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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-Q

(Mark One)

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

For the quarterly period ended September 30, 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: 001-41740

Apogee Therapeutics, Inc.

(Exact name of registrant as specified in its charter)



Delaware	93-4958665
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification Number)

221 Crescent St., Building 17, Suite 102b

Waltham, MA 02453

(650) 394‑5230

(Address including zip code, and telephone number including area code, of registrant’s principal executive offices)

Former name, former address and former fiscal year, if changed since last report: N/A

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


Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, par value $0.00001 per share	APGE	The Nasdaq Global Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities 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 is a shell company (as defined in Rule 12b‑2 of the Exchange Act). Yes ☐ No ☒

As of November 3, 2025, the registrant had 68,320,229 shares of common stock, $0.00001 par value per share, outstanding, comprising 54,833,587 shares of voting common stock, $0.00001 par value per share, and 13,486,642 shares of non-voting common stock, $0.00001 par value per share.

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APOGEE THERAPEUTICS, INC.

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		Page
PART I	FINANCIAL INFORMATION	1
Item 1.	Condensed Consolidated Financial Statements (Unaudited)	1
	Condensed Consolidated Balance Sheets as of September 30, 2025 and December 31, 2024	1
	Condensed Consolidated Statement of Operations for the Three and Nine Months Ended September 30, 2025 and 2024	2
	Condensed Consolidated Statement of Comprehensive Loss for the Three and Nine Months Ended September 30, 2025 and 2024	3
	Condensed Consolidated Statement of Stockholders’ Equity for the Three and Nine Months Ended September 30, 2025 and 2024	4
	Condensed Consolidated Statement of Cash Flows for the Nine Months Ended September 30, 2025 and 2024	6
	Notes to the Unaudited Interim Condensed Consolidated Financial Statements	7
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	25
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	43
Item 4.	Controls and Procedures	43
PART II	OTHER INFORMATION	44
Item 1.	Legal Proceedings	44
Item 1A.	Risk Factors	44
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	76
Item 3.	Defaults Upon Senior Securities	76
Item 4.	Mine Safety Disclosures	76
Item 5.	Other Information	76
Item 6.	Exhibits	77
	Signatures	78

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q (this “Quarterly Report”) contains “forward-looking statements” within the meaning of the federal securities laws, which statements are subject to substantial risks and uncertainties and are based on current expectations, estimates, forecasts and assumptions. All statements other than statements of historical fact included in this Quarterly Report, including statements concerning our plans, objectives, goals, strategies, future events, future revenues or performance, capital requirements or financing needs, capital expenditures, commitments, preclinical studies, clinical trials, plans or intentions relating to product candidates, expected markets, business trends and other statements, including without limitation, those discussed under the sections titled “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations”, are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “may,” “might,” “will,” “would,” “shall,” “intend,” “target,” “should,” “could,” “can,” “expect,” “anticipate,” “believe,” “design,” “estimate,” “forecast,” “predict,” “potential,” “plan,” “seek,” or “continue” or the negative of these terms and similar expressions intended to identify forward-looking statements. Forward-looking statements reflect our current views with respect to future events. Given the significant risks and uncertainties, you should not place undue reliance on these forward-looking statements.

There are a number of risks, uncertainties and other factors that could cause our actual results to differ materially from the forward-looking statements expressed or implied in this Quarterly Report. Such risks, uncertainties and other factors include, among others, the following:

•

our plans to develop and commercialize our product candidates for the treatment of atopic dermatitis, asthma, eosinophilic esophagitis, chronic obstructive pulmonary disease, and related inflammatory and immunology indications with high unmet need;

•

our ability to obtain funding for our operations, including funding necessary to complete the development and commercialization of our product candidates;

•

the timing and focus of our ongoing and future preclinical studies and clinical trials and the reporting of data from those studies and trials;

•

the beneficial characteristics, safety, efficacy and therapeutic effects of our programs;

•

our plans relating to the further development of our programs, including additional indications we may pursue;

•

the size of the market opportunity for our programs, including our estimates of the number of patients who suffer from the diseases we are targeting;

•

our continued reliance on third parties to conduct additional preclinical studies and clinical trials of our programs and for the manufacture of our product candidates for preclinical studies and clinical trials;

•

the success, cost and timing of our preclinical and clinical development activities and planned clinical trials;

•

our plans regarding, and our ability to obtain, and negotiate favorable terms of, any collaboration, licensing or other arrangements that may be necessary or desirable to develop, manufacture or commercialize our product candidates;

•

the timing of and our ability to obtain and maintain regulatory approvals for our programs, as well as potential future programs;

•

the rate and degree of market acceptance and clinical utility of our programs;

•

the success of competing treatments that are or may become available;

•

our ability to attract and retain key management and technical personnel;

•

our expectations regarding our ability to obtain, maintain and enforce intellectual property protection for our programs;

•

our financial performance;

•

the period over which we estimate our existing cash and cash equivalents, marketable securities and long-term marketable securities will be sufficient to fund our future operating expenses and capital expenditure requirements;

•

our anticipated use of our existing resources;

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•

adverse macroeconomic conditions, including inflation, slower growth or recession, new or increased tariffs and other barriers to trade, changes to fiscal and monetary policy or government budget dynamics (particularly in the pharmaceutical and biotech areas), volatility in financial markets and other challenges in the global economy; and

•

uncertainty around the funding, functioning and policy priorities of the U.S. federal regulatory agencies, including the U.S. Food and Drug Administration.

These and other risks and uncertainties and other factors, including those discussed under the section titled “Risk Factors” of this Quarterly Report, may cause our actual results and outcomes, or timing of our results or outcomes, to differ materially and adversely from the forward-looking statements expressed or implied in this Quarterly Report including factors disclosed in the sections titled “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations.” You should evaluate all forward-looking statements made in this Quarterly Report in the context of these risks and uncertainties.

We caution you that the risks, uncertainties and other factors referred to above and elsewhere in this Quarterly Report may not contain all of the risks, uncertainties and other factors that may affect us, our future results or our operations. Moreover, new risks may emerge from time to time. It is not possible for us to predict all risks. In addition, we cannot assure you that we will realize the results, benefits or developments that we expect or anticipate or, even if substantially realized, that they will result in the consequences or affect us or our business in the way expected.

All forward-looking statements in this Quarterly Report apply only as of the date made and are expressly qualified in their entirety by this and other cautionary statements included in this Quarterly Report. Except as required by law, we undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, subsequent events, changes in assumptions or circumstances or otherwise.

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

The Apogee name and logo are our registered trademarks. This Quarterly Report contains references to our trademarks and to trademarks and service marks belonging to other entities. Solely for convenience, trademarks, service marks and trade names referred to in this Quarterly Report, including logos, artwork and other visual displays, may appear without the ®, SM, or ™ symbols, but such references are not intended to indicate in any way that we will not assert, to the fullest extent under applicable law, our rights or the rights of the applicable licensor to these trademarks and trade names. We do not intend our use or display of other entities’ trade names, trademarks or service marks to imply a relationship with, or endorsement or sponsorship of us by, any other entity.

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PART I – FINANCIAL INFORMATION

APOGEE THERAPEUTICS, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

(UNAUDITED)

(In thousands, except share data)


	SEPTEMBER 30, 2025			DECEMBER 31, 2024
Assets
Current assets:
Cash and cash equivalents	$	107,914		$	141,789
Marketable securities		419,375			378,864
Prepaid expenses and other current assets		12,808			9,060
Total current assets		540,097			529,713
Long-term marketable securities		61,640			210,416
Property and equipment, net		6,032			1,959
Right-of-use asset, net		9,646			11,365
Other non-current assets		8,744			498
Total assets	$	626,159		$	753,951
Liabilities and stockholders' equity
Current liabilities:
Accounts payable	$	376		$	1,071
Lease liability		4,079			3,234
Accrued expenses and other current liabilities		29,592			24,255
Total current liabilities		34,047			28,560
Long-term liabilities:
Lease liability, net of current		5,774			8,597
Total liabilities		39,821			37,157
Commitments and contingencies (Note 9)
Stockholders' equity:
Common Stock; $0.00001 par value, 400,000,000 authorized, 60,147,727 issued and 59,315,738 outstanding as of September 30, 2025; 400,000,000 authorized, 59,478,725 issued and 58,062,898 outstanding as of December 31, 2024		1			1
Additional paid-in capital		1,077,681			1,021,794
Accumulated other comprehensive income		1,028			915
Accumulated deficit		(492,372	)		(305,916	)
Total stockholders’ equity		586,338			716,794
Total liabilities and stockholders’ equity	$	626,159		$	753,951

