defined in Rule 13a-15(f) under the Exchange Act). Internal control over financial reporting is a process designed by, or under the supervision of, our Principal Executive Officer, ~~and~~who is also our Principal Financial Officer, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles, and includes those policies and procedures that: (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of Enzon; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of consolidated financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of Enzon are being made only in accordance with authorizations of management and directors of Enzon; and (iii) provide reasonable assurance regarding the prevention or timely detection of unauthorized acquisition, use or disposition of Enzon’s assets that could have a material effect on the consolidated financial statements of Enzon.

~~Under~~Our ~~the~~Principal ~~supervision~~Executive ~~and~~Officer, ~~with~~who ~~the~~is ~~participation~~also of our ~~management,~~Principal weFinancial Officer, conducted an evaluation of the effectiveness of our internal control over financial reporting based on criteria established in “Internal Control—Integrated Framework - 2013” issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). ~~Our~~We ~~management~~ concluded that as of December 31, ~~2024~~2025 our internal control over financial reporting was effective based on those criteria.

(d)Limitations on the Effectiveness of Controls

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Therefore, even those systems determined to be effective can provide only reasonable assurance with respect to financial statement preparation and presentation.

Item 9B. Other Information

During the quarter ended December 31, ~~2024~~2025, none of the Company’s directors or officers (as defined in Rule 16a-1(f) of the Exchange Act) adopted or terminated any contract, instruction or written plan for the purchase or sale of Company securities that was intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) or any “non-Rule 10b5-1 trading arrangement”.

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Not applicable.

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PART III.

Item 10. Directors, Executive Officers and Corporate Governance

If we file a definitive proxy statement relating to our ~~2025~~2026 Annual Meeting of Stockholders with the SEC not later than 120 days after December 31, ~~2024~~2025, the information required by this Item 10 is incorporated herein by reference to such definitive proxy statement. However, if such definitive proxy statement is not filed with the SEC in such 120-day period, we will file an amendment to this Annual Report on Form 10-K with the SEC not later than 120 days after December 31, ~~2024~~2025 to include the information required by this Item 10.

The Company has adopted a code of ethics entitled “Code of Conduct and Corporate Values” that applies to the Company’s directors, officers, and employees (including its principal executive officer, principal financial officer, and principal accounting officer). We have posted our Code of Conduct and Corporate Values on our website (https://investors.enzon.com/corporate-governance) and will post on such website any amendments to, or waivers from, a provision of the Code of Conduct and Corporate Values applying to an executive officer or director when required by applicable SEC and OTC Markets rules and regulations.

Item 11. Executive Compensation

If we file a definitive proxy statement relating to our ~~2025~~2026 Annual Meeting of Stockholders with the SEC not later than 120 days after December 31, ~~2024~~2025, the information required by this Item 11 is incorporated herein by reference to such definitive proxy statement. However, if such definitive proxy statement is not filed with the SEC in such 120-day period, we will file an amendment to this Annual Report on Form 10-K with the SEC not later than 120 days after December 31, ~~2024~~2025 to include the information required by this Item 11.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

If we file a definitive proxy statement relating to our ~~2025~~2026 Annual Meeting of Stockholders with the SEC not later than 120 days after December 31, ~~2024~~2025, the information required by this Item 12 is incorporated herein by reference to such definitive proxy statement. However, if such definitive proxy statement is not filed with the SEC in such 120-day period, we will file an amendment to this Annual Report on Form 10-K with the SEC not later than 120 days after December 31, ~~2024~~2025 to include the information required by this Item 12.

If we file a definitive proxy statement relating to our ~~2025~~2026 Annual Meeting of Stockholders with the SEC not later than 120 days after December 31, ~~2024~~2025, the information required by this Item 13 is incorporated herein by reference to such definitive proxy statement. However, if such definitive proxy statement is not filed with the SEC in such 120-day period, we will file an amendment to this Annual Report on Form 10-K with the SEC not later than 120 days after December 31, ~~2024~~2025 to include the information required by this Item 13.

Item 14. Principal Accounting Fees and Services

If we file a definitive proxy statement relating to our ~~2025~~2026 Annual Meeting of Stockholders with the SEC not later than 120 days after December 31, ~~2024~~2025, the information required by this Item 14 is incorporated herein by reference to such definitive proxy statement. However, if such definitive proxy statement is not filed with the SEC in such 120-day period, we will file an amendment to this Annual Report on Form 10-K with the SEC not later than 120 days after December 31, ~~2024~~2025 to include the information required by this Item 14.

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PART IV

Item 15. Exhibits, Financial Statement Schedules

(a)(1), (a)(2) and (c). The response to this portion of Item 15 is submitted as a separate section of this report commencing on page F-1.

(a)(3) and (b). Exhibits (numbered in accordance with Item 601 of Regulation S-K).

Exhibit		Reference
Number	Description	No.
2.1˄	Agreement and Plan of Merger, dated as of June 20, 2025, by and between Enzon Pharmaceuticals, Inc., EPSC Acquisition Corp., and Viskase Companies, Inc.	(18)
3.1	Amended and Restated Certificate of Incorporation dated May 18, 2006, together with that Certificate of Amendment to the Amended and Restated Certificate of Incorporation dated July 13, 2010	(1)
3.2	Second Amended and Restated By-Laws effective March 11, 2011, as amended by Amendment No. 1 to the Second Amended and Restated By-Laws effective February 15, 2013	(2)
3.3	Certificate of Designation of Series A-1 Junior Participating Preferred Stock of Enzon Pharmaceuticals, Inc. filed with the Secretary of State of the State of Delaware on August 14, 2020	(4)
3.4	Certificate of Designation of Series C Non-Convertible Redeemable Preferred Stock of Enzon Pharmaceuticals, Inc., filed with the Secretary of State of the State of Delaware on September 21, 2020	(5)
3.5	First Amendment to the Second Amended and Restated By-Laws, effective February 24, 2022	(10)
4.1	Description of Enzon Pharmaceuticals, Inc.’s Registered Securities	+
4.2	Section 382 Rights Agreement, dated as of August 14, 2020, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company, which includes the Form of Certificate of Designation as Exhibit A, Form of Rights Certificate as Exhibit B and the Form of Summary of Rights as Exhibit C	(4)
4.3	First Amendment to the Section 382 Rights Agreement, dated as of June 4, 2021 and effective as of June 2, 2021, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company.	(6)
4.4	Second Amendment to the Section 382 Rights Agreement, dated as of May 16, 2024, by and between Enzon Pharmaceuticals, Inc., and Continental Stock Transfer & Trust Company	(12)
4.5	Third Amendment to the Section 382 Rights Agreement, dated as of March 31, 2025, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company	(13)
4.6	Fourth Amendment to the Section 382 Rights Agreement, dated as of August 13, 2025, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company	(14)
4.7	Fifth Amendment to the Section 382 Rights Agreement, dated as of September 30, 2025, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company	(15)
4.8	Sixth Amendment to the Section 382 Rights Agreement, dated as of December 23, 2025, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company	(16)
4.9	Seventh Amendment to the Section 382 Rights Agreement, dated as of January 30, 2026, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company	(17)
4.10	Eighth Amendment to the Section 382 Rights Agreement, dated as of February 27, 2026, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company	(21)
10.1	Development, License and Supply Agreement between Enzon, Inc. (now known as Enzon Pharmaceuticals, Inc.) and Schering Corporation dated November 14, 1990, as amended*	(3)
10.2	Amended and Restated 2013 Outside Director Compensation Plan**	(7)
10.3	Amended and Restated Exclusive IP Marketing Agreement, dated as of June 28, 2004, by and between Micromet AG and Enzon Pharmaceuticals, Inc.	(8)
10.4	Letter Agreement, dated January 30, 2019, between Servier IP UK Limited and Enzon Pharmaceuticals, Inc.	(8)
10.5	Investment Agreement, dated as of September 1, 2020, by and between Enzon Pharmaceuticals, Inc. and Icahn Capital LP	(9)
10.6	Independent Contractor Agreement, effective as of February 24, 2022, between Enzon Pharmaceuticals, Inc. and Richard L. Feinstein **	(10)
10.7	Form of Indemnification Agreement for members of the Board of Directors **	(11)
21.1	Subsidiaries of Registrant	+
10.8	Support Agreement, dated as of June 20, 2025, by and between Icahn Enterprises Holdings L.P. and certain of its affiliates, Enzon Pharmaceuticals, Inc. and Viskase Companies, Inc.	(18)
23.1	Consent of EisnerAmper LLP	+
31.1	Certification of Principal Executive Officer and Principal Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002	***
32.1	Certification of Principal Executive Officer and Principal Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002	***
101.INS	Inline XBRL Instance Document	+
101.SCH	Inline XBRL Taxonomy Extension Schema Document	+
101.CAL	Inline XBRL Calculation Linkbase Document	+
101.LAB	Inline XBRL Labels Linkbase Document	+
101.PRE	Inline XBRL Presentation Linkbase Document	+
101.DEF	Inline XBRL Definition Linkbase Document	+
104	Cover Page Interactive Data File (formatted as Inline XBRL and contained in the Interactive Data Files submitted as Exhibit 101)	+

+ Filed herewith

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10.9	First Amendment to Agreement and Plan of Merger, dated as of October 24, 2025, by and between Enzon Pharmaceuticals, Inc., EPSC Acquisition Corp., and Viskase Companies, Inc.	(19)
10.10	First Amendment to Support Agreement, dated as of October 24, 2025, by and between Icahn Enterprises Holdings L.P. and certain of its affiliates, Enzon Pharmaceuticals, Inc. and Viskase Companies, Inc.	(19)
19.1	Insider Trading Policy	(20)
21.1	Subsidiaries of Registrant	+
23.1	Consent of EisnerAmper LLP	+
31.1	Certification of Principal Executive Officer and Principal Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002	***
32.1	Certification of Principal Executive Officer and Principal Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002	***
101.INS	Inline XBRL Instance Document	+
101.SCH	Inline XBRL Taxonomy Extension Schema Document	+
101.CAL	Inline XBRL Calculation Linkbase Document	+
101.LAB	Inline XBRL Labels Linkbase Document	+
101.PRE	Inline XBRL Presentation Linkbase Document	+
101.DEF	Inline XBRL Definition Linkbase Document	+
104	Cover Page Interactive Data File (formatted as Inline XBRL and contained in the Interactive Data Files submitted as Exhibit 101)	+

+	Filed herewith

*	Portions of this exhibit have been redacted and filed separately with the SEC pursuant to a confidential treatment request.

