0001104659-26-058650 | 10-Q | XBRL Viewer

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2026

Schedule of company's financial assets measured at fair value on a recurring basis

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


	March 31, 2026
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Level 1		Level 2		Level 3

Money market funds	$	40,127	$	—	$	—	$	40,127	$	40,127	$	—	$	—
Corporate securities		110,131		16		(124)		110,023		26,831		83,192		—
Government securities		154,419		28		(192)		154,255		—		154,255		—
Total assets measured at fair value	$	304,677	$	44	$	(316)	$	304,405	$	66,958	$	237,447	$	—


	December 31, 2025
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Level 1		Level 2		Level 3

Money market funds	$	40,494	$	—	$	—	$	40,494	$	40,494	$	—	$	—
Corporate securities		105,373		78		(25)		105,426		16,347		89,079		—
Government securities		161,882		116		(143)		161,855		—		161,855		—
Total assets measured at fair value		307,749		194		(168)	$	307,775	$	56,841	$	250,934	$	—

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2026	May 08, 2026
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Transition Report	false
Securities Act File Number	001-41929
Entity Registrant Name	ARRIVENT BIOPHARMA, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	86-3336099
Entity Address, Address Line One	18 Campus Boulevard Suite 100
Entity Address, City or Town	Newtown Square
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19073
City Area Code	628
Local Phone Number	277-4836
Title of 12(b) Security	Common Stock, $0.0001 Par Value per Share
Trading Symbol	AVBP
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		46,574,928
Entity Central Index Key	0001868279
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q1
Amendment Flag	false

Debt

3 Months Ended

Mar. 31, 2026

Debt

Debt

(11) Debt

On May 8, 2025, the Company entered into a Loan and Security Agreement (the “Loan Agreement”) between the Company, as borrower (the “Borrower”) and Silicon Valley Bank, a Division of First-Citizens Bank & Trust Company (the “Bank”), pursuant to which, the Bank agreed to extend up to $75.0 million to the Company (the “Term Loan”), consisting of: (i) a first tranche commitment of $35.0 million to be drawn at the Company’s option, subject to the satisfaction of certain conditions, (ii) a second tranche commitment of up to $15.0 million to be drawn at the Company’s option, subject to the satisfaction of certain conditions, and (iii) at the Company’s option, subject to the satisfaction of certain conditions, a third tranche commitment of $25.0 million. If not drawn, each tranche commitment is subject to an expiration date. In March 2026, the Company entered into an amendment of the Loan Agreement in which one of the conditions of the second tranche commitment was eliminated. No amounts have been drawn on this Term Loan as of March 31, 2026.

The Term Loan matures on March 1, 2030 (or, if the Borrower does not satisfy certain conditions, on March 1, 2029) unless otherwise accelerated following the occurrence and continuation of an event of default pursuant to the terms of the Loan Agreement. Amounts borrowed under the Term Loan bear interest at a variable annual rate equal to the greater of (i) 6.00%, and (ii) (A) the Prime Rate, minus (B) 0.75%. The Borrowers may, at their option, prepay the Term Loan subject to a prepayment premium.

The Borrower’s obligations are secured by a first priority, perfected lien on substantially all the property and assets of the Borrower, except for intellectual property (other than the security interest in proceeds from any intellectual property) and certain other customary excluded assets as set forth therein.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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+ Details

Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2026

Summary of Significant Accounting Policies

Interim Financial Statements

(a)	Interim Financial Statements

The accompanying unaudited condensed interim financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). Any references in these notes to applicable guidance are meant to refer to GAAP as found in Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) promulgated by the Financial Accounting Standards Board (“FASB”).

In the opinion of the Company, the accompanying unaudited condensed financial statements contain all adjustments, consisting of only normal recurring adjustments, necessary for a fair statement of its financial position as of March 31, 2026, and its results of operations for the three months ended March 31, 2026 and 2025, and cash flows for the three

months ended March 31, 2026 and 2025. The condensed balance sheet at December 31, 2025, was derived from audited annual financial statements but does not contain all of the footnote disclosures from the annual financial statements.

Use of Estimates

(b)	Use of Estimates

The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from such estimates. Estimates and assumptions are periodically reviewed, and the effects of revisions are reflected in the financial statements in the period they are determined to be necessary.

Significant areas that require the Company’s estimates include the fair value of the Company’s common stock prior to the completion of the Company’s initial public offering, and accrued research and development expenses.

Fair Value Measurements

(c)	Fair Value Measurements

The Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The Company determines fair value based on assumptions that market participants would use in pricing an asset or liability in the principal or most advantageous market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following levels:

•

Level 1 Inputs: Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date.

•

Level 2 Inputs: Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability.

•

Level 3 Inputs: Unobservable inputs for the asset or liability used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at the measurement date.

The Company believes that the carrying amounts of the Company’s financial instruments, principally cash equivalents and accounts payable, approximate fair value due to the short-term nature of those instruments.