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

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APOGEE THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS

(UNAUDITED)

(In thousands, except share and per share data)


	THREE MONTHS ENDED SEPTEMBER 30,						NINE MONTHS ENDED SEPTEMBER 30,
	2025			2024			2025			2024
Operating expenses:
Research and development (1)	$	54,178		$	45,714		$	156,268		$	107,636
General and administrative		17,100			12,972			51,271			33,353
Total operating expenses		71,278			58,686			207,539			140,989
Loss from operations		(71,278	)		(58,686	)		(207,539	)		(140,989	)
Other income, net:
Interest income, net		6,318			9,668			21,299			26,061
Total other income, net		6,318			9,668			21,299			26,061
Net loss before taxes		(64,960	)		(49,018	)		(186,240	)		(114,928	)
Provision for income taxes		(61	)		—			(216	)		—
Net loss after taxes	$	(65,021	)	$	(49,018	)	$	(186,456	)	$	(114,928	)
Net loss per share, basic and diluted	$	(1.11	)	$	(0.86	)	$	(3.19	)	$	(2.11	)
Weighted-average common shares outstanding, basic and diluted		58,773,731			56,795,544			58,467,901			54,508,496

(1)

Includes no related party amounts for the three months ended September 30, 2025 and $130 for the nine months ended September 30, 2025. Includes related party amounts of $2,447 and $11,125 for the three and nine months ended September 30, 2024, respectively.

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

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APOGEE THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE LOSS

(UNAUDITED)

(In thousands)


	THREE MONTHS ENDED SEPTEMBER 30,						NINE MONTHS ENDED SEPTEMBER 30,
	2025			2024			2025			2024
Net loss	$	(65,021	)	$	(49,018	)	$	(186,456	)	$	(114,928	)
Unrealized gain on marketable securities, net of tax		343			3,559			113			2,941
Comprehensive loss	$	(64,678	)	$	(45,459	)	$	(186,343	)	$	(111,987	)

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

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APOGEE THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS’ EQUITY

(UNAUDITED)

(In thousands, except share data)


	COMMON STOCK				ADDITIONAL PAID-IN CAPITAL		ACCUMULATED DEFICIT			ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)			TOTAL STOCKHOLDERS' EQUITY
	SHARES		AMOUNT		AMOUNT		AMOUNT			AMOUNT			AMOUNT
Balance at December 31, 2024		58,062,898	$	1	$	1,021,794	$	(305,916	)	$	915		$	716,794
Vesting of restricted stock		213,104		—		—		—			—			—
Issuance of common stock upon exercise of stock options		28,799		—		622		—			—			622
Equity-based compensation expense		—		—		11,126		—			—			11,126
Unrealized gain on marketable securities, net of tax		—		—		—		—			159			159
Net loss		—		—		—		(55,339	)		—			(55,339	)
Balance at March 31, 2025		58,304,801	$	1	$	1,033,542	$	(361,255	)	$	1,074		$	673,362
Vesting of restricted stock		213,031		—		—		—			—			—
Issuance of common stock upon exercise of stock options		21,123		—		384		—			—			384
Issuance of common stock under employee stock purchase plan		21,570		—		796		—			—			796
Equity-based compensation expense		—		—		11,344		—			—			11,344
Unrealized loss on marketable securities, net of tax		—		—		—		—			(389	)		(389	)
Net loss		—		—		—		(66,096	)		—			(66,096	)
Balance at June 30, 2025		58,560,525	$	1	$	1,046,066	$	(427,351	)	$	685		$	619,401
Vesting of restricted stock		212,026		—		—		—			—			—
Common stock issued, net of issuance costs of $618, under at the market equity offering program ("ATM")		527,437				19,382		—			—			19,382
Issuance of common stock upon exercise of stock options		15,750		—		356		—			—			356
Equity-based compensation expense		—		—		11,877		—			—			11,877
Unrealized gain on marketable securities, net of tax		—		—		—		—			343			343
Net loss		—		—		—		(65,021	)		—			(65,021	)
Balance at September 30, 2025		59,315,738	$	1	$	1,077,681	$	(492,372	)	$	1,028		$	586,338

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

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APOGEE THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS’ EQUITY

(UNAUDITED)

(In thousands, except share data)


	COMMON STOCK				ADDITIONAL PAID-IN CAPITAL		ACCUMULATED DEFICIT			ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)			TOTAL STOCKHOLDERS' EQUITY
	SHARES		AMOUNT		AMOUNT		AMOUNT			AMOUNT			AMOUNT
Balance at December 31, 2023		48,338,769	$	—	$	503,354	$	(123,770	)	$	329		$	379,913
Common stock issued, net of issuance costs of $33,045		7,790,321		1		449,954		—			—			449,955
Vesting of restricted stock		237,665		—		—		—			—			—
Issuance of common stock upon exercise of stock options		1,047		—		24		—			—			24
Equity-based compensation expense		—		—		4,186		—			—			4,186
Unrealized loss on marketable securities, net of tax		—		—		—		—			(506	)		(506	)
Net loss		—		—		—		(32,094	)		—			(32,094	)
Balance at March 31, 2024		56,367,802	$	1	$	957,518	$	(155,864	)	$	(177	)	$	801,478
Vesting of restricted stock		292,477		—		—		—			—			—
Issuance of common stock upon exercise of stock options		628		—		14		—			—			14
Issuance of common stock under employee stock purchase plan		15,558		—		377		—			—			377
Equity-based compensation expense		—		—		5,698		—			—			5,698
Unrealized loss on marketable securities, net of tax		—		—		—		—			(112	)		(112	)
Net loss		—		—		—		(33,816	)		—			(33,816	)
Balance at June 30, 2024		56,676,465	$	1	$	963,607	$	(189,680	)	$	(289	)	$	773,639
Vesting of restricted stock		203,465		—		—		—			—			—
Issuance of common stock upon exercise of stock options		19,365		—		383		—			—			383
Equity-based compensation expense		—		—		5,839		—			—			5,839
Unrealized gain on marketable securities, net of tax		—		—		—		—			3,559			3,559
Net loss		—		—		—		(49,018	)		—			(49,018	)
Balance at September 30, 2024		56,899,295	$	1	$	969,829	$	(238,698	)	$	3,270		$	734,402

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

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APOGEE THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS

(UNAUDITED)

(In thousands)


	NINE MONTHS ENDED SEPTEMBER 30,
	2025			2024
Cash flows from operating activities:
Net loss	$	(186,456	)	$	(114,928	)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation expense		1,012			113
Equity-based compensation expense		34,347			15,723
Amortization of discounts on marketable securities		(5,759	)		(9,255	)
Non-cash lease expense		2,718			933
Changes in operating assets and liabilities:
Prepaid expenses and other current assets		(3,748	)		(5,484	)
Other non-current assets		(8,540	)		(113	)
Accounts payable		(695	)		73
Operating lease liability		(2,977	)		(736	)
Accrued expenses		5,337			10,214
Net cash used in operating activities		(164,761	)		(103,460	)
Cash flows from investing activities:
Purchases of marketable securities		(253,212	)		(588,866	)
Maturities of marketable securities		367,349			243,190
Purchases of property and equipment		(5,085	)		(1,153	)
Net cash provided by (used in) investing activities		109,052			(346,829	)
Cash flows from financing activities:
Proceeds from issuance of common stock, net of issuance costs		—			449,955
Proceeds from issuance of common stock under the ATM, net of issuance costs		19,382			—
Proceeds from exercise of options and employee stock purchase plan purchases		2,158			798
Net cash provided by financing activities		21,540			450,753
(Decrease) increase in cash, cash equivalents and restricted cash		(34,169	)		464
Cash, cash equivalents and restricted cash, beginning of period		142,083			118,610
Cash, cash equivalents and restricted cash, end of period	$	107,914		$	119,074
Supplemental disclosures of non-cash activities:
Operating lease right-of-use asset obtained in exchange for operating lease liability	$	999		$	10,842
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	$	107,914		$	118,780
Restricted cash		—			294
Total	$	107,914		$	119,074

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

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APOGEE THERAPEUTICS, INC.

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(UNAUDITED)

Nature of the Business

Apogee Therapeutics, Inc., together with its consolidated subsidiary (collectively, “Apogee” or the “Company”), is a clinical-stage biotechnology company advancing optimized, novel biologics with the potential for differentiated efficacy and dosing in the largest inflammatory and immunology (“I&I”) markets, including for the treatment of atopic dermatitis (“AD”), asthma, eosinophilic esophagitis (“EoE”), chronic obstructive pulmonary disease (“COPD”), and other I&I indications. Apogee’s antibody programs are designed to overcome limitations of existing therapies by targeting well-established mechanisms of action and incorporating advanced antibody engineering to optimize half-life and other properties.