**	Management contracts or compensatory plans and arrangements required to be filed pursuant to Item 601(b)(10)(ii)(A) or (iii) of Regulation S-K.

***

In accordance with Item 601(b)(32)(ii) of Regulation S-K and SEC Release Nos. 33-8238 and 34-47986, Final Rule: Management’s Reports on Internal Control Over Financial Reporting and Certification of Disclosure in Exchange Act Periodic Reports, the certifications furnished in Exhibit 32.1 and 32.1 hereto is deemed to accompany this Annual Report on Form 10-K and will not be deemed “filed” for purposes of Section 18 of the Exchange Act. Such certifications will not be deemed to be incorporated by reference into any filing under the Securities Act or the Exchange Act, except to the extent that the registrant specifically incorporates them by reference.

^˄	Certain of the exhibits and schedules to this Exhibit have been omitted in accordance with Regulation S-K Item 601(b)(2). The Registrant agrees to furnish a copy of all omitted exhibits and schedules to the SEC upon its request.

Referenced exhibit was previously filed with the SEC as an exhibit to the Company’s filing indicated below and is incorporated herein by reference to that filing:

(1)	Quarterly Report on Form 10-Q for the quarter ended June 30, 2010 filed August 9, 2010

(2)	Annual Report on Form 10-K for the year ended December 31, 2012 filed March 18, 2013

(3)	Annual Report on Form 10-K for the fiscal year ended June 30, 2002 filed on September 26, 2002

(4)	Current Report on Form 8-K filed August 14, 2020

(5)	Current Report on Form 8-K filed September 23, 2020

(6)	Current Report on Form 8-K filed June 8, 2021

(7)	Quarterly report on Form 10-Q for the quarter ended June 30, 2013 filed August 6, 2013

(8)	Annual Report on Form 10-K for the fiscal year ended December 31, 2018 filed on February 21, 2019

(9)	Current Report on Form 8-K filed September 1, 2020

Table of Contents

(10)	Annual Report on Form 10-K for the fiscal year ended December 31, 2021 filed on February 25, 2022

(11)	Quarterly report on Form 10-Q for the quarter ended March 31, 2022 filed April 26, 2022

(12)	Current Report on Form 8-K May 22, 2024

(13)	Current Report on Form 8-K filed with the SEC on April 1, 2025

(14)	Quarterly Report on Form 10-Q filed with the SEC on August 14, 2025

(15)	Current Report on Form 8-K filed with the SEC on September 30, 2025

(16)	Current Report on Form 8-K filed with the SEC on December 23, 2025

(17)	Company’s Current Report on Form 8-K filed with the SEC on January 30, 2026

(18)	Current Report on Form 8-K filed June 23, 2025

(19)	Current Report on Form 8-K filed October 24, 2025

(20)	Amendment to the Annual Report on Form 10-K for the fiscal year ended December 31, 2024 filed on April 28, 2025

(21)	Current Report on Form 8-K filed on February 27, 2026

Item 16. Form 10-K Summary

None.

2021

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	ENZON PHARMACEUTICALS, INC.
	(Registrant)
Dated: February 21, 2025	/s/ Richard L. Feinstein
Dated: March 2, 2026	/s/ Richard L. Feinstein
	Richard L. Feinstein
	Chief Executive Officer, Chief Financial Officer and Secretary
	(Principal Executive Officer and Principal Financial Officer)

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

Name	Title	Date
/s/ Richard L. Feinstein	Chief Executive Officer, Chief Financial Officer and Secretary	~~February~~March 212, ~~2025~~2026
Richard L. Feinstein	(Principal Executive Officer and Principal Financial Officer)
/s/ Randolph C. Read	Director (Chairman of the Board)	February 21, 2025

Randolph C. Read
/s/ Randolph C. Read	Director (Chairman of the Board)	March 2, 2026
/s/ Jordan Bleznick	Director	February 21, 2025
Randolph C. Read
Jordan Bleznick

/s/ Jordan Bleznick	Director	March 2, 2026
Jordan Bleznick

/s/ Jaffrey (Jay) A. Firestone	Director	~~February~~March 212, ~~2025~~2026
Jaffray A. Firestone

/s/ Stephen T. Wills	Director	~~February~~March 212, ~~2025~~2026
Stephen T. Wills

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ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

Index

		Page
		Page
Report of Independent Registered Public Accounting Firm (PCAOB ID 274)		F-2
Consolidated Financial Statements:
Consolidated Balance Sheets – December 31, 2024 and 2023		F-4
Consolidated Balance Sheets – December 31, 2025 and 2024		F-4
Consolidated Statements of Operations – Years Ended December 31, 2024 and 2023		F-5
Consolidated Statements of Operations – Years Ended December 31, 2025 and 2024		F-5
Consolidated Statements of Mezzanine Equity and Stockholders’ Equity – Years Ended December 31, 2024 and 2023		F-6
Consolidated Statements of Mezzanine Equity and Stockholders’ (Deficit) Equity – Years Ended December 31, 2025 and 2024		F-6
Consolidated Statements of Cash Flows –Years Ended December 31, 2024 and 2023		F-7
Consolidated Statements of Cash Flows –Years Ended December 31, 2025 and 2024		F-7
Notes to Consolidated Financial Statements		F-8

F-1

Table of Contents

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Directors and Stockholders of

Enzon Pharmaceuticals, Inc. and Subsidiaries

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Enzon Pharmaceuticals, Inc. and Subsidiaries (the “Company”) as of December 31, ~~2024~~2025 and ~~2023~~2024, and the related consolidated statements of operations, mezzanine equity and stockholders’ (deficit) equity, and cash flows for each of the years then ended, and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the consolidated financial position of the Company as of December 31, ~~2024~~2025 and ~~2023~~2024, and the consolidated results of their operations and their cash flows for each of the years then ended, in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (“PCAOB”) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of the critical audit matter does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

As discussed in Note 98 to the consolidated financial statements, the Company records a valuation allowance based on the assessment of the realizability of the Company’s deferred tax assets. For the year-ended December 31, ~~2024~~2025, the Company had deferred tax assets before valuation allowances of approximately $3229.47 million. As of December 31, ~~2024~~2025, the Company has recorded a valuation allowance of approximately $3229.47 million on the deferred tax assets, resulting in a deferred tax asset of $~~17,000~~0 as of December 31, ~~2024~~2025. In assessing the realizability of deferred tax assets, the Company must assess its tax planning strategies, enacted and effective tax law considerations, and whether sufficient future taxable income will be generated to support the realization of the existing deferred tax assets before expiration, using assumptions about Company-specific conditions and events.

We identified the assessment of realizability of deferred tax assets as a critical audit matter due to the significant judgement and estimation required by management in their assessment. This in turn led to a high degree of auditor subjectivity and significant audit effort was required in performing our procedures and evaluating audit evidence relating to estimates and assumptions made by management.

F-2

Table of Contents

Addressing the matter involved performing procedures and evaluating audit evidence, in connection with forming our overall opinion on the consolidated financial statements. We obtained an understanding and evaluated the design of controls over the valuation of deferred taxes. Our procedures also included, among others, an evaluation of: (a) the expiration dates of certain deferred tax assets, primarily federal and state net operating loss carryforwards, (b) whether the Company may have experienced an ownership change resulting in annual limitation of net operating loss carryforwards, and (c) the assumptions used by the Company to develop projections of future taxable income (loss) by income tax jurisdiction and tested the completeness and accuracy of the underlying data used in the projections. We compared the projections of future taxable income (loss) with the actual results of prior periods, as well as management’s consideration of current industry and economic trends. We also compared the projections of future taxable income (loss) with other forecasted financial information prepared by the Company. These procedures also included, among others, the involvement of professionals with specialized skill and knowledge to assist in considering whether management demonstrated their ability and intent in executing planned strategies, including the reasonableness of the application of enacted and effective tax law.

/s/ EisnerAmper LLP

We have served as the Company’s auditor since 2013.

EISNERAMPER LLP

Philadelphia, Pennsylvania

~~February~~March 212, ~~2025~~2026

F-3

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ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

(In thousands, except share and per share amounts)


	December 31,
	~~2024~~2025		~~2023~~2024
ASSETS

Current assets:
Cash and cash equivalents	$	4642,~~859~~574	$	4746,~~012~~859
Other current assets		~~293~~239		~~331~~293
Total current assets		4742,~~152~~813		47,~~343~~152
Deferred tax asset		17—		~~359~~17

Total assets	$	4742,~~169~~813	$	47,~~702~~169

LIABILITIES AND STOCKHOLDERS’ EQUITY
LIABILITIES, MEZZANINE EQUITY AND STOCKHOLDERS’ (DEFICIT) EQUITY

Current liabilities:
Accounts payable	$	331	$	331
Accrued expenses and other current liabilities		72400		~~108~~72
Dividends payable on Series C preferred stock		~~1,275~~—		1,275
Total current liabilities		~~1,678~~731		1,~~714~~678

Commitments and contingencies

Mezzanine equity:
Series C preferred stock - $0.01 par value, 40,000 shares authorized, issued and outstanding (liquidation value $1,062 per share ) at December 31, 2024 and 2023		42,483		42,483
Series C preferred stock - $0.01 par value, 40,000 shares authorized, issued and outstanding (liquidation value $1,115 per share and $1,062 per share) at December 31, 2025 and 2024, respectively		44,607		42,483

Stockholders’ equity:
Stockholders’ (deficit) equity:
Preferred stock - $0.01 par value, authorized 2,960,000 shares; no shares issued and outstanding at December 31, 2024 and 2023		—		—
Preferred stock - $0.01 par value, authorized 2,960,000 shares; no shares issued and outstanding at December 31, 2025 and 2024		—		—
Common stock - $0.01 par value, authorized 170,000,000 shares; issued and outstanding 74,214,603 shares at December 31, 2024 and 2023		742		742
Common stock - $0.01 par value, authorized 170,000,000 shares; issued and outstanding 74,214,603 shares at December 31, 2025 and 2024		742		742
Additional paid-in capital		7270,~~158~~034		7372,~~433~~158
Accumulated deficit		(6973,~~892~~301)		(7069,~~670~~892)
Total stockholders’ equity		3,008		3,505
Total stockholders’ (deficit) equity		(2,525)		3,008
Total liabilities, mezzanine equity and stockholders’ equity	$	47,169	$	47,702
Total liabilities, mezzanine equity and stockholders’ (deficit) equity	$	42,813	$	47,169

The accompanying notes are an integral part of these consolidated financial statements.