The Company commenced its operations in February 2022 as a Delaware limited liability company named Apogee Therapeutics, LLC. The Company was founded by leading healthcare investors, Fairmount Funds Management LLC and Venrock Healthcare Capital Partners and has since assembled a management team of drug developers and an executive team with significant experience in clinical development, manufacturing of biologics and leading public biopharmaceutical company operations, financings and transactions. As a result of the Company’s reorganization from a limited liability company to a corporation in July 2023 (the “Reorganization”) and in connection with the Company’s initial public offering (“IPO”) in July 2023, the Company directly wholly owns the assets of Apogee Therapeutics, LLC, including the stock of its subsidiary. In addition, the Company engages third parties, including Paragon Therapeutics, Inc. (“Paragon”), who is also a related party, to perform ongoing research and development and other services on its behalf.

In February 2022, the Company entered into an antibody discovery and option agreement with Paragon, which was subsequently amended in November 2022 (as amended, the “2022 Option Agreement”). Under the terms of the 2022 Option Agreement, Paragon identifies, evaluates and develops antibodies directed against certain mutually agreed therapeutic targets of interest to the Company. The 2022 Option Agreement initially included two selected targets, IL-13 and IL-4Rα, and was subsequently amended in November 2022 to include an additional selected target, OX40L. Under the 2022 Option Agreement, the Company has the exclusive option to, on a research program-by-research program basis, be granted an exclusive, worldwide license to all of Paragon’s right, title and interest in and to the intellectual property resulting from the applicable research program to develop, manufacture and commercialize the antibodies and products directed to the selected targets. In November 2023, the Company entered into an additional antibody discovery and option agreement for the thymic stromal lymphopoietin (“TSLP”) target with Paragon (the “2023 Option Agreement” and, together with the 2022 Option Agreement, collectively the “Option Agreements”). Under the terms of the 2023 Option Agreement, Paragon identifies, evaluates and develops antibodies directed against certain mutually agreed therapeutic targets of interest to the Company.

In November 2022, the Company exercised its option available under the 2022 Option Agreement with respect to the IL-13 Research Program (as defined below) and, in April 2023, the Company exercised its options available under the 2022 Option Agreement with respect to the IL-4Rα Research Program and the OX40L Research Program. Upon such exercises, the parties entered into associated license agreements for each target. Under the terms of each license agreement, Paragon granted to the Company an exclusive, worldwide, royalty-bearing, sublicensable right and license with respect to certain information, patent rights and sequence information related to antibodies directed at the respective target to use, make, sell, import, export and otherwise exploit the antibodies directed at the respective target. In August 2024, the Company exercised its option under the 2023 Option Agreement with respect to the TSLP Research Program. The Company is solely responsible for the development, manufacture and commercialization of IL-13, IL-4Rα, OX40L and TSLP product candidates and products at its own cost and expense.

In July 2023, the Company completed its IPO, pursuant to which it issued and sold an aggregate of 20,297,500 shares of its common stock (inclusive of 2,647,500 shares pursuant to the exercise of the underwriters’ overallotment option in full) at the IPO price of $17.00 per share for net cash proceeds of $315.4 million, after deducting underwriting discounts and commissions and other offering expenses. The shares of Apogee Therapeutics, Inc. began trading on the Nasdaq Global Market on July 14, 2023, under the symbol APGE. On March 12, 2024, the Company issued and sold an aggregate of 7,790,321 shares of its common stock (inclusive of 1,016,128 shares pursuant to the exercise in full of the underwriters’ option to purchase additional shares) at a public offering price of $62.00 per share, for aggregate net proceeds of $450.0 million after deducting underwriting discounts and commissions and other offering expenses. On October 10, 2025, the Company announced the closing of an underwritten public offering. The Company issued and sold 8,048,782 shares of its common stock, including the full exercise of the underwriters’ option to purchase 1,097,561 additional shares, at a public offering price of $41.00 per share and, in lieu of common stock to certain investors, pre-funded warrants to purchase up to 365,853 shares of common stock at a price of $40.99999 per warrant (the “October 2025 Offering”). The pre-funded warrants have an exercise price of $0.00001 per share and are exercisable immediately. The net proceeds from the October 2025 Offering, including proceeds

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from the exercise in full of the underwriters’ option to purchase additional shares, were approximately $324.1 million, after deducting underwriting discounts and commissions and other offering expenses.

The Company is subject to risks and uncertainties common to early stage companies in the biotechnology industry, including, but not limited to, completing preclinical studies and clinical trials, obtaining regulatory approval for its programs, market acceptance of products, development by competitors of new technological innovations, dependence on key personnel, the ability to attract and retain qualified employees, reliance on third-party organizations, protection of proprietary technology, compliance with government regulations, and the ability to raise additional capital to fund operations. The Company’s programs currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure, and extensive compliance reporting capabilities. Even if the Company’s development efforts are successful, it is uncertain when, if ever, the Company will realize revenue from product sales. The Company has primarily funded its operations with proceeds from the sales of preferred units and common stock and has not generated any revenue since inception.

As a result, the Company will need substantial additional funding to support its continued operations and growth strategy. Until such a time as the Company can generate significant revenue from product sales, if ever, the Company expects to finance its operations through the sale of equity, debt financings or other capital sources, including collaborations with other companies or other strategic transactions. The Company may be unable to raise additional funds or enter into such other agreements on favorable terms, or at all. If the Company fails to raise capital or enter into such agreements as, and when, needed, the Company may have to significantly delay, scale back or discontinue the development and commercialization of one or more of its product candidates.

Company Liquidity

The Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year after the date that the accompanying consolidated financial statements are issued. The Company had an accumulated deficit of $492.4 million as of September 30, 2025. Further, the Company incurred a net loss of $186.5 million and experienced negative cash flows from operations of $164.8 million for the nine months ended September 30, 2025. Based on the Company’s current operating plan, it estimates that its cash and cash equivalents of $107.9 million, marketable securities of $419.4 million and long-term marketable securities of $61.6 million as of September 30, 2025, will be sufficient to enable the Company to fund its operating expenses and capital requirements through at least the next 12 months from the issuance of these consolidated financial statements.

The Company is subject to those risks associated with any biotechnology company that has substantial expenditures for research and development. There can be no assurance that the Company’s research and development projects will be successful, that products developed will obtain necessary regulatory approval, or that any approved product will be commercially viable. In addition, the Company operates in an environment of rapid technological change and is largely dependent on the services of its employees and consultants. If the Company fails to become profitable or is unable to sustain profitability on a continuing basis, then it may be unable to continue its operations at planned levels and be forced to reduce its operations.

This Quarterly Report contains references to the Company’s programs, which are used interchangeably to refer to the Company’s clinical programs within its pipeline and its products under development.

Summary of Significant Accounting Policies

There have been no material changes to the significant accounting policies as disclosed in Note 2 to the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024.

Basis of Presentation

The condensed consolidated financial statements include the accounts of Apogee Therapeutics, Inc. and its wholly-owned subsidiaries, Apogee Therapeutics Securities Corporation, formed as a Massachusetts security corporation in September 2024, and Apogee Biologics, Inc. until December 31, 2024, when Apogee Biologics, Inc. merged with and into Apogee Therapeutics, Inc. with Apogee Therapeutics, Inc. surviving the merger.

These condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates of the Financial

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Accounting Standards Board (“FASB”). In the Company’s management opinion, the information furnished in these unaudited condensed consolidated financial statements reflect all adjustments, all of which are of a normal and recurring nature, necessary for a fair presentation of the financial position and results of operations for the interim reported periods. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year or any other interim period.

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Apogee Therapeutics, Inc. and its wholly-owned subsidiary. All intercompany balances and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts in the financial statements and accompanying notes. Actual results could materially differ from those estimates. Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates, including: expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes and management must select an amount that falls within that range of reasonable estimates. Significant estimates relied upon in preparing the accompanying consolidated financial statements include, among others: research and development expenses and related prepaid or accrued costs, the valuation of equity-based compensation awards and related expense.

Segments

The Company has one operating segment and one reporting unit. The Company’s chief operating decision maker, its Chief Executive Officer, manages the Company’s operations on a consolidated basis for the purposes of assessing performance and allocating resources. All of the Company’s assets are located in the United States.

Fair Value of Financial Instruments

The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. FASB ASC Topic 820, Fair Value Measurements and Disclosures (“ASC 820”), establishes a hierarchy of inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below:

Level 1—Valuations based on quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2—Valuations based on quoted prices for similar assets or liabilities in markets that are not active or for which all significant inputs are observable, either directly or indirectly.

Level 3—Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and unobservable.

To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement.

Items measured at fair value on a recurring basis as of September 30, 2025 include cash equivalents and marketable securities (Notes 3 and 4). The carrying amounts reflected in the accompanying consolidated balance sheets for prepaid expenses and other current assets, accounts payable and accrued expenses approximate their fair values due to their short-term nature.

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Property and Equipment, net

Property and equipment are recorded at cost. Depreciation is calculated using the straight-line method over the following estimated useful lives of the assets:


		ESTIMATED USEFUL LIFE
Furniture and fixtures		5 years
Lab equipment		5 years
IT equipment		3 years
Leasehold improvements		Shorter of the lease term or useful life

Upon disposal, retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the results of operations. Expenditures for repairs and maintenance that do not improve or extend the lives of the respective assets are charged to expense as incurred.

Research and Development Expense

Research and development costs are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including salaries and bonuses, overhead costs, contract services and other related costs. The value of goods and services received from contract research organizations and contract manufacturing organizations in the reporting period are estimated based on the level of services performed, and progress in the period in cases when the Company has not received an invoice from the supplier. In circumstances where amounts have been paid in excess of costs incurred, the Company records a prepaid expense. When billing terms under these contracts do not coincide with the timing of when the work is performed, the Company is required to make estimates of outstanding obligations to those third parties as of period end. Any accrual estimates are based on a number of factors, including the Company’s knowledge of the progress towards completion of the specific tasks to be performed, invoicing to date under the contracts, communication from the vendors of any actual costs incurred during the period that have not yet been invoiced and the costs included in the contracts. Significant judgments and estimates may be made in determining the accrued balances at the end of any reporting period. Actual results could differ from the estimates made by the Company.

Income Taxes

Income taxes are recorded in accordance with FASB ASC Topic 740, Income Taxes (“ASC 740”), which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse.

Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company makes estimates and judgments about future taxable income based on assumptions that are consistent with the Company’s plans and estimates. Should the actual amounts differ from these estimates, the amount of the Company’s valuation allowance could be materially impacted. Changes in these estimates may result in significant increases or decreases to the tax provision in a period in which such estimates are changed, which in turn would affect net income or loss.

The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit to the extent that the position is more likely than not to be sustained on examination by the taxing authorities based on the technical merits of the position as well as consideration of the available facts and circumstances. The Company records interest and penalties related to uncertain tax positions, if applicable, as a component of income tax expense.

Cash and Cash Equivalents

The Company considers all highly liquid investments purchased with original final maturities of three months or less from the date of purchase to be cash equivalents. Cash and cash equivalents include cash held in banks and amounts held in interest-bearing money market funds, U.S. treasury securities, U.S. Government agency securities, and commercial paper.

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Marketable Securities

The Company’s investments are comprised of U.S. government agency securities, U.S. treasury securities, commercial paper and corporate debt securities. Investments are classified at the time of purchase, based on management’s intent, as held-to-maturity, available-for-sale, or trading. All of the Company’s marketable security investments are classified as available-for-sale securities and are reported at fair market value using quoted prices in active markets for similar securities. The cost of securities sold is determined on a specific identification basis, and realized gains and losses are included as a component of other income within the condensed consolidated statements of operations and comprehensive loss. Unrealized gains and losses are included within the condensed consolidated statements of comprehensive loss.

The Company assesses its available-for-sale securities under the available-for-sale security impairment model in ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Statements as of each reporting date in order to determine if a portion of any decline in fair value below carrying value is the result of a credit loss for its available-for-sale securities. The Company records credit losses for its available-for-sale securities in the condensed consolidated statements of operations and comprehensive loss as credit loss expense, which is limited to the difference between the fair value and the amortized cost of the security. To date, the Company has not recorded any credit losses on its available-for-sale securities. Declines in fair value below carrying value attributable to non-credit related factors are recorded as accumulated other comprehensive loss, which is a separate component of stockholders’ equity.

The Company classifies its available-for-sale securities that mature within one year from the balance sheet date as current assets on the condensed consolidated balance sheets. Available-for-sale securities that mature more than one year from the balance sheet date are classified as non-current assets on the condensed consolidated balance sheets.

Leases

The Company determines the initial classification and measurement of its right-of-use assets and lease liabilities at the lease commencement date and thereafter if modified. The lease term includes any renewal options and termination options that the Company is reasonably assured to exercise. The present value of lease payments is determined by using the interest rate implicit in the lease, if that rate is readily determinable; otherwise, the Company uses its incremental borrowing rate. The incremental borrowing rate is determined by using the rate of interest that the Company would pay to borrow on a collateralized basis an amount equal to the lease payments for a similar term and in a similar economic environment.

Fixed lease expense for operating leases is recognized on a straight-line basis, unless the right-of-use assets have been impaired, over the reasonably assured lease term based on the total lease payments and is included in operating expenses in the statements of operations and comprehensive loss.

Equity-Based Compensation

The Company issues equity-based awards to employees, managers, executives, non-employees and service providers in the form of restricted common stock, restricted stock units, and stock options. The Company accounts for equity-based compensation awards in accordance with FASB ASC Topic 718, Compensation-Stock Compensation (“ASC 718”).

The fair value of the Company’s common stock underlying its equity awards is based on the quoted market price of the Company’s common stock on the grant date. The Company estimates the fair value of its stock options using the Black-Scholes option pricing model, which uses as inputs the fair value of the Company’s common stock, and certain management estimates, including the expected stock price volatility, the expected term of the award, the risk-free rate, and expected dividends. Expected volatility is calculated based on reported volatility data for a representative group of publicly traded companies for which historical information is available. The Company selects companies with comparable characteristics with historical share price information that approximates the expected term of the equity-based awards. The Company computes the historical volatility data using the daily closing prices for the selected companies’ shares during the equivalent period that approximates the calculated expected term of the stock options. The Company will continue to apply this method until a sufficient amount of historical information regarding the volatility of its stock price becomes available. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant commensurate with the expected term assumption. The Company uses the simplified method, under which the expected term is presumed to be the midpoint between the vesting date and the end of the contractual term. The Company utilizes this method due to lack of historical exercise data. The expected dividend yield is assumed to be zero as the Company has no current plans to pay any dividends on common stock. The fair value of the restricted stock units are based on the Company’s stock price on the date of the grant.

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The Company generally issues equity awards that are subject to either service-based vesting conditions and in limited instances, service-based and performance-based vesting conditions. Compensation expense for awards issued to grantees with service-based vesting conditions are recognized on a straight-line basis based on the grant date fair value over the associated requisite service period of the award, which is generally the vesting term. Compensation expense for awards to grantees with service-based and performance-based vesting conditions are recognized based on the grant-date fair value over the requisite service period using the accelerated attribution method to the extent achievement of the performance condition is probable. As of each reporting date, the Company estimates the probability that specified performance criteria will be met and does not recognize compensation expense until it is probable that the performance-based vesting condition will be achieved.

The Company evaluates whether an equity award should be classified and accounted for as a liability award or equity award for all equity-based compensation awards granted. As of September 30, 2025, all of the Company’s equity-based awards were equity classified. Forfeitures are recognized as they occur. The Company classifies equity-based compensation expense in the accompanying consolidated statements of operations and comprehensive loss in the same manner in which the award recipient’s salary and related costs are classified or in which the award recipient’s service payments are classified, as applicable.

Concentrations of Credit Risk and Significant Suppliers

Financial instruments that potentially expose the Company to credit risk primarily consist of cash, cash equivalents and marketable securities. The Company’s investment portfolio is comprised of money market funds, debt securities issued by U.S. government and corporate debt securities. The Company maintains its deposits with accredited financial institutions and, consequently, the Company does not believe it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Bank accounts in the United States are insured by the Federal Deposit Insurance Corporation (“FDIC”) up to $250,000. As of September 30, 2025 and December 31, 2024, predominantly all of the Company’s primary operating accounts significantly exceeded the FDIC limits.

The Company is dependent on third-party organizations to research, develop, manufacture and process its product candidates for its development programs. In particular, the Company currently relies on a limited number of third-party manufacturers for preclinical, clinical, and future commercial manufacturing activities. The Company expects to continue to be dependent on a small number of manufacturers to supply it with its requirements for all products. The Company’s research and development programs could be adversely affected by a significant interruption in the supply of the necessary materials.

Off-Balance Sheet Arrangements

As of September 30, 2025 and December 31, 2024, the Company had no off-balance sheet risks such as foreign exchange contracts, option contracts or other foreign hedging arrangements.