F-4

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ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except per share amounts)


	Year Ended December 31,
	~~2024~~2025		~~2023~~2024
Revenues:
Royalties and milestones, net	$	26—	$	—26
Total revenues		26—		—26

Operating expenses:
General and administrative		1,~~353~~356		1,~~044~~353
Total operating expenses		1,353		1,044
Transaction expenses		3,955		—
Total operating expenses		5,311		1,353

Operating loss		(15,~~327~~311)		(1,~~044~~327)
Interest and dividend income		21,~~452~~921		2,~~261~~452

Income before income tax (expense) benefit		1,125		1,217
(Loss) income before income tax expense		(3,390)		1,125

Income tax (expense) benefit		(347)		156
Income tax expense		(19)		(347)

Net income		778		1,373
Net (loss) income		(3,409)		778
Dividends on Series C preferred stock		(1,275)		(1,275)
Dividends on Series C Preferred Stock		(2,124)		(1,275)
Net (loss) income available to common shareholders	$	(497)	$	98
Net loss available to common shareholders	$	(5,533)	$	(497)

(Loss) income per common share
Loss per common share
Basic and diluted	$	(0.0107)	$	(0.0001)
Weighted average number of common shares
Basic and diluted		74,215		74,215

The accompanying notes are an integral part of these consolidated financial statements.

F-5

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ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF MEZZANINE EQUITY AND STOCKHOLDERS’ (DEFICIT) EQUITY

(In thousands)


	Mezzanine Equity – Series C
	Preferred Stock			Common Stock			Additional				Total
	Number of	Par		Number of	Par		Paid-in		Accumulated		Stockholders’
	Shares	Value		Shares	Value		Capital		Deficit		(Deficit) Equity
Balance, December 31, 2022	40		42,483	74,215		742		74,708		(72,043)		3,407
Balance, December 31, 2023	40	$	42,483	74,215	$	742	$	73,433	$	(73,301)	$	(3,505)
Net income	—		—	—		—		—		1,373		1,373
Preferred stock dividend declared	—		—	—		—		(1,275)		—		(1,275)
Balance, December 31, 2023	40		42,483	74,215		742		73,433		(70,670)		3,505
Net income	—		—	—		—		—		778		778
Preferred stock dividend declared	—		—	—		—		(1,275)		—		(1,275)
Balance, December 31, 2024	40	$	42,483	74,215	$	742	$	72,158	$	(69,892)	$	3,008
Net loss	—		—	—		—		—		(3,409)		(3,409)
Preferred stock dividend accretion	—		2,124	—		—		(2,124)		—		(2,124)
Balance, December 31, 2025	40	$	44,607	74,215	$	742	$	70,034	$	(73,301)	$	(2,525)

The accompanying notes are an integral part of these consolidated financial statements.

F-6

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ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands)


	Year Ended December 31,
	~~2024~~2025		~~2023~~2024
Cash flows from operating activities:
Cash flows (used in) provided by operating activities:
Net income	$	778	$	1,373
Net (loss) income	$	(3,409)	$	778
Adjustments to reconcile net income to net cash provided by in operating activities:
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Deferred income taxes		~~342~~17		~~(157)~~342
Changes in operating assets and liabilities
Decrease in other current assets		3854		7438
(Decrease) increase in accrued expenses and other current liabilities		(36)		15
Increase (decrease) in accrued expenses and other current liabilities		328		(36)
Net cash provided by operating activities		1,122		1,305
Net cash (used in) provided by operating activities		(3,010)		1,122

Cash flows from financing activities:
Preferred stock dividend payments		(1,275)		(1,275)
Net cash used in financing activities		(1,275)		(1,275)

Net (decrease) increase in cash		(153)		30
Net decrease in cash		(4,285)		(153)
Cash and cash equivalents at beginning of year		4746,~~012~~859		4647,~~982~~012
Cash and cash equivalents at end of year	$	4642,~~859~~574	$	4746,~~012~~859

Non-cash financing activities:
Declaration of dividend for Series C Preferred Stock	$	~~1,275~~—	$	1,275
Accretion of 5% liquidation preference for Series C Preferred Stock	$	2,124	$	—

The accompanying notes are an integral part of these consolidated financial statements.

F-7

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ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(1) Description of Business

Enzon Pharmaceuticals, Inc. (together with its subsidiaries, the “Company,” “Enzon,” “we” or “us”) is positioned as a public company acquisition vehicle,. ~~where~~The itCompany ~~can~~maintains ~~become~~its anprincipal ~~acquisition~~executive ~~platform~~offices ~~and~~at ~~potentially~~20 ~~utilize~~Commerce ~~its~~Drive, ~~net~~Suite ~~operating~~135, ~~loss~~Cranford, ~~carryforwards~~New ~~(“NOLs”)~~Jersey in07016 anthrough ~~effort~~a toservice ~~enhance~~agreement ~~stockholder~~with ~~value.~~Regus Management Group, LLC.

InHistorically, ~~September~~we ~~2020,~~have ~~the~~received ~~Company~~royalty ~~initiated~~revenues afrom ~~rights~~licensing ~~offering~~arrangements ~~for~~with ~~its~~other ~~common~~companies ~~and~~primarily ~~preferred~~related ~~stock~~to ~~(see~~sales ~~below~~of ~~and~~certain ~~Note~~drug 13products tothat ~~our~~utilized ~~Condensed~~Enzon’s ~~Consolidated~~proprietary ~~Financial~~technology. ~~Statements)~~For more than ten years, ~~which~~we ~~closed~~have inhad ~~October~~no ~~2020,~~clinical operations and itlimited ~~realized~~corporate ~~$43~~operations.6 ~~million~~We inpreviously ~~gross~~were ~~proceeds.~~a ~~This~~party ~~has~~to ~~enabled~~a ~~the~~marketing ~~Company~~agreement relating to ~~embark~~the ondrug ~~its~~Vicineum, ~~plan~~which, toif approved, could have potentially ~~realize~~generated milestone and royalty payments to us in the ~~value~~future. ofHowever, ~~its~~our ~~more~~licensee ~~than~~for ~~$100~~this ~~million~~drug ~~NOLs~~was canceled by ~~acquiring~~the ~~businesses~~counterparty orto ~~assets.~~the Tomarketing ~~protect~~agreement ~~the~~and ~~NOLs,~~our inpatent ~~August~~for ~~2020~~Vicineum has since expired. Accordingly, ~~the~~we ~~Company’s~~do ~~Board~~not ofbelieve ~~Directors~~any ~~(the~~future ~~“Board”)~~revenue ~~adopted~~will abe ~~Section~~earned ~~382~~from ~~rights~~this ~~plan~~product ~~(see~~or ~~Note~~that 12if toany ~~our~~such ~~Condensed~~revenue ~~Consolidated~~is ~~Financial~~earned ~~Statements)~~it will be material.

~~Historically~~Previously, over the ~~Company~~last ~~had~~few ~~received~~years, ~~royalty~~the ~~revenues~~Board ~~from~~of ~~licensing~~Directors ~~arrangements~~of ~~with~~the ~~other~~Company ~~companies~~(the ~~primarily~~“Board”) ~~related~~and tothe ~~sales~~Company’s ofmanagement ~~certain~~have ~~drug~~been ~~products~~actively ~~that~~involved ~~utilized~~in ~~Enzon’s~~pursuing, ~~proprietary~~sourcing, ~~technology.~~reviewing Inand ~~recent~~evaluating ~~years,~~various ~~the~~potential ~~Company~~acquisition ~~has~~transactions ~~had~~consistent nowith ~~clinical~~its ~~operations~~strategy. ~~and~~Over ~~limited~~that ~~corporate~~time ~~operations.~~period, ~~Enzon~~the ~~has~~Company’s amanagement ~~marketing~~and ~~agreement~~members inof the ~~drug~~Board ~~Vicineum,~~have ~~which,~~engaged ifin ~~approved,~~numerous ~~will,~~discussions ~~potentially,~~with ~~generate~~principals ~~milestone~~of individual companies and ~~royalty~~financial ~~payments~~advisors toon itbehalf inof ~~the~~various ~~future.~~individual ~~Enzon~~companies ~~cannot~~relating ~~assure~~to ~~you~~potential ~~that~~transactions itwith ~~will~~such ~~earn~~parties, ~~material~~and ~~future~~have ~~royalties~~regularly orevaluated ~~milestones~~the Company’s strategic alternatives.

~~The~~On ~~Board~~June 20, 2025, the Company, EPSC Acquisition Corp., a Delaware corporation and a wholly owned subsidiary of the Company’s ~~management~~(“Merger ~~are~~Sub”), ~~actively~~and ~~involved~~Viskase inCompanies, ~~pursuing~~Inc. (“Viskase”) entered into an Agreement and Plan of Merger, ~~sourcing~~which was amended on October 24, ~~reviewing~~2025 (as amended, the “Merger Agreement”). Upon the terms and ~~evaluating~~subject ~~various~~to ~~potential~~the ~~acquisition~~satisfaction ~~transactions~~or ~~consistent~~waiver of the conditions described in the Merger Agreement, at the effective time of the merger, Merger Sub will be merged with ~~its~~and ~~strategy~~into Viskase, with Viskase as the surviving entity following the merger as a wholly owned subsidiary of Enzon (the “Merger”). ~~The~~Following ~~Company~~consummation of the Merger, it is anticipated that Enzon’s ~~management~~pre-closing ~~and~~stockholders, ~~Board~~including ~~have~~holders ~~made~~of aEnzon’s ~~number~~Series C Non-Convertible Redeemable Preferred Stock (the “Series C Preferred Stock”), will hold 45% of ~~contacts~~the outstanding shares of Enzon’s Common Stock following the Merger, and ~~engaged~~Viskase’s incurrent ~~discussions~~stockholders ~~with~~will ~~principals~~hold 55% of ~~individual~~the ~~companies~~outstanding shares of Enzon’s Common Stock following the Merger. If the Merger is completed, Enzon Pharmaceuticals, Inc. will change its name to “Viskase Holdings, Inc.” and ~~financial~~its ~~advisors~~common stock will be quoted on ~~behalf~~the OTCQB tier of ~~various~~the ~~individual~~OTC ~~companies~~Markets Group, ~~while~~Inc., ~~continuing~~although pursuant to ~~evaluate~~the ~~potential~~rules ~~transactions.~~of Tothe ~~date~~OTCQB, noEnzon ~~actionable~~is ~~transactions~~required ~~have~~to ~~been~~re-apply ~~initiated~~to the OTCQB following such change of control transaction. (See Note 13.)