Comprehensive Loss

Comprehensive loss includes net loss as well as other changes in stockholders' equity that result from transactions and events other than those with stockholders. The Company’s unrealized gains and losses on marketable securities represent the only component of other comprehensive loss that are excluded from the reported net loss and that are presented in the condensed consolidated statements of comprehensive loss.

Net Loss Per Share

The Company has two classes of common stock outstanding comprised of voting and non-voting shares. The rights of the holders of voting and non-voting shares are identical, except with respect to voting and conversion. Each share of non-voting stock may be converted into one share of voting stock at any time at the option of the stockholder, subject to certain beneficial ownership limitations. Net loss per share for each class of common stock issued is the same as they are entitled to the same liquidation and dividend rights.

The Company calculates basic net loss per common share by dividing net loss by the weighted-average number of common shares outstanding for the period. The Company has generated a net loss in the periods presented so the basic and diluted net loss per share are the same as the inclusion of the potentially dilutive securities would be anti-dilutive.

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Marketable Securities

The following is a summary of the Company’s investing portfolio (in thousands):


	AS OF SEPTEMBER 30, 2025
			UNREALIZED
	COST		GAINS		LOSSES			FAIR VALUE
Marketable securities
Maturities within one year:
U.S. treasury securities	$	162,054	$	223	$	(2	)	$	162,275
Debt securities issued by U.S. government agencies		100,577		439		—			101,016
Commercial paper		51,758		23		—			51,781
Corporate debt securities		104,192		117		(6	)		104,303
Total maturities within one year		418,581		802		(8	)		419,375
Maturities between one and two years:
U.S. treasury securities	$	52,515	$	209	$	(4	)	$	52,720
Debt securities issued by U.S. government agencies		4,453		19		—			4,472
Corporate debt securities		4,438		11		(1	)		4,448
Total maturities between one and two years		61,406		239		(5	)		61,640
Total marketable securities	$	479,987	$	1,041	$	(13	)	$	481,015


	AS OF DECEMBER 31, 2024
			UNREALIZED
	COST		GAINS		LOSSES			FAIR VALUE
Marketable securities:
Maturities within one year:
U.S. treasury securities	$	158,332	$	469	$	(34	)	$	158,767
Debt securities issued by U.S. government agencies		115,425		169		—			115,594
Commercial paper		35,508		49		—			35,557
Corporate debt securities		68,831		146		(31	)		68,946
Total maturities within one year		378,096		833		(65	)		378,864
Maturities between one and two years:
U.S. treasury securities	$	90,330	$	109	$	(271	)	$	90,168
Debt securities issued by U.S. government agencies		102,707		470		(75	)		103,102
Corporate debt securities		17,232		—		(86	)		17,146
Total maturities between one and two years		210,269		579		(432	)		210,416
Total marketable securities	$	588,365	$	1,412	$	(497	)	$	589,280

As of September 30, 2025, the Company had 23 securities with a total fair market value of $52.2 million in an unrealized loss position. The Company does not intend to sell its investments before recovery of the amortized cost basis of its debt securities at maturity and no allowance for credit losses was recorded as of September 30, 2025 and December 31, 2024. Securities are evaluated at the end of each reporting period. The Company did not record any impairment related to its marketable securities during the nine months ended September 30, 2025 and 2024.

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Fair Value Measurements

The following table presents information about the Company’s financial assets and liabilities measured at fair value on a reoccurring basis and indicates the level of fair value hierarchy utilized to determine such values (in thousands):


	AS OF SEPTEMBER 30, 2025
	LEVEL 1		LEVEL 2		LEVEL 3		TOTAL
Cash equivalents:
Money market funds	$	82,683	$	—	$	—	$	82,683
Commercial paper		—		15,721		—		15,721
Marketable securities:
U.S. treasury securities		214,995		—		—		214,995
Debt securities issued by U.S. government agencies		—		105,488		—		105,488
Commercial paper		—		51,781		—		51,781
Corporate debt securities		—		108,751		—		108,751
Total	$	297,678	$	281,741	$	—	$	579,419


	AS OF DECEMBER 31, 2024
	LEVEL 1		LEVEL 2		LEVEL 3		TOTAL
Cash equivalents:
Money market funds	$	132,491	$	—	$	—	$	132,491
Marketable securities:
U.S. treasury securities		248,935		—		—		248,935
Debt securities issued by U.S. government agencies		—		218,696		—		218,696
Commercial paper		—		35,557		—		35,557
Corporate debt securities		—		86,092		—		86,092
Total	$	381,426	$	340,345	$	—	$	721,771

Prepaids and Other Assets

Prepaid expenses and other current assets consisted of the following (in thousands):


	SEPTEMBER 30, 2025		DECEMBER 31, 2024
Prepaid expenses	$	7,410	$	2,621
Interest receivable		4,479		4,697
Other current assets		919		1,742
Total	$	12,808	$	9,060

As of September 30, 2025, the Company had no restricted cash. As of December 31, 2024, the Company had restricted cash of $0.3 million held as a letter of credit for the benefit of a clinical research organization. The related letter of credit was classified within other non-current assets on the consolidated balance sheet as of December 31, 2024.

As of September 30, 2025, the Company had $8.5 million in long-term prepayments, made in conjunction with the Company's research and development activities, classified within other non-current assets. As of December 31, 2024, the Company had no long-term prepayments.

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Property and Equipment, net

Property and Equipment, net consisted of the following (in thousands):


	SEPTEMBER 30, 2025			DECEMBER 31, 2024
Lab equipment	$	1,407		$	1,285
Leasehold improvements		3,075			863
Furniture and fixtures		1,760			—
IT equipment		992			—
Less: Accumulated depreciation		(1,202	)		(189	)
Total	$	6,032		$	1,959

The Company recognized $0.4 million and $1.0 million of depreciation expense for the three and nine months ended September 30, 2025, respectively. The Company recognized an immaterial amount of depreciation expense for the three months ended September 30, 2024 and $0.1 million of depreciation expense for the nine months ended September 30, 2024.

Accrued Expenses

Accrued expenses consisted of the following (in thousands):


	SEPTEMBER 30, 2025		DECEMBER 31, 2024
Accrued external research and development expenses	$	7,371	$	4,957
Accrued manufacturing expenses		7,835		15,505
Accrued employee compensation		12,682		1,895
Accrued other		1,704		1,898
Total	$	29,592	$	24,255

Other Significant Agreements

Paragon Option and License Agreements

For the three months ended September 30, 2025, the Company had no research and development expense in connection with services provided by Paragon under the Option and License Agreements. For the nine months ended September 30, 2025, the Company recognized $0.1 million of research and development expense in connection with services provided by Paragon under the Option and License Agreements. For the three and nine months ended September 30, 2024, the Company recognized $2.4 million and $11.1 million, respectively, of research and development expense in connection with services provided by Paragon under the Option and License Agreements.

Option Agreements

In February 2022, the Company entered into an antibody discovery and option agreement with Paragon, which was subsequently amended in November 2022 (as amended, the “2022 Option Agreement”). Under the terms of the 2022 Option Agreement, Paragon identifies, evaluates and develops antibodies directed against certain mutually agreed therapeutic targets of interest to the Company. The 2022 Option Agreement initially included two selected targets, IL-13 and IL-4Rα, and was subsequently amended in November 2022 to include an additional selected target, OX40L. Under the 2022 Option Agreement, the Company has the exclusive option to, on a research program-by-research program basis, be granted an exclusive, worldwide license to all of Paragon’s right, title and interest in and to the intellectual property resulting from the applicable research program to develop, manufacture and commercialize the antibodies and products directed to the selected targets (each, an “Option”). From time to time, the Company can choose to add additional targets to the collaboration by mutual agreement with Paragon.

Pursuant to the terms of the 2022 Option Agreement, the parties initiated certain research programs that generally focused on a particular target (each, a “Research Program”). Each Research Program is aimed at discovering, generating, identifying and/or characterizing antibodies directed to the respective target. For each Research Program, the parties established a research plan that sets

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forth the activities that will be conducted, and the associated research budget (each, a “Research Plan”). Upon execution of the 2022 Option Agreement, the Company agreed with Paragon on an initial Research Plan that outlined the services that will be performed commencing at inception of the arrangement related to IL-13 and IL-4Rα. The Research Plan for OX40L was agreed to prior to December 31, 2022. The Company's exclusive option with respect to any future Research Program is exercisable at the Company's sole discretion at any time during the period beginning on the initiation of activities under the associated Research Program and ending a specified number of days following the delivery of the data package from Paragon related to the results of the Research Plan activities (the “Option Period”). There is no payment due upon exercise of an Option pursuant to the 2022 Option Agreement.

Unless terminated earlier, the 2022 Option Agreement shall continue in force on a Research Program-by-Research Program basis until the earlier of: (i) the end of the Option Period for such Research Program, as applicable, if such Option is not exercised by the Company; and (ii) the effective date of the license agreement for such Research Program if the Company exercises its Option with respect to such Research Program (the “2022 Term”). Upon the expiration of the 2022 Term for all then-existing Research Programs, under the 2022 Option Agreement, the 2022 Option Agreement will automatically expire in its entirety. The Company may terminate the 2022 Option Agreement or any Research Program at any time for any or no reason upon 30 days’ prior written notice to Paragon, provided that the Company must pay certain unpaid fees due to Paragon upon such termination, as well as any non-cancellable obligations reasonably incurred by Paragon in connection with its activities under any terminated Research Program. Each party has the right to terminate the 2022 Option Agreement or any Research Program upon (i) 30 days’ prior written notice of the other party’s material breach that remains uncured for the 30-day period and (ii) the other party’s bankruptcy.

In consideration for the exclusive options granted under the 2022 Option Agreement, the Company paid an upfront cash amount of $1.3 million and issued 1,250,000 common units to Paragon. Paragon was also entitled to up to an additional 3,750,000 of common units in exchange for the rights granted under the 2022 Option Agreement, which were issued in connection with the closings of the additional tranches of the Series A Preferred Unit financing. Under the 2022 Option Agreement, on a Research Program-by-Research Program basis following the finalization of the Research Plan for each respective Research Program, the Company is required to pay Paragon a nonrefundable fee in cash of $0.5 million. The Company is also obligated to compensate Paragon on a quarterly basis for its services performed under each Research Program based on the actual costs incurred.

In November 2023, the Company entered into an additional antibody discovery and option agreement with Paragon (the “2023 Option Agreement” and together with the 2022 Option Agreement, collectively, the “Option Agreements”). Under the terms of the 2023 Option Agreement, Paragon identifies, evaluates and develops antibodies directed against certain mutually agreed therapeutic targets of interest to the Company. The 2023 Option Agreement initially includes one target, TSLP. Under the 2023 Option Agreement, the Company has the exclusive option to, on a research program-by-research program basis, be granted an exclusive, worldwide license to all of Paragon’s right, title and interest in and to the intellectual property resulting from the applicable research program to develop, manufacture and commercialize the antibodies and products directed to the selected targets. From time to time, the Company can choose to add additional targets to the collaboration by mutual agreement with Paragon.

Pursuant to the terms of the 2023 Option Agreement, the parties may initiate Research Programs. Each Research Program will be aimed at discovering, generating, identifying and/or characterizing antibodies directed to the respective target. For each Research Program, the parties must establish a Research Plan. In January 2024, the Company and Paragon agreed on an initial Research Plan that outlined the services that will be performed commencing at inception of the arrangement related to TSLP. The Company's exclusive option with respect to each Research Program is exercisable at the Company's sole discretion at any time during the period beginning on the initiation of activities under the associated Research Program and ending a specified number of days following the delivery of the data package from Paragon related to the results of the Research Plan activities. There is no payment due upon exercise of an Option pursuant to the 2023 Option Agreement.

Under the 2023 Option Agreement, on a Research Program-by-Research Program basis following the finalization of the Research Plan for each respective Research Program, the Company is required to pay Paragon a nonrefundable fee in cash of $2.0 million. The Company is also obligated to compensate Paragon on a quarterly basis for its services performed under each Research Program based on the actual costs incurred. The Company expenses the service fees as the associated costs are incurred when the underlying services are rendered. In January 2024, the Company finalized the Research Plan with Paragon related to the TSLP target. As such, the Company made a one-time non-refundable payment of $2.0 million to Paragon in the first quarter of 2024.

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Unless terminated earlier, the 2023 Option Agreement shall continue in force on a Research Program-by-Research Program basis until the earlier of: (i) the end of the Option Period for such Research Program, as applicable, if such Option is not exercised by the Company; and (ii) the effective date of the license agreement for such Research Program if the Company exercises its Option with respect to such Research Program (the “2023 Term”). Upon the expiration of the 2023 Term for all then-existing Research Programs, under the 2023 Option Agreement, the 2023 Option Agreement will automatically expire in its entirety. The Company may terminate the 2023 Option Agreement or any Research Program at any time for any or no reason upon 30 days’ prior written notice to Paragon, provided that the Company must pay certain unpaid fees due to Paragon upon such termination, as well as any non-cancellable obligations reasonably incurred by Paragon in connection with its activities under any terminated Research Program. Each party has the right to terminate the 2023 Option Agreement or any Research Program upon (i) 30 days’ prior written notice of the other party’s material breach that remains uncured for the 30-day period and (ii) the other party’s bankruptcy.

License Agreements

In November 2022, the Company exercised its option available under the 2022 Option Agreement with respect to the IL-13 Research Program. Upon such exercise, the parties entered into an associated license agreement (the “IL-13 License Agreement”). In April 2023, the Company exercised its option available under the 2022 Option Agreement with respect to the IL- 4Rα Research Program and the OX40L Research Program. Upon such exercise, the parties entered into associated license agreements (the “IL-4Rα License Agreement” and the “OX40L License Agreement,” respectively). In August 2024, the Company exercised its option available under the 2023 Option Agreement with respect to the TSLP Research Program and entered into the associated license agreement (the “TSLP License Agreement” and collectively with the IL-13 License Agreement, the IL-4Rα License Agreement and the OX40L License Agreement, the “License Agreements”). Under the terms of the License Agreements, Paragon granted to the Company an exclusive, worldwide, royalty-bearing, sublicensable right and license with respect to certain information, patent rights and sequence information related to antibodies directed at the respective target to use, make, sell, import, export and otherwise exploit the antibodies directed at the respective target. Pursuant to the License Agreements, the Company granted to Paragon a similar license (except that such license the Company granted to Paragon is non-exclusive) to the respective licenses with respect to multispecific antibodies that are directed at the respective targets and one or more other antibodies. The Company was also granted a right of first negotiation with Paragon concerning the development, license and grant of rights to certain multispecific antibodies associated with each respective license. The Company is solely responsible for the continued development, manufacture and commercialization of products at its own cost and expense for each licensed target.

Under the IL-13 License Agreement, the IL-4Rα License Agreement and the OX40L License Agreement, the Company is obligated to pay Paragon up to $3.0 million upon the achievement of specific development and clinical milestones for the first product under each of the License Agreements that achieves such specified milestones, including a payment of $1.0 million upon the nomination of a development candidate and $2.0 million upon the first dosing of a human patient in a Phase 1 trial. Under the TSLP License Agreement, the Company is obligated to pay Paragon up to $28.0 million upon the achievement of specific development and clinical milestones for the first product, including a payment of $3.0 million upon the nomination of a development candidate and $5.0 million upon the first dosing of a human patient in a Phase 1 trial.

Upon execution of the IL‑13 License Agreement, the Company paid Paragon a $1.0 million fee for the nomination of a development candidate. In August 2023, the Company announced the dosing of its first participant in the Phase 1 trial of APG777 and made a milestone payment of $2.0 million in the fourth quarter of 2023. In November 2023, the Company finalized the nomination of a development candidate under the IL‑4Rα License Agreement and made a milestone payment of $1.0 million to Paragon in the fourth quarter of 2023. In March 2024, the Company announced the dosing of its first participant in a Phase 1 trial of APG808 and made a milestone payment of $2.0 million to Paragon in the first quarter of 2024. In May 2024, the Company finalized the nomination of a development candidate under the OX40L License Agreement and made a milestone payment of $1.0 million to Paragon in the second quarter of 2024. In August 2024, the Company announced the dosing of its first participant in the Phase 1 trial of APG990 and made a milestone payment of $2.0 million to Paragon in the third quarter of 2024. In October 2024, the Company finalized the nomination of a development candidate under the TSLP License Agreement and made a milestone payment of $3.0 million to Paragon in the fourth quarter of 2024. In December 2024, the Company announced the dosing of its first participant in the Phase 1 trial of APG333 and made a milestone payment of $5.0 million in the fourth quarter of 2024.

The Company is also obligated to pay royalties to Paragon equal to a low-single digit percentage of net sales of any products under each of the respective License Agreements, and Paragon has a similar obligation to pay royalties to the Company with respect to each of the multispecific licenses. Royalties are due on a product-by-product and country-by-country basis beginning upon the first commercial sale of each product and ending on the later of (i) 12 years after the first commercial sale of such product in such country and (ii) expiration of the last valid claim of a patent covering such product in such country (the “Royalty Term”).