The Company has a marketing agreement with Micromet AG, now part of Amgen, Inc. (the “Micromet Agreement”), pursuant to which it may be entitled to certain milestone and royalty payments if Vicineum, a drug that was being developed by Sesen, Inc., (Sesen”) is approved for the treatment of non-muscle invasive bladder cancer. Sesen announced that it had completed a merger with Carisma Therapeutics Inc. (“Carisma”) and that the combined company will focus on the advancement of Carisma’s proprietary cell therapy for the treatment of cancer and other disorders and that that it intends to seek a partner for the further development of Vicineum.

During the 2nd quarter of 2024, we received a license maintenance fee of approximately $26,000 from Amgen, Inc. in payment of a worldwide, royalty-free non-exclusive right to license Vicineum. The fee represents half of the amount paid by Viventia Biotech (Barbados) Inc. (“Viventia”), part of Sesen, on an annual basis for the continued right to license Vicineum. The Company did not receive any license maintenance fees in 2023.

In August 2020, the Board adopted a Section 382 rights plan and declared a dividend distribution of one right for each outstanding share of the Company’s common stock to stockholders of record at the close of business on August 24, 2020. (See Note 11 to the Consolidated Financial Statements.)

In September 2020, the Board approved a Rights Offering (the “Rights Offering”), by which the Company distributed, at no charge to all holders of its common stock on September 23, 2020 (the “Record Date”), transferable subscription rights to purchase units (“Units”) at a subscription price per Unit of $1,090. In the Rights Offering, each stockholder on the Record Date received one subscription right for every share of common stock owned on the Record Date. For every 1,105 subscription rights held, a stockholder was entitled to purchase one Unit at the subscription price. Each Unit consisted of one share of newly designated Series C Preferred Stock, par value $0.01 per share, and 750 shares of the Company’s common stock. The subscription period for the Rights Offering ended on October 9, 2020.

As a result of the sale of all 40,000 Units available for purchase in the Rights Offering, the Company received approximately $43.6 million of gross proceeds and had 40,000 shares of Series C Preferred Stock outstanding and an aggregate of 74,214,603 shares of common stock outstanding following the Rights Offering. (See Note 12 to the Consolidated Financial Statements.)

On an annual basis, the Board may, at its sole discretion, cause a dividend with respect to the Series C Preferred Stock to be paid in cash to the holders in an amount equal to 3% of the liquidation preference as in effect at such time (initially $1,000 per share). If the dividend is not so paid in cash, the liquidation preference is adjusted and increased annually by an amount equal to 5% of the liquidation preference per share as in effect at such time, that is not paid in cash to the holders on such date. The Board did not declare a dividend as of December 31, 2021 and, at December 31, 2021 the liquidation value of the Series C Preferred Stock was $1,062 per share. On December 29, 2022, the Board declared a cash dividend of 3% on the Series C Preferred Stock, aggregating $1,275,000 or

F-8

Table of Contents

ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

$31.86 per share. Accordingly, the cumulative liquidation value of the Series C Preferred Stock remained at approximately $42,483,000 ($1,062 per share) on December 31, 2022. On December 28, 2023, the Board declared a cash dividend of 3% on the Series C Preferred Stock, aggregating approximately $1,275,000 or $31.86 per share. Accordingly, the cumulative liquidation value of the Series C Preferred Stock remained at approximately $42,483,000 ($1,062 per share) on December 31, 2023. The dividend was paid on January 17, 2024 to the holders of record of the Company’s Series C Preferred Stock as of January 10, 2024. (See Note 13 to the Consolidated Financial Statements.) On December 20, 2024, the Board declared a cash dividend of 3% on the Series C Preferred Stock, aggregating approximately $1,275,000 or $31.86 per share. Accordingly, the cumulative liquidation value of the Series C Preferred Stock remained at approximately $42,483,000 ($1,062 per share) on December 31, 2024. The dividend was paid on January 9, 2025 to the holders of record of the Company’s Series C Preferred Stock as of January 2, 2025. (See Note 13 to the Consolidated Financial Statements.)

The Company maintains its principal executive offices at 20 Commerce Drive, Suite 135, Cranford, New Jersey 07016 through a service agreement with Regus Management Group, LLC.

(2) Summary of Significant Accounting Policies

Principles of Consolidation

The consolidated financial statements include the accounts of Enzon Pharmaceuticals, Inc. and its wholly owned subsidiaries, SCA Ventures, Inc. and EPSC Acquisition Corp. All intercompany balances and transactions have been eliminated as part of the consolidation.

Use of Estimates

The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. These estimates include legal and contractual contingencies and income taxes. Although management bases its estimates on historical experience, relevant current information and various other assumptions that are believed to be reasonable under the circumstances, actual results could differ from these estimates.

Financial Instruments and Fair Value

The carrying values of cash and cash equivalents, royalty receivable, other current assets, accounts payable, accrued expenses and other current liabilities in the Company’s consolidated balance sheets approximated their fair values at December 31, ~~2024~~2025 and ~~2023~~2024 due to their short-term nature. As of December 31, ~~2024~~2025 and ~~2023~~2024, the Company held cash equivalents aggregating approximately $4642.84 million and $46.58 million, respectively.

~~Revenue Recognition~~F-8

Royalty revenues from the Company’s agreements with third parties and pursuant to the sale of the Company’s former specialty pharmaceutical business are recognized when the Company can reasonably determine the amounts earned. In most cases, this will be upon notification from the third-party licensee, which is typically during the quarter following the quarter in which the sales occurred. The Company does not participate in the selling or marketing of products for which it receives royalties. Because the Company records revenue only when collection is assured, no provision for uncollectible accounts is established upon recognition of revenues.

Contingent payments with third parties and pursuant to the sale of the Company’s former specialty pharmaceutical business are recognized as income when the milestone has been achieved and collection is assured, such payments are non-refundable and no further effort is required on the part of the Company or the other party to complete the earnings process.

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be realized. The effect of a change in tax rates or laws on deferred tax assets and liabilities is recognized in operations in the period that includes the

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

~~enactment~~Revenue ~~date of the rate change. A valuation allowance is established to reduce the deferred tax assets to the amounts that are more likely than not to be realized from operations.~~Recognition

Royalty revenues, if any, from the Company’s agreements with third parties and pursuant to the sale of the Company’s former specialty pharmaceutical business are recognized when the Company can reasonably determine the amounts earned. In most cases, this will be upon notification from the third-party licensee, which is typically during the quarter following the quarter in which the sales occurred. The Company does not participate in the selling or marketing of products for which it receives royalties. Because the Company records revenue only when collection is assured, no provision for uncollectible accounts is established upon recognition of revenues.

Contingent payments, if any, with third parties and pursuant to the sale of the Company’s former specialty pharmaceutical business are recognized as income when the milestone has been achieved and collection is assured, such payments are non-refundable and no further effort is required on the part of the Company or the other party to complete the earnings process.

Income Taxes

Tax benefits of uncertain tax positions are recognized only if it is more likely than not that the Company will be able to sustain a position taken on an income tax return. The Company has no liability for uncertain tax positions. Interest and penalties, if any, related to unrecognized tax benefits would be recognized as income tax expense.

(3) Recent Accounting Pronouncements

In ~~November~~December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-0709, ~~Segment~~Income ~~Reporting~~Taxes (Topic ~~280~~740): Improvements to ~~Reportable~~Income ~~Segment~~Tax Disclosures,. ~~requiring~~This ASU requires public entities, ~~to disclose information about their reportable segments’ significant expenses and other segment items~~ on an ~~interim and~~ annual basis., ~~Public~~to ~~entities~~provide ~~with~~disclosure aof ~~single~~specific ~~reportable~~categories ~~segment~~in ~~are~~the ~~required~~rate toreconciliation, ~~apply~~as ~~the~~well as disclosure ~~requirements~~of inincome ~~ASU~~taxes ~~2023-07,~~paid asdisaggregated ~~well~~by asjurisdiction. ~~all~~ASU ~~existing~~2023-09 ~~segment~~is ~~disclosures~~effective ~~and~~for ~~reconciliation~~fiscal ~~requirements~~years inbeginning ~~ASC~~after ~~280~~December on15, an2024, ~~interim~~with ~~and~~early ~~annual~~adoption ~~basis~~permitted. ~~The~~This ~~Company adopted~~ ASU ~~2023-07~~was ~~during~~adopted ~~the~~effective ~~year~~January ~~ended December 31~~1, ~~2024~~2025. ~~See~~The ~~Note~~Company 14incorporated in the ~~accompanying~~required ~~notes~~disclosures toin ~~the~~Note ~~consolidated~~8 ~~financial~~on ~~statements~~a retrospective basis.

In November 2024, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2024-03, Reporting Comprehensive Income (Topic 220): Disaggregation of Income Statement Expenses which requires disaggregated disclosure of income statement expenses for public entities. The ASU does not change the expense captions an entity presents on the face of the income statement; rather, it requires disaggregation of certain expense captions into specified categories in disclosures within the footnotes to the financial statements. ASU 2024-03 is effective for the Company in its annual reporting on January 1, 2027. The Company does not plan to adopt this standard early. The Company is currently evaluating the effect that the adoption of ASU 2024-03 will have on the Company’s disclosures.

Other recent Accounting Standards Updates issued by the FASB and guidance issued by the Securities and Exchange Commission (“SEC”) did not, or are not believed by management to, have a material effect on the Company’s present or future consolidated financial statements.

(4) Accounts Payable, Accrued Expenses and Dividends Payable on Series C Preferred Stock

Prior to 2017, the Company’s primary source of royalty revenues was derived from sales of PegIntron, which is marketed by Merck & Co., Inc. (“Merck”). At December 31, ~~2022~~2021, we recorded a liability to Merck of approximately $331,000 (net of a royalty interest of 25% held by DRI Capital, Inc.), based primarily on Merck’s assertions regarding recoupments related to prior returns and rebates. During the ~~years~~following ~~ended December 31~~years, ~~2024 and 2023,~~ no additional royalties or recoupments related to PegIntron were reported by Merck. As such, as asserted by Merck, the Company’s recorded liability to Merck remained at $331,000 at December 31, ~~2024~~2025 and ~~2023~~2024. The Company will receive no future royalties or chargebacks from Merck.

~~Accrued expenses and other current liabilities consisted of the following as of December 31, 2024 and 2023 (in thousands):~~F-9

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Accrued expenses and other current liabilities consisted of the following as of December 31, 2025 and 2024 (in thousands):

On December 20, 2024, the Board declared a cash dividend of 3% of the liquidation preference ($42,483,286) of the Series C Preferred Stock, aggregating approximately $1,275,000 ($31.86 per share). Such dividend was accrued at December 31, 2024 and paid on January 9, 2025.


		December 31,			December 31,
		2025			2024
Professional and consulting fees		$	33		$	67
Accrued transaction costs			358			—
Other			9			5
		$	400		$	72

Due to the restrictions in the Merger Agreement, the Company was not permitted to pay a cash dividend on its Series C Preferred Stock for 2025. Accordingly, the liquidation preference was increased by an amount equal to 5% per share as in effect at such time, aggregating approximately $2,124,000 ($53.10 per share), to $44,607,452.

On December 20, 2024, the Board declared a cash dividend of 3% on the Series C Preferred Stock, aggregating approximately $1,275,000. At December 31, 2024, this amount was recorded as a dividend payable. The dividend was paid on January 9, 2025 to the holders of record of the Company’s Series C Preferred Stock as of January 2, 2025.

(5) Stockholders’ Equity

Preferred Stock

The Company has authorized 3,000,000 shares of preferred stock in one or more series of which, at December 31, ~~2024~~2025 and ~~2023~~2024, 40,000 shares have been issued, are outstanding and are designated as Series C Preferred Stock in connection with the Rights Offering discussed in Note 1411 and 100,000 shares have been designated as Series A-1 Junior Participating Preferred Stock in connection with the August 2020 Section 382 rights plan discussed in Note 1110.

Common Stock

As of December 31, 2024, the Company reserved 9,818,392 shares of its common stock for the non-qualified and incentive stock plans.

(6) Cash Dividend

NoPursuant ~~dividend~~to on the ~~shares~~terms of the Merger Agreement, the Company’s ~~common~~is ~~stock~~not ~~has~~permitted ~~been~~to ~~paid~~pay any dividends to the holders of its Common Stock or ~~declared~~to ~~during~~pay any cash dividends to the ~~years~~holders ~~ended~~of ~~December~~its ~~31,~~Series ~~2024~~C ~~and~~Preferred ~~2023~~Stock while the transactions contemplated by the Merger Agreement are pending.

No dividend on the shares of the Company’s common stock has been paid or declared during the years ended December 31, 2025 and 2024.

Due to the restrictions in the Merger Agreement, the Company was not permitted to pay a cash dividend on its Series C Preferred Stock for 2025. However, pursuant to the terms of the Series C Preferred Stock, if a cash dividend is not paid, the Company must accrete an increase in liquidation preference equal to 5% of the liquidation preference as in effect at such time. Accordingly, the Series C Preferred Stock was adjusted and increased by an amount equal to 5% of the liquidation preference ($42,483,402) as in effect at such time, which aggregated approximately $2,124,000 ($53.10 per share) at December 31, 2025. Following such adjustment the liquidation preference of the Series C Preferred Stock at December 31, 2025 was approximately $44,607,452 ($1,115 per share).

On December 20, 2024, the Board declared a cash dividend of 3% on the Series C Preferred Stock, aggregating approximately $1,275,000 or $31.86 per share. Accordingly, the cumulative liquidation value of the Series C Preferred Stock was approximately $42,483,000 ($1,062 per share) on December 31, 2024. The dividend was paid on January 9, 2025 to the holders of record of the Company’s Series C Preferred Stock as of January 2, 2025 (See Note 11 to the Consolidated Financial Statements).

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

On December 20, 2024, the Board declared a cash dividend of 3% on the Series C Preferred Stock, aggregating approximately $1,275,000 or $31.86 per share. Accordingly, the cumulative liquidation value of the Series C Preferred Stock was approximately $42,483,000 (~~$1,062 per share~~7) ~~on December 31, 2024. The dividend was paid on January 9, 2025 to the holders of record of the Company’s Series C Preferred Stock as of January 2, 2025~~ (~~See~~Loss) ~~Note~~Income 13Per toCommon ~~the Consolidated Financial Statements).~~Share

OnBasic ~~December~~and ~~28,~~diluted ~~2023~~loss per common share (EPS) is calculated by dividing net (loss) income, ~~the~~less ~~Board~~any ~~declared~~dividends, aaccretion ~~cash~~or ~~dividend~~reduction ofor 3%redemption on the Company’s Series C Preferred Stock, ~~aggregating~~by ~~approximately~~the ~~$1,275,000~~weighted oraverage ~~$31.86~~number ~~per~~of ~~share.~~common ~~Accordingly,~~shares outstanding during the ~~cumulative~~reported ~~liquidation~~period. ~~value~~During each of the ~~Series~~years Cended ~~Preferred~~December ~~Stock~~31, ~~was~~2025 ~~approximately~~and ~~$42~~2024,~~483~~ there were no common stock equivalents. Nor are there any other equity-based incentives outstanding during any of the periods reported hereunder,~~000~~ ~~($1~~and accordingly,~~062~~ ~~per~~basic ~~share)~~and ondiluted ~~December~~EPS ~~31,~~are ~~2023.~~the ~~The~~same ~~dividend~~throughout. ~~was~~As ~~paid~~discussed onin ~~January~~Note 1713, ~~2024~~the Company has entered into the Merger Agreement. Pursuant to such agreement the ~~holders~~Company ofwill ~~record~~be initiating a 1-for-100 reverse split of its common stock prior to closing the ~~Company’s~~Merger. ~~Series~~(Loss) Cincome ~~Preferred~~per ~~Stock~~common share information is as offollows ~~January~~(in 10thousands, ~~2024~~except ~~(See~~per ~~Note~~share 13amounts) tofor the ~~Consolidated~~years ~~Financial~~ended ~~Statements~~December 31, 2025 and 2024 and pro forma (unaudited). for the years ended December 31, 2025 and 2024:

(7) Income (Loss) Per Common Share


		2025			2024
(Loss) Income per Common Share – Basic and Diluted
Net (loss) income for year		$	(3,409)		$	778
Dividends on Series C preferred stock			(2,124)			(1,275)
Net loss available to common shareholders		$	(5,533)		$	(497)

Weighted-average number of common shares outstanding			74,215			74,215

Basic and diluted loss per common share		$	(0.07)		$	(0.01)

(Loss) Income per Common Share – Basic and Diluted - Pro Forma (unaudited)
Pro forma weighted-average number of common shares outstanding			742			742

Pro forma basic and diluted loss per common share		$	(7.46)			(0.67)

Basic earnings (loss) per common share (EPS) is calculated by dividing net income (loss), less any dividends, accretion or reduction or redemption on the Company’s Series C Preferred Stock, by the weighted average number of common shares outstanding during the reported period. Restricted stock awards and restricted stock units (collectively, “nonvested shares”) are not considered to be outstanding shares until the service or performance vesting period has been completed.

The diluted earnings per common share calculation would normally involve adjusting both the denominator and numerator as described here if the effect is dilutive.

For purposes of calculating diluted earnings per common share, the denominator normally includes both the weighted-average number of shares of common stock outstanding and the number of common stock equivalents if the inclusion of such common stock equivalents is dilutive. Dilutive common stock equivalents potentially include stock options and nonvested shares using the treasury stock method and shares issuable under the employee stock purchase plan. During each of the years ended December 31, 2024 and 2023, there were no common stock equivalents. Because there were no stock options or other equity - based incentives outstanding in the 2024 and 2023 periods the Company had no common stock equivalents during the years ended December 31, 2024 and 2023. Income (loss) per common share information was as follows (in thousands, except per share amounts) for the years ended December 31, 2024 and 2023:


	2024		2023
(Loss) Income per Common Share – Basic and Diluted
Net income for year	$	778	$	1,373
Dividends on Series C preferred stock		(1,275)		(1,275)
Net (loss) income available to common shareholders	$	(497)	$	98

Weighted-average number of common shares outstanding		74,215		74,215

Basic and diluted (loss) income per common share	$	(0.01)	$	0.00

(8) Income Taxes

The components of (loss) income before income taxes are as follows (in thousands):

(8) Stock Options


		Year Ended December 31,
		2025			2024
United States		$	(3,390)		$	1,125
Foreign			—			—
(Loss) income before taxes		$	(3,390)		$	1,125

All of the Company’s incentive, stock options and equity-based compensation plans were terminated effective February 24, 2022 and, as such, there will be no further grants made pursuant these plans. There were no options outstanding at December 31, 2024 and 2023.

The components of the income tax provision are summarized as follows (in thousands):


	Year Ended December 31,
	2025		2024
Current:
Federal	$	—	$	—
State		2		5
Total current		2		5
Deferred:
Federal		13		255
State		4		87
Total deferred		17		342

Income tax expense	$	19	$	347

The state jurisdiction that makes up the majority (greater than 50%) of the state income tax category is New Jersey.

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ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The cash paid for income taxes (9net of refunds) ~~Income~~ ~~Taxes~~during the year are as follows (in thousands):

The components of the income tax provision (benefit) are summarized as follows (in thousands):


	Year Ended December 31,
	~~2024~~2025		~~2023~~2024
Current:
Federal	$	—	$	—
State and foreign		5		1
New Jersey		2		2
Total current		5		1
Total income taxes paid	$	2	$	2
Deferred:
Federal		255		(117)
State		87		(40)
Total deferred		342		(157)

Income tax expense (benefit)	$	347	$	(156)

The following table represents the reconciliation between the reported income taxes and the income taxes that would be computed by applying the federal statutory rate (21% for years ended December 31, ~~2024~~2025 and ~~2023~~2024) to income before taxes (in thousands):


	Year Ended December 31,
	~~2024~~2025		~~2023~~		2024
Income tax provision at federal statutory rate	$	236	$	256
	$		%		$		%
Add (deduct) effect of:
U.S. Federal Statutory Tax Rate	$	(712)	21.0	%	$	236	21.0	%
State income taxes, net of federal tax		84		87
State and Local Income Taxes, Net of Federal Income Tax Effect		6	(0.2)	%		88	7.8	%
Expiration of federal research and development credits		1,694		1,637
Tax Credits
Change in valuation allowance		(1,667)		(2,136)
Expiration of research and development credit		624	(18.4)	%		1,694	150.6	%

Change in Valuation Allowance		(2,649)	78.1	%		(1,674)	(148.8)	%
Income tax expense (benefit)	$	347	$	(156)
Nondeductible Items
Transaction costs		831	(24.5)	%		—	0.0	%
Other
Expiration of federal net operating loss		1,920	(56.6)	%		—	0.0	%
Other		(1)	0.0	%		3	0.2	%
Total income tax expense	$	19	(0.6)	%	$	347	30.8	%

No federal income tax expense was incurred in relation to normal operating results.