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Unless earlier terminated, the License Agreements remain in effect until the expiration of the last-to-expire Royalty Term for any and all products associated with the respective license. The Company may terminate the agreement in its entirety or on a country-by-country or product-by-product at any time for any or no reason upon 60 days’ advance written notice to Paragon, and either party may terminate for (i) the other party’s material breach that remains uncured for 90 days (or 30 days with respect to any failure to make payments) following notice of such breach and (ii) the other party’s bankruptcy. Upon any termination prior to the expiration of a License Agreement, all licenses and rights granted pursuant to such License Agreement will automatically terminate and revert to the granting party and all other rights and obligations of the parties will terminate.

The Company concluded that each of the License Agreements constitutes an asset acquisition of in-process research and development assets with no alternative future use. Each of the arrangements did not qualify as a business combination because substantially all of the fair value of the assets acquired was concentrated in the license which comprises a single identifiable asset. Therefore, the aggregate acquisition cost for each license was recognized as research and development expense.

Biologics Master Services Agreement — WuXi Biologics (Hong Kong) Limited

In June 2022, Paragon and WuXi Biologics (Hong Kong) Limited (“WuXi Biologics”) entered into a biologics master services agreement (the “WuXi Biologics MSA”), which was subsequently novated to the Company by Paragon in the second quarter of 2023. The WuXi Biologics MSA governs all development activities and GMP manufacturing and testing for APG777, APG990, APG333 and APG808, as well as potential future product candidates, on a work order basis. Under the WuXi Biologics MSA, the Company is obligated to pay WuXi Biologics a service fee and all non-cancellable obligations in the amount specified in each work order associated with the agreement for the provision of services.

The WuXi Biologics MSA terminates on the later of (i) June 20, 2027 or (ii) the completion of services under all work orders executed by the parties prior to June 20, 2027, unless terminated earlier. The term of each work order terminates upon completion of the services under such work order, unless terminated earlier. The Company can terminate the WuXi Biologics MSA or any work order at any time upon 30 days’ prior written notice and immediately upon written notice if WuXi Biologics fails to obtain or maintain required material governmental licenses or approvals. Either party may terminate a work order (i) at any time upon six months’ prior notice with reasonable cause, provided however that if WuXi Biologics terminates a work order in such manner, no termination or cancellation fees shall be paid by the Company and (ii) immediately for cause upon (a) the other party’s material breach that remains uncured for 30 days after notice of such breach, (b) the other party’s bankruptcy or (c) a force majeure event that prevents performance for a period of at least 90 days.

For the three and nine months ended September 30, 2025, the Company recognized $1.6 million and $6.1 million, respectively, of research and development expense in connection with the WuXi Biologics MSA. For the three and nine months ended September 30, 2024, the Company recognized $14.7 million and $27.9 million, respectively, of research and development expense in connection with the WuXi Biologics MSA.

Cell Line License Agreement — WuXi Biologics (Hong Kong) Limited

In June 2022, Paragon and WuXi Biologics entered into a cell line license agreement (the “Cell Line License Agreement”), which was subsequently novated to the Company by Paragon in the second quarter of 2023. Under the Cell Line License Agreement, the Company received a non-exclusive, worldwide, sublicensable license to certain of WuXi Biologics’ know-how, cell line, biological materials (the “WuXi Biologics Licensed Technology”) and media and feeds to make, have made, use, sell and import certain therapeutic products produced through the use of the cell line licensed by WuXi Biologics under the Cell Line License Agreement (the “WuXi Biologics Licensed Products”). Specifically, the WuXi Biologics Licensed Technology is used to manufacture the Company’s APG777, APG990, APG333 and APG808 product candidates.

In consideration for the license, the Company paid WuXi Biologics a non-refundable license fee of $150,000. Additionally, if the Company manufactures all of its commercial supplies of bulk drug product with a manufacturer other than WuXi Biologics or its affiliates, the Company is required to make royalty payments to WuXi Biologics in an amount equal to a fraction of a single digit percentage of global net sales of WuXi Biologics Licensed Products manufactured by a third-party manufacturer (the “Royalty”). If the Company manufactures part of its commercial supplies of the WuXi Biologics Licensed Products with WuXi Biologics or its affiliates, then the Royalty will be reduced accordingly on a pro rata basis.

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The Cell Line License Agreement will continue indefinitely unless terminated (i) by the Company upon six months’ prior written notice and the Company's payment of all undisputed amounts due to WuXi Biologics through the effective date of termination, (ii) by WuXi Biologics for a material breach by the Company that remains uncured for 60 days after written notice, (iii) by WuXi Biologics if the Company fails to make a payment and such failure continues for 30 days after receiving notice of such failure, or (iv) by either party upon the other party’s bankruptcy.

Master Services Agreement and Project Specific Agreements — Samsung Biologics Limited

In March 2025, the Company entered into a Master Services Agreement (the “Samsung Biologics MSA”), made effective as of February 28, 2025, with Samsung Biologics Co., Ltd. (“Samsung Biologics”), pursuant to which Samsung Biologics will manufacture and supply the Company with APG777 drug substance (the “Samsung Biologics Product”) for clinical development and commercial sale, if approved. The Company is obligated to pay Samsung Biologics service fees for each manufactured batch, as well as the costs of materials purchased by Samsung Biologics and expenses including testing and storage, which such costs and fees will be specified in Project Specific Agreements (each a “PSA”).

Also in March 2025, the Company entered into a PSA (the “Initial PSA”) with Samsung Biologics, made effective as of February 28, 2025, pursuant to which Samsung Biologics will produce clinical batches of the Samsung Biologics Product at its facility in Incheon, South Korea, perform process characterization and validation, and manufacture process performance qualification lots of the Samsung Biologics Product. Under the Initial PSA, the Company must purchase certain minimum quantities of the Samsung Biologics Product and has agreed to pay Samsung Biologics as determined pursuant to the terms of the Initial PSA. The Company has also agreed to enter into a separate PSA with Samsung Biologics for the manufacture of commercial supply of APG777 drug substance, which will provide for certain minimum purchase commitments for each year from 2029 to 2034. If the Company elects not to enter into the PSA for commercial supply, it will incur an exit fee in the high single digit millions.

The Samsung Biologics MSA will terminate in February 2035, or, if a PSA is still in effect, when such PSA terminates, and may be extended upon mutual agreement of the parties. The Initial PSA will terminate in December 2034. Either the Company or Samsung Biologics may terminate the Samsung Biologics MSA or the Initial PSA in the event of an uncured material breach by, insolvency of or inability to perform due to a force majeure event by the other party. In the event all applicable PSAs have been terminated, Samsung Biologics has agreed to provide assistance with certain technology transfer matters, subject to exceptions. If the Company terminates the Samsung Biologics MSA or Initial PSA without cause, the Company will generally be responsible for paying the purchase price for the Company’s aggregate product commitment for the remainder of the term, less any amounts the Company has already paid.

For the three and nine months ended September 30, 2025, the Company recognized $5.0 million and $12.4 million, respectively, of research and development expense in connection with the Samsung Biologics MSA.

Commitments and Contingencies

Other Contracts

Currently, all of the Company’s preclinical and clinical drug manufacturing, storage, distribution or quality testing are outsourced to third-party manufacturers. As development programs progress and new process efficiencies are built, the Company expects to continually evaluate this strategy with the objective of satisfying demand for registration trials and, if approved, the manufacture, sale and distribution of commercial products. Under such agreements, the Company is contractually obligated to make certain payments to vendors upon early termination, primarily to reimburse them for their unrecoverable outlays incurred prior to cancellation as well as any amounts owed by the Company prior to early termination. The actual amounts the Company could pay in the future to the vendors under such agreements may differ from the purchase order amounts due to cancellation provisions.

Indemnification Agreements

The Company enters into standard indemnification agreements and/or indemnification sections in other agreements in the ordinary course of business. Pursuant to the agreements, the Company indemnifies, holds harmless, and agrees to reimburse the indemnified party for losses suffered or incurred by the indemnified party, generally the Company’s business partners. The term of these indemnification agreements is generally perpetual any time after execution of the agreement. There is no limit to the maximum potential amount of future payments the Company could be required to make under these indemnification agreements. As of September 30, 2025, the Company has not incurred costs to defend lawsuits or settle claims related to these indemnification agreements. The Company was not aware of any claims under these indemnification arrangements as of September 30, 2025 and December 31, 2024.

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Legal Proceedings

The Company is not currently party to any material legal proceedings. At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of FASB ASC Topic 450, Contingencies (“ASC 450”). The Company expenses as incurred the costs related to its legal proceedings.