As of December 31, ~~2024~~2025 and ~~2023~~2024, the cumulative tax effects of temporary differences that give rise to the deferred tax assets were as follows (in thousands):


	December 31,		December 31,
	~~2024~~2025		~~2023~~2024
Deferred tax assets:
Federal and state net operating loss carryforward	$	2220,~~983~~906	$	2322,~~297~~983
Research and development credits carryforward		98,~~426~~803		119,~~121~~426
Total gross deferred tax assets		3229,~~409~~709		3432,~~418~~409
Less valuation allowance		(3229,~~392~~709)		(3432,~~059~~392)
Net deferred tax assets	$	17—	$	~~359~~17

ASC 740 requires the reduction of deferred tax assets by a valuation allowance if, based on the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. ~~Because~~The ofCompany ~~the~~is ~~inherent~~projecting ~~uncertainties,~~2026 ~~including~~pre-tax ~~future~~book ~~interest~~loss ~~rates,~~through ~~whether~~the orexpected ~~when~~closing andate ~~acquisition~~ of athe ~~profitable~~pending ~~entity~~Merger ~~will~~with ~~come~~Viskase. toUpon ~~fruition~~review of positive and ~~other~~negative ~~factors~~evidence, ~~projecting~~the ~~long-term~~Company ~~future~~has ~~performance~~concluded ofthat ~~the~~a ~~Company~~full valuation allowance is ~~problematical~~necessary. ~~Accordingly~~Additionally, due to the ~~Company~~valuation isallowance ~~only~~placed ~~projecting~~on ~~2025~~the ~~pre-~~Company’s deferred tax ~~book~~assets, ~~income~~the ~~due~~expiration toof ~~interest~~research ~~rates~~and ondevelopment ~~its~~credits ~~short-term~~and ~~cash~~federal ~~investments~~net ~~and~~operating losses during the ~~absence~~year ofcaused ~~any~~a ~~potentially~~corresponding ~~actionable~~reduction ~~acquisitions~~in atvaluation ~~this~~allowance. ~~time~~As a result, the valuation allowance for the Company decreased during the year ended December 31, 2025.

~~Upon~~Management ~~review~~ of ~~positive and negative evidence in determining a partial reversal of~~ the ~~valuation allowance, the~~ Company ~~increased~~will ~~the~~continue ~~valuation allowance due~~ to ~~decreased~~assess ~~income projections in comparison to~~ the ~~prior~~need ~~year.~~for ~~The~~this ~~Company~~valuation isallowance ~~projecting~~and ~~increased~~will ~~expenses~~make ~~while~~adjustments ~~interest~~when ~~rates may fluctuate slightly throughout 2025~~appropriate. ~~Additionally, due to the valuation allowance placed on~~

At December 31, 2025, the Company had federal net operating loss carryforwards (“NOLs”) of approximately $91.7 million. Approximately $9.2 million of the federal NOLs expired in 2025. Approximately $88.6 million will expire in the years 2026 through 2036. At December 31, 2025, the Company had New Jersey state NOLs of approximately $23.1 million that expire in the years 2031

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ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

~~the~~through ~~Company’s~~2042. ~~deferred~~Under ~~tax~~the ~~assets,~~Tax ~~the~~Cuts ~~expiration~~and ofJobs ~~research~~Act, ~~and~~federal ~~development~~net ~~credits~~operating ~~during~~losses ~~the~~generated ~~year~~in ~~caused~~tax ayears ~~corresponding~~beginning ~~reduction~~after inDecember ~~valuation~~31, ~~allowance.~~2017 Ashave aan ~~result~~unlimited carryforward period, and the ~~valuation~~amount ~~allowance~~of ~~for~~net ~~the~~operating ~~Company~~loss ~~decreased~~allowed ~~during~~to ~~the~~be utilized each year ~~ended~~is ~~December~~limited ~~31,~~to ~~2024~~80% of taxable income.

InThe ~~2024, the~~ Company ~~generated~~also ~~approximately~~had ~~$1.1~~federal ~~million~~research inand ~~taxable~~development ~~income~~(“R&D”) ~~before~~credit ~~utilization~~carryforwards of ~~NOLs.~~approximately ~~The~~$624,000 ~~Company~~that ~~utilized~~expired ~~approximately~~in 2025 and $1.27 million ofthat ~~the~~expired ~~NOLs~~in ~~during 2023~~2024. The Company ~~may~~has ~~acquire~~remaining ~~businesses,~~R&D ~~entities~~credit orcarryforwards ~~revenue~~of ~~streams~~approximately ~~that~~$8.8 ~~could~~million ~~generate sufficient income so~~ that itexpire ~~can~~in ~~utilize~~the ~~its~~years ~~approximately~~2026 ~~$101.4~~through ~~million NOL~~2029. ToThese ~~date,~~deferred notax ~~actionable~~assets ~~acquisition~~were ~~candidates~~subject ~~have~~to ~~been~~a ~~identified~~valuation ~~and,~~allowance ~~while~~such that the ~~Company~~deferred ~~may~~tax ~~ultimately~~expense beincurred ~~successful~~as ina ~~realizing~~result ~~some~~of orthe ~~all~~expiration of the ~~value~~capital ofloss ~~its~~and ~~NOLs,~~R&D ~~the~~credit ~~Company~~carryforwards ~~cannot~~was ~~provide~~offset ~~assurance~~by ~~that~~a itcorresponding ~~will~~deferred betax ~~able~~benefit tofor ~~realize~~the ~~any~~related ~~value~~reduction ofin ~~its~~valuation ~~NOLs~~allowance.

~~Management~~The Company’s ability to use the NOLs and R&D tax credit carryforwards may be limited, as they are subject to certain limitations due to ownership changes as defined by rules pursuant to Section 382 (“Section 382”) of the Code, or may otherwise expire before the Company ~~will~~has ~~continue~~the opportunity to ~~assess~~use them. In an effort to protect stockholder value by attempting to protect against a possible limitation on the ~~need~~Company’s ~~for~~ability ~~this~~to ~~valuation~~use ~~allowance~~its ~~and~~NOLs, ~~will~~the ~~make~~Board ~~adjustments~~adopted ~~when~~a ~~appropriate~~Section 382 rights plan. (See Note 10 to the Consolidated Financial Statements.)

At December 31, 2024, the Company had federal NOLs of approximately $101.4 million, of which approximately $98.3 million will expire in the years 2025 through 2036, and New Jersey state NOLs of approximately $23.7 million that expire in the years 2031 through 2042. Under the Tax Cuts and Jobs Act, federal net operating losses generated in tax years beginning after December 31, 2017 have an unlimited carryforward period, and the amount of net operating loss allowed to be utilized each year is limited to 80% of taxable income.

The Company also had federal research and development (“R&D”) credit carryforwards of approximately $1.7 million that expired in 2024 and $1.6 million that expired in 2023. The Company has remaining R&D credit carryforwards of approximately $9.4 million that expire in the years 2025 through 2029. These deferred tax assets were subject to a valuation allowance such that the deferred tax expense incurred as a result of the expiration of the capital loss and R&D credit carryforwards was offset by a corresponding deferred tax benefit for the related reduction in valuation allowance.

The Company’s ability to use the NOLs and R&D tax credit carryforwards may be limited, as they are subject to certain limitations due to ownership changes as defined by rules pursuant to Section 382 of the Internal Revenue Code of 1986, as amended. However, management of the Company believes that the Company’s NOLs will not be limited by any changes in the Company’s ownership as a result of the successful completion of the Rights Offering. (See Note 13 to the Consolidated Financial Statements.) Additionally, in an effort to protect stockholder value by attempting to protect against a possible limitation on the Company’s ability to use its NOLs, the Board adopted a Section 382 rights plan. (See Note 11 to the Consolidated Financial Statements.)

The Company has not recorded a liability for unrecognized income tax benefits.

On July 4, 2025, the U.S. government enacted the One Big Beautiful Bill Act, which includes several changes to U.S. federal income tax law, including the temporary and permanent extension, of expiring provisions of the Tax Cuts and Jobs Act of 2017. The Company accounted for the tax effects of the legislation, including NOLs and tax credits, in the period of enactment, which is the third quarter of 2025, and concluded that the impact was not material.

(109) Commitments and Contingent Liabilities

~~The~~From ~~Company~~time ~~has~~to ~~been~~time, ~~involved~~we inmay ~~various~~be ~~claims~~engaged ~~and~~in ~~legal~~litigation ~~actions~~ arising in the ordinary course of our business. InWe ~~the~~are ~~opinion~~not ofpresently ~~management,~~a ~~the~~party ~~ultimate~~to ~~disposition~~any oflitigation ~~these~~and ~~matters~~we ~~will~~are not ~~have~~aware aof ~~material~~any ~~effect~~pending onor ~~the~~threatened ~~Company’s~~litigation ~~consolidated~~against ~~financial position, results of operations, or liquidity~~us.

(1110) Section 382 Rights Plan

On August 14, 2020, ~~in an effort to protect stockholder value by attempting to protect against a possible limitation on~~ the Company’s ~~ability~~entered tointo ~~use its NOLs,~~ the ~~Board adopted a~~ Section 382 ~~rights~~Rights ~~plan~~Agreement ~~and~~with ~~declared~~Continental aStock ~~dividend~~Transfer ~~distribution~~& ofTrust ~~one right for each outstanding share of the~~ Company’s, ~~common~~as ~~stock~~rights toagent ~~stockholders~~(as ofamended, ~~record at~~ the ~~close~~“Rights ofAgreement”), ~~business~~in onorder ~~August~~to ~~24,~~protect ~~2020.~~its ~~Accordingly~~NOLs, ~~holders~~certain ofcredits ~~the~~and ~~Company’s~~other ~~common~~tax ~~stock own one preferred stock purchase right for each share of common stock owned by such holder~~attributes. The ~~rights~~Merger ~~are~~Agreement ~~not~~requires ~~immediately~~that ~~exercisable~~the ~~and~~Company ~~will~~terminate ~~become~~the ~~exercisable~~Rights ~~only~~Plan ~~upon~~prior to the ~~occurrence~~consummation of ~~certain events as set forth in~~ the ~~Section~~Merger. ~~382~~On ~~rights~~January ~~plan.~~30, If2026, the ~~rights~~Company ~~become~~entered ~~exercisable,~~into ~~each~~an ~~right~~amendment ~~would~~to ~~initially represent~~ the ~~right~~Rights Agreement to ~~purchase~~extend ~~from~~ the ~~Company~~final ~~one~~expiration ~~one-thousandth~~date of ~~a share of~~ the ~~Company’s~~Rights ~~Series~~Agreement ~~A-1~~to ~~Junior~~February ~~Participating Preferred Stock~~27, ~~par value $0~~2026.01 ~~per~~On ~~share~~February 27, ~~for a purchase price of $1.20 per right. If issued~~2026, ~~each~~the ~~fractional~~Company ~~share~~entered ofinto ~~Series~~an ~~A-1~~additional ~~Junior~~amendment ~~Participating~~to ~~Preferred~~the ~~Stock~~Rights ~~would~~Agreement ~~give~~to ~~the~~extend ~~stockholder approximately~~ the ~~same~~final ~~dividend,~~expiration ~~voting~~date ~~and liquidation rights as does one share~~ of the ~~Company’s~~Rights ~~common~~Agreement ~~stock. However, prior~~ to ~~exercise~~noon, aNew ~~right~~York ~~does~~City ~~not give its holder any rights as a stockholder of the Company~~time, ~~including~~on ~~any~~March ~~dividend~~11, ~~voting or liquidation rights~~2026. The ~~rights~~Company ~~will~~may ~~expire~~further onextend the ~~earliest~~term of ~~(i)~~ the ~~close~~Rights ofAgreement ~~business~~to onthe ~~June~~extent 2,necessary ~~2024~~to ~~(unless~~provide that ~~date is advanced or extended by~~ the ~~Board),~~Rights ~~(ii)~~Agreement ~~the~~will ~~time~~terminate atimmediately ~~which~~prior ~~the~~to ~~rights are redeemed or exchanged under~~ the ~~Section~~date ~~382 rights plan, (iii) the close of business~~ on ~~the day of repeal of Section 382 of the Internal Revenue Code or any successor statute or (iv) the close of business on the first day of a taxable year of the Company to~~ which the ~~Company’s~~Merger ~~Board~~is ~~of Directors determines that no NOLs may be carried forward~~consummated.

(11) Series C Preferred Stock and Rights Offering

On October 9, 2020, the Company completed a rights offering (the “Rights Offering”) pursuant to which it offered its existing stockholders the ability to purchase rights consisting of shares of its Series C Preferred Stock and shares of its Common Stock. In connection with the Rights Offering, the Company realized gross proceeds of approximately $43.6 million and issued 40,000 shares of its Series C Preferred Stock and 30,000,000 shares of its Common Stock. As of December 31, 2025, there are an aggregate of 40,000 shares of Series C Preferred Stock and 74,214,603 shares of Common Stock outstanding.

The terms of the Series C Preferred Stock provide, on an annual basis, that the Board may, at its sole discretion, cause a dividend with respect to the Series C Preferred Stock to be paid in cash to the holders in an amount equal to 3% of the liquidation preference as in effect at such time (initially $1,000 per share). If the dividend is not so paid in cash, the liquidation preference is adjusted and increased annually by an amount equal to 5% of the liquidation preference per share as in effect at such time, that is not paid in cash to the holders on such date. Pursuant to the terms of the Merger Agreement, the Company is not permitted to pay any dividends to the holders of its Common Stock and the Company is not permitted to pay any cash dividends to the holders of its Series C Preferred Stock while the transactions contemplated by the Merger Agreement are pending.

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Table of Contents

ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The initial liquidation value of the Series C Preferred Stock was $1,000 per share. On ~~May~~December 1620, 2024, the ~~Company~~Board ~~entered~~declared ~~into~~a cash dividend of 3% of the ~~Second~~liquidation ~~Amendment~~preference to($42,483,286) of the ~~Section~~Series ~~382~~C ~~Rights~~Preferred ~~Agreement~~Stock, ~~which~~aggregating ~~extends~~approximately ~~the~~$1,275,000 ~~expiration~~($31.86 ~~date~~per share). Such dividend was paid on January 9, 2025 to the ~~close~~holders of ~~business~~record onof ~~March~~the 31Company’s Series C Preferred Stock as of January 2, 2025.

Due to the restrictions in the Merger Agreement, the Company is not permitted to pay a cash dividend on its Series C Preferred Stock for 2025. However, pursuant to the terms of the Series C Preferred Stock, if a cash dividend is not paid, the Company must accrete an increase in liquidation preference equal to 5% of the liquidation preference as in effect at such time. Accordingly, the Series C Preferred Stock was adjusted and increased by an amount equal to 5% of the liquidation preference as in effect at such time ($42,483,400), which aggregated approximately $2,124,000 ($53.10 per share) at December 31, 2025. Following such adjustment the liquidation preference of the Series C Preferred Stock at December 31, 2025 was approximately $44,607,400.

The Company has commenced an exchange offer (the “Series C Exchange Offer”) which allows holders of its Series C Preferred Stock to elect to exchange their shares of Series C Preferred Stock for shares of its Common Stock. Holders of Series C Preferred Stock that do not participate in the Series C Exchange Offer will not have the right to exchange their shares of Series C Preferred Stock into shares of Enzon’s Common Stock following the expiration of the Series C Exchange Offer. The Series C Exchange Offer is open to holders of Enzon’s Series C Preferred Stock that are held by holders other than Icahn Enterprises Holdings L.P., a Delaware limited partnership (“IEH”), and certain of its affiliates (collectively with IEH, the “IEH Parties”). Any shares of Enzon’s Series C Preferred Stock held by holders other than the IEH Parties that are not exchanged for shares of Enzon’s Common Stock in the Series C Exchange Offer will remain outstanding pursuant to their current terms. Pursuant to the terms of the Merger Agreement, the IEH Parties are required to exchange the shares of the Company’s Series C Preferred Stock into shares of the Company’s Common Stock prior to the completion of the Merger in a private exchange offer.

Since November 1, 2022, the Company is able to redeem the Series C Preferred Stock at any time, in whole or in part, for an amount based on the liquidation preference per share as in effect at such time. Accordingly, the Series C Preferred Stock has been classified in mezzanine equity on the Consolidated Balance Sheets. Holders of Series C Preferred Stock have the right to demand that the Company redeem their shares of Series C Preferred Stock in the event that the Company experiences a change of control, such as the Merger. Under the terms of Enzon’s Series C Preferred Stock, Enzon may redeem any outstanding shares of its Series C Preferred Stock for a cash amount equal to the aggregate liquidation preference of such shares.

(12) ~~Rights~~Segment ~~Offering~~Reporting

OnAccounting ~~September~~Standards 1,Codification ~~2020,~~(“ASC”) ~~the Board approved a Rights Offering. For every 1~~280,~~105~~ ~~subscription~~Segment ~~rights held~~Reporting, aestablishes ~~stockholder~~standards ~~was~~for ~~entitled~~reporting tooperating ~~purchase~~segments ~~one~~on ~~Unit~~a atbasis ~~the~~consistent ~~subscription~~with ~~price of $1,090. Each Unit consisted of one share of newly designated Series C Preferred Stock, par value $0.01 per share, and 750 shares of~~ the Company’s ~~common~~internal ~~stock.~~organization Onstructure ~~October~~as 9,well ~~2020, the Rights Offering expired and,~~ as ainformation ~~result~~about ofservices ~~the sale of all 40~~categories,~~000~~ ~~Units,~~business ~~the~~segments ~~Company~~and ~~received~~major ~~approximately~~customers ~~$43.6 million~~ in ~~gross~~financial proceeds and issued shares of Series C Preferred Stock and shares of common stock such that, following the closing of the Rights Offering, there was an aggregate of 40,000 shares of Series C Preferred Stock outstanding and 74,214,603 shares of common stock outstandingstatements.

OnThe anCompany’s ~~annual~~chief ~~basis,~~operating ~~the~~decision ~~Board~~maker may, at its sole discretion, cause a dividend with respect to the Series C Preferred Stock to be paid in cash to the holders in an amount equal to 3% of the liquidation preference as in effect at such time (~~initially $1,000 per share~~“CODM”). ~~If the dividend~~ is ~~not~~its sochief ~~paid~~executive ~~in cash~~officer, ~~the~~who ~~liquidation preference~~ is ~~adjusted~~also ~~and~~its ~~increased~~chief ~~annually~~financial ~~by an amount equal to 5% of the liquidation preference per share as in effect at such time, that is not paid in cash to the holders on such date~~officer. ~~Holders~~As ~~of Series C Preferred Stock do not have any voting rights and~~ the ~~Series~~Company ~~C Preferred Stock~~ is ~~not~~a ~~convertible~~public ~~into~~company ~~shares~~acquisition ~~of the Company’s common stock. The initial liquidation value of the Series C Preferred Stock was $1~~vehicle,~~000~~ ~~per~~where ~~share.~~it Atcan ~~December~~become ~~31,~~an ~~2021~~acquisition ~~the liquidation value of the Series C Preferred Stock was $1~~platform,~~062~~ ~~per~~has ~~share, inasmuch as~~ no ~~dividend~~operating ~~was~~activities ~~declared~~and orderives ~~paid in cash. On December 29, 2022,~~ the ~~Board~~majority ~~declared a cash dividend~~ of 3%its onincome ~~the~~from ~~Series C Preferred Stock~~interest, ~~aggregating~~our ~~approximately~~CODM ~~$1,275,000~~evaluates orperformance ~~$31.86~~and ~~per~~makes ~~share.~~operating ~~Accordingly,~~decisions ~~the~~about ~~liquidation~~allocating ~~value~~resources ofbased ~~the~~on ~~Series~~financial Cdata ~~Preferred~~presented ~~Stock was $1,062 per share~~ on ~~December~~a ~~31,~~consolidated ~~2022~~basis. ~~The~~As ~~dividend was paid on January 17~~such, ~~2023 to~~ the ~~holders of record of the~~ Company’s ~~Series~~operates ~~C Preferred Stock~~ as ofone ~~January~~reportable ~~10, 2023~~segment. On December 28, 2023, the Board declared a cash dividend of 3% on the Series C Preferred Stock, aggregating approximately $1,275,000 or $31.86 per share. Accordingly, the liquidation value of the Series C Preferred Stock remained at $1,062 per share on December 31, 2023. The ~~dividend~~CODM ~~was~~uses ~~paid~~consolidated onnet ~~January~~(loss) ~~17,~~income ~~2024~~ to ~~the~~assess ~~holders~~financial ofperformance ~~record~~and ofallocate ~~the Company’s Series C Preferred Stock as of January 10, 2024~~resources. On December 20, 2024, the Board declared a cash dividend of 3% on the Series C Preferred Stock, aggregating approximately $1,275,000 or $31.86 per share. Accordingly, the liquidation value of the Series C Preferred Stock remained at $1,062 per share on December 31, 2024. The ~~dividend~~significant ~~was~~expenses ~~paid~~within onnet ~~January~~(loss) 9,income ~~2025~~are toseparately ~~the~~presented ~~holders~~in ~~of record of~~ the Company’s ~~Series~~Consolidated CStatements ~~Preferred Stock as~~ of ~~January 2, 2025~~Operations.