10.

Common Stock

In July 2023, the Company completed its IPO, selling an aggregate 20,297,500 shares of common stock. All outstanding preferred units were exchanged into 24,987,750 shares of common stock in connection with the IPO. Following the IPO, the Company is authorized to issue up to 400,000,000 shares of common stock, par value $0.00001.

In March 2024, the Company issued and sold an aggregate of 7,790,321 shares of its common stock in an underwritten public offering.

In August 2024, the Company entered into an Open Market Sale Agreement (the “Sale Agreement”) with Jefferies LLC (the “Sales Agent”), pursuant to which the Company may offer and sell shares of common stock up to a maximum aggregate offering price of $300.0 million through an at-the-market offering program. The Sales Agent will be entitled to compensation at a commission of up to 3.0% of the aggregate gross sales price per share sold under the Sale Agreement, unless otherwise agreed to by the Sales Agent and the Company under the Sale Agreement. In December 2024, the Company sold 926,049 shares of common stock under the Sale Agreement at a price per share of $48.50. During the three months ended September 30, 2025, the Company sold 527,437 shares of common stock under the ATM for gross proceeds of $20.0 million, less commissions and other offering expenses of $0.6 million. As of September 30, 2025, $235.1 million remained available for sale under the Sale Agreement.

See Note 16 for information on common stock issued in conjunction with the October 2025 Offering.

As of September 30, 2025, 60,147,727 and 59,315,738 shares of common stock were issued and outstanding, respectively. The 60,147,727 shares of common stock issued are comprised of 46,661,085 shares of voting common stock and 13,486,642 shares of non-voting common stock. As of September 30, 2025, there were 831,989 shares of unvested restricted common stock included within the shares of common stock issued.

As of December 31, 2024, 59,478,725 and 58,062,898 shares of common stock were issued and outstanding, respectively. The 59,478,725 shares of common stock issued are comprised of 45,992,083 shares of voting common stock and 13,486,642 shares of non-voting common stock. As of December 31, 2024, there were 1,415,827 shares of unvested restricted common stock included within the shares of common stock issued.

11.

Equity-Based Compensation

Restricted Common Stock

Concurrent with the Reorganization, all outstanding incentive units were exchanged into 3,469,546 shares of common stock, of which 2,779,358 were unvested restricted common stock. The following table provides a summary of the unvested restricted common stock award activity during the nine months ended September 30, 2025:


	NUMBER OF SHARES			WEIGHTED- AVERAGE GRANT DATE FAIR VALUE PER SHARE
Unvested restricted common stock as of December 31, 2024		1,415,827		$	5.30
Vested		(583,341	)	$	4.98
Forfeited		(497	)	$	13.08
Unvested restricted common stock as of September 30, 2025		831,989		$	5.52

The fair value of restricted stock vested during the three and nine months ended September 30, 2025 was $1.0 million and $2.9 million, respectively.

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Stock Options and Restricted Stock Units

In July 2023, in connection with the IPO, the Company’s Board of Directors (the “Board”) and stockholders approved the 2023 Equity Incentive Plan (the “2023 Plan”), which became effective on the date of the effectiveness of the registration statement for the IPO. The 2023 Plan provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, awards of restricted stock, restricted stock units and other stock-based awards. As of September 30, 2025, the number of shares of common stock available for future grants under the 2023 Plan is equal to 6,041,663 shares of common stock. The number of shares available for grant and issuance under the 2023 Plan will be automatically increased on January 1 of each year by a number of shares equal to up to 5% of the outstanding shares of common stock on such date.

The Company uses the Black-Scholes option pricing model to estimate the fair value of stock options granted with the following assumptions:


	THREE MONTHS ENDED SEPTEMBER 30,	NINE MONTHS ENDED SEPTEMBER 30,
	2025	2025
Risk-free interest rate	3.8% - 4.1%	3.8% - 4.4%
Expected dividend yield	0.0%	0.0%
Expected term (in years)	6.0 - 6.25	5.5 - 6.25
Expected volatility	74.3% - 74.7%	74.3% - 75.5%

The following table provides a summary of stock option activity during the nine months ended September 30, 2025:


	OPTIONS			WEIGHTED- AVERAGE EXERCISE PRICE		WEIGHTED- AVERAGE REMAINING CONTRACTUAL TERM (IN YEARS)		AGGREGATE INTRINSIC VALUE (IN THOUSANDS)
Outstanding as of December 31, 2024		5,155,414		$	35.12		9.4	$	61,506
Granted		810,997		$	39.05		—		—
Exercised		(65,672	)	$	20.74		—		—
Forfeited		(211,940	)	$	32.00		—		—
Outstanding as of September 30, 2025		5,688,799		$	35.96		8.8	$	43,934
Exercisable as of September 30, 2025		1,670,334		$	30.27		8.4	$	20,354

The fair value of options vested during the three and nine months ended September 30, 2025 was $10.5 million and $28.3 million, respectively.

The following table provides a summary of the unvested restricted stock unit activity under the 2023 Plan during the nine months ended September 30, 2025:


	NUMBER OF SHARES			WEIGHTED- AVERAGE GRANT DATE FAIR VALUE PER SHARE
Unvested restricted stock units as of December 31, 2024		267,564		$	38.48
Vested		(54,820	)		36.63
Forfeited		(16,612	)		36.34
Unvested restricted stock units as of September 30, 2025		196,132		$	39.18

The fair value of restricted stock units vested during the three and nine months ended September 30, 2025 was $0.6 million and $2.0 million, respectively.

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2023 Employee Stock Purchase Plan

In July 2023, the Board adopted and the Company’s stockholders approved the 2023 Employee Stock Purchase Plan (the “ESPP”), which became effective on July 13, 2023. The ESPP provides that eligible employees may contribute up to 15% of their eligible earnings toward the semi-annual purchase of the Company's common stock, subject to any plan limitations. The purchase period under the ESPP has a duration of six months, and the purchase price with respect to each purchase period is equal to 85% of the lesser of (i) the fair market value of the Company's common stock at the commencement of the applicable six-month purchase period or (ii) the fair market value of the Company's common stock on the exercise date. As of September 30, 2025, 49,221 shares have been issued under the ESPP and 1,493,797 shares remain available for issuance.

The following table presents the classification of equity-based compensation expense related to equity awards granted to employees, managers, executives, and service providers (in thousands):


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
	2025		2024		2025		2024
Research and development expense	$	5,730	$	2,464	$	16,640	$	6,548
General and administrative expense		6,147		3,375		17,707		9,175
Total	$	11,877	$	5,839	$	34,347	$	15,723

As of September 30, 2025, the total unrecognized compensation expense related to the Company’s stock options, unvested restricted stock and ESPP was $118.0 million, which the Company expects to recognize over a weighted-average period of approximately 2.5 years.

In August 2023, the Board approved two option grants to the new Chairman of the Board, (1) to purchase 50,000 shares of the Company’s common stock under the 2023 Plan (“first option”), and (2) to purchase 100,000 shares of the Company’s common stock outside of the 2023 Plan (“second option”), in which the shares underlying both options will vest and become exercisable in equal monthly installments over a three-year period from August 2023. The second option was contingent upon approval of the shares underlying the award by the Company’s stockholders at the 2024 Annual Meeting of Stockholders and failure to obtain stockholder approval would have resulted in the forfeiture of the award. Prior to receiving stockholder approval for the second option, neither a grant date nor a service inception date occurred, and no compensation cost was recognized for the award. In June 2024, the Company's stockholders approved the shares underlying the second option at the 2024 Annual Meeting of Stockholders. Therefore, a cumulative catch-up in equity-based compensation was recognized during the second quarter of 2024.

12.

Related Parties

Under the Option Agreements and the License Agreements, Paragon, a stockholder of the Company that was founded by a Series A Preferred Unit investor, received upfront consideration in the form of common units, is entitled to receive milestone and royalty payments upon specific conditions and receives payments from the Company for providing ongoing services under the agreements (see Note 8). As of September 30, 2025, the Company had no amounts due to Paragon. As of December 31, 2024, $0.1 million was due to Paragon. For the three months ended September 30, 2025, the Company incurred no research and development expenses with Paragon and $0.1 million for the nine months ended September 30, 2025. For the three and nine months ended September 30, 2024, the Company incurred research and development expenses of $2.4 million and $11.1 million, respectively, with Paragon.

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13.

Net Loss Per Share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share data):


	THREE MONTHS ENDED SEPTEMBER 30,		NINE MONTHS ENDED SEPTEMBER 30,
	2025	2024	2025	2024
Numerator:

Apogee Therapeutics, Inc. 10-Q