As of November 1, 2022, the Company is able to redeem the Series C Preferred Stock at any time, in whole or in part, for an amount based on the liquidation preference per share as in effect at such time. Holders of Series C Preferred Stock have the right to demand that the Company redeem their shares in the event that the Company undergoes a change of control as defined in the Certificate of Designation of the Series C Preferred Stock.

(13) ~~Series~~Merger ~~C Preferred Stock~~Agreement

InOn ~~October~~June ~~2020~~20, 2025, the Company, ~~issued~~Merger 40Sub and Viskase entered into the Merger Agreement. Upon the terms and subject to the satisfaction or waiver of the conditions described in the Merger Agreement,~~000~~ ~~shares~~at the effective time of the merger, Merger Sub will be merged with and into Viskase, with Viskase as the surviving entity following the Merger. Following consummation of the Merger, it is anticipated that Enzon’s pre-closing stockholders, including holders of the Series C Preferred Stock who exchange their shares for anshares ~~aggregate~~of ~~purchase~~Enzon’s ~~price~~Common Stock pursuant to the Series C Exchange Offer, will hold 45% of ~~$40~~the outstanding shares of Enzon’s Common Stock and Viskase’s pre-closing stockholders will hold 55% of the outstanding shares of Enzon’s Common Stock.0 ~~million~~If the Merger is completed, Enzon Pharmaceuticals, Inc. will change its name to “Viskase Holdings, Inc.” and its common stock will be quoted on the OTCQB tier of the OTC Markets Group, Inc., although pursuant to the rules of the OTCQB, Enzon is required to re-apply to the OTCQB following such change of control transaction.

There is no prohibition on the repurchase or redemption of Series C Preferred Shares while there is any arrearage in the payment of dividends.

Since the redemption of the Series C Preferred Stock is contingently or optionally redeemable, unless and until we undertake a change of control the Series C Preferred Stock has been classified in mezzanine equity on the Consolidated Balance Sheets.

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Table of Contents

ENZON PHARMACEUTICALS, INC. AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The Merger Agreement and the transactions contemplated thereby, including the anticipated amendment to the Company’s Amended and Restated Certificate of Incorporation to effect the consolidation of the issued and outstanding shares of the Enzon’s Common Stock at a ratio of 1-for-100 (14which the Company refers to as the “Reverse Stock Split”) ~~Segment~~, ~~Reporting~~were approved by the requisite holders of Enzon’s Common Stock. The closing of the transactions contemplated by the Merger Agreement is subject to satisfaction or waiver of the remaining customary conditions to closing as set forth in the Merger Agreement.

~~Accounting Standards Codification~~ (~~“ASC”~~14) Common ~~280,~~Stock Segment Reporting, establishes standards for reporting operating segments on a basis consistent with the Company’s internal organization structure as well as information about services categories, business segments and ~~major~~Trading ~~customers in financial statements.~~ Market

~~The~~On ~~Company’s~~August ~~chief~~11, ~~operating decision maker (“CODM”) is its chief executive officer~~2025, ~~who is also its chief financial officer. As~~ the Company iswas anotified ~~public~~by ~~company~~the ~~acquisition~~OTCQX ~~vehicle,~~Markets ~~where~~Group it(the ~~can become an acquisition platform~~“OTCQX”), ~~has~~the nomarketplace ~~operating~~for ~~activities~~the ~~and derives~~ over-the-counter ~~majority~~trading of its ~~income from interest~~stock, ~~our~~that ~~CODM~~it ~~evaluates~~no ~~performance~~longer ~~and~~met ~~makes~~the ~~operating~~standards ~~decisions~~for ~~about~~continued ~~allocating~~qualification ~~resources~~for ~~based~~the onOTCQX, ~~financial~~in ~~data~~that ~~presented~~its onstock abid ~~consolidated~~price ~~basis.~~had Asfallen ~~such,~~below ~~the Company operates as one reportable segment~~$0.10 ~~The~~per ~~CODM~~share ~~uses~~for ~~consolidated~~30 ~~net~~consecutive ~~income~~calendar ~~to assess financial performance and allocate resources~~days. ~~The~~On ~~significant~~August ~~expenses~~12, ~~within~~2025, ~~net~~the ~~income~~Company ~~are~~began ~~separately~~trading ~~presented~~ on the ~~Company’s~~OTCQB ~~Consolidated Statements of Operations~~Market.

(15) Subsequent ~~Event~~Events

On ~~December~~January 1930, ~~2024~~2026, aas ~~member~~required ofby the ~~special~~Merger ~~committee~~Agreement of(see ~~the~~Note ~~Board~~13), ofthe ~~Directors~~Company ofcommenced ~~Viskase~~an ~~Companies,~~exchange ~~Inc.~~offer ~~(“Viskase”)~~pursuant ~~contacted~~to ~~the~~which ~~Chairman of~~ the ~~Board~~Company tooffered ~~explore~~each ~~interest~~holder inof athe ~~potential~~its ~~business~~Series ~~combination~~C ~~transaction~~Preferred ~~involving~~Stock ~~Viskase~~to ~~and~~exchange ~~the~~each ~~Company~~share ~~through~~of aEnzon’s ~~negotiated~~Series ~~merger~~C ~~transaction~~Preferred orStock ~~otherwise~~held (aby ~~“Potential~~such ~~Transaction”)~~stockholder ~~and~~for toa ~~indicate~~number ~~that~~of ~~Viskase~~shares ~~may~~of ~~formulate~~Enzon’s ~~and~~Common ~~submit~~Stock aequal ~~proposal~~to ~~with~~(i) ~~respect~~the toaggregate aliquidation ~~potential~~preference ~~structure~~of ~~and~~each ~~terms~~share ~~for~~of aEnzon’s ~~Potential~~Series ~~Transaction.~~C ~~The~~Preferred ~~Viskase~~Stock, ~~special~~divided ~~committee~~by ~~member~~(ii) ~~further~~$7.83 ~~indicated~~after ~~that~~giving iteffect isto the ~~expectation~~Reverse ofStock ~~Viskase’s~~Split ~~special~~(referred ~~committee~~to ~~that~~as athe ~~special~~“Series ~~committee~~C ofExchange ~~independent~~Offer”). ~~directors~~The ofSeries ~~the~~C ~~Company~~Exchange Offer will beexpire ~~established~~one tominute ~~consider~~after ~~Viskase’s~~11:59 ~~proposal~~p.m., ~~and~~Eastern ~~such~~Time, ~~other~~on ~~terms~~March of9, ~~the~~2026, ~~Potential~~unless ~~Transaction~~extended asor ~~may~~terminated bein ~~considered~~Enzon’s ~~and~~sole ~~negotiated~~discretion or in ~~the~~accordance ~~future.~~with applicable law.

On ~~January~~February 711, ~~2025~~2026, inthe ~~addition~~Company toreceived the ~~appointment~~requisite ofconsents afrom ~~new~~holders ~~director,~~of ~~Stephen~~its T.Common ~~Wills,~~Stock approving the ~~Board~~Merger ~~formed~~Agreement aand ~~special~~the ~~committee~~transactions ofcontemplated ~~independent~~thereby, ~~directors~~including (the ~~“Special~~anticipated ~~Committee”)~~amendment ~~and~~to ~~delegated~~the ~~full~~Company’s ~~authority~~Amended toand ~~the~~Restated ~~Special~~Certificate ~~Committee~~of Incorporation to ~~consider,~~effect ~~negotiate~~the ~~and~~consolidation ~~vote~~of ~~upon~~the ~~any~~issued ~~Potential~~and ~~Transaction~~outstanding ~~proposed,~~shares asof ~~well~~the asEnzon’s ~~any~~Common ~~strategic~~Stock ~~alternatives~~at ~~that~~a ~~may~~ratio beof ~~put~~1-for-100 ~~forth~~(which ~~with~~we ~~regard~~refer to as the ~~Potential~~“Reverse ~~Transaction~~Stock Split”). The ~~Special~~Reverse ~~Committee~~Stock isSplit ~~comprised~~has ofnot ~~Randolph~~yet ~~Read~~been ~~and~~effected ~~Stephen~~but T.will ~~Wills.~~be ~~The~~effective ~~Special~~prior ~~Committee~~to ~~continues~~the tocompletion ~~consider~~of the ~~Potential~~Merger. ~~Transaction~~The ~~and~~closing noof ~~assurances~~the ~~can~~transactions becontemplated ~~given~~by ~~that~~the aMerger ~~definitive~~Agreement ~~agreement~~is ~~will~~subject beto ~~reached~~satisfaction or ~~that~~waiver aof ~~Potential~~the ~~Transaction~~remaining ~~will~~conditions beto ~~consummated~~closing as set forth in the Merger Agreement.

On January 30, 2026, the Company entered into an amendment to the Rights Agreement (see Note 10) to extend the final expiration date of the Rights Agreement to February 27, 2026. On February 27, 2026, the Company entered into an additional amendment to the Rights Agreement to extend the final expiration date of the Rights Agreement to noon, New York City time, on March 11, 2026. The Merger Agreement requires that we terminate the Rights Plan prior to the consummation of the Merger. We may further extend the term of the Rights Agreement to the extent necessary to provide that the Rights Agreement will terminate immediately prior to the date on which the Merger is consummated.

F-15

December 31,

December 31,

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