Net Loss per Share

(d)	Net Loss per Share

Basic net loss per share of common stock is computed by dividing net loss by the weighted-average number of shares of common stock outstanding during each period. Pre-funded warrants were included in the denominator as the exercise price is negligible and these warrants are fully vested and exercisable. Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred stock and stock options, which would result in the issuance of incremental shares of common stock. For diluted net loss per share, the weighted-average number of shares of common stock is the same for basic net loss per share since when a net loss exists, potentially dilutive securities are not included in the calculation as their impact is anti-dilutive. The Company’s convertible preferred stock entitled the holder to participate in dividends and earnings of the Company, and, if the Company had recognized net income, it would have used the two-class method to calculate earnings per share. The two-class method was not applicable during periods with a net loss, as the holders of the convertible preferred stock had no obligation to fund losses.

The following table sets forth the computation of net loss per share, basic and diluted (in thousands, except share and per share data):


	Three Months Ended
	March 31,
	2026		2025
Numerator:
Net loss	$	(43,320)	$	(64,387)
Denominator:
Weighted-average shares of common stock outstanding		43,755,706		—
Weighted-average pre-funded warrants outstanding (1)		1,311,952		—
Weighted-average shares of common stock outstanding, basic and diluted		45,067,658		33,898,870

Net loss per share attributable to common stockholders, basic and diluted	$	(0.96)	$	(1.90)

(1)Represents the weighted average number of common shares issuable upon the exercise of pre-funded warrants issued in 2025, which are considered to be outstanding for the purposes of the basic and diluted net loss per share calculation from the date of issuance due to their nominal exercise price ($0.0001).

Stock options outstanding have been excluded from the computation of diluted weighted-average shares of common stock outstanding, as they would be anti-dilutive. Stock options outstanding at March 31, 2026 and 2025 were 7,220,584 and 4,059,300, respectively.

Accounting Pronouncements Not Yet Adopted

(e)	Accounting Pronouncements Not Yet Adopted

In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures: Disaggregation of Income Statement Expenses. This standard requires the disclosure of more detailed information about the types of expenses in commonly presented expense captions, such as research and development, and general and administrative expenses. This standard will be effective for annual periods beginning after December 15, 2026 and interim periods beginning after December 15, 2027 and may be applied either prospectively or retrospectively. The Company is currently evaluating the impact that this standard may have on its financial statements.

License and Collaboration Agreements

(f) License and Collaboration Agreements

The Company analyzes its license and collaborative agreements to assess whether they are within the scope of ASC 808, Collaborative Arrangements (“ASC 808”) to determine whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards that are dependent on the commercial success of such activities. To the extent the arrangement is within the scope of ASC 808, the Company assesses whether aspects of the arrangement are within the scope of other accounting literature. If the Company concludes that some or all aspects of the arrangement represent a transaction with a customer, it accounts for those aspects of the arrangement within the scope of ASC 606, Revenue from Contracts with Customers. None of the license and collaboration agreements discussed in Note 8 represent transactions with customers.

If the Company concludes that some or all aspects of the arrangement are within the scope of ASC 808 and do not represent a transaction with a customer, it recognizes costs incurred as a component of the related expense in the period incurred. The arrangements may also require the Company to make payments on achievement of certain milestones, including clinical, regulatory, and development milestones. Clinical, regulatory, and development milestones are recognized as research and development expense only when such milestones are deemed probable of being achieved.

Other Comprehensive Income (Loss)

(g) Other Comprehensive Income (Loss)

Other comprehensive income (loss) (“OCI”) consists of expenses, gains, and losses that are excluded from net income under GAAP. The Company’s OCI includes, when applicable, unrealized gains and losses on available-for-sale debt securities.

Unrealized gains and losses on available-for-sale debt securities are recorded net of tax in accumulated other comprehensive income (loss) (“AOCI”), a component of stockholders’ equity, until realized. Upon realization, these amounts are reclassified from AOCI into earnings.

- Definition

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

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+ Details

CONDENSED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 62,103	$ 45,540
Short-term investments	264,277	267,281
Prepaid expenses and other current assets	22,320	20,076
Total current assets	348,700	332,897
Right of use assets - operating leases	370	13
Deferred offering costs	69	69
Other assets	156	190
Total assets	349,295	333,169
Current liabilities:
Accounts payable	8,727	5,934
Accrued expenses	16,169	19,997
Operating lease liabilities	99	14
Total current liabilities	24,995	25,945
Operating lease liabilities, net of current amount	320
Total liabilities	25,315	25,945
Commitments and contingencies (Note 8)
Stockholders' equity:
Preferred stock $0.0001 par value, 10,000,000 shares authorized; no shares issued and outstanding
Common stock $0.0001 par value, 200,000,000 shares authorized; 45,308,941 and 42,452,251 shares issued and outstanding at March 31, 2026 and December 31, 2025, respectively	5	4
Additional paid-in capital	772,206	711,847
Accumulated deficit	(447,961)	(404,641)
Accumulated other comprehensive income (loss)	(270)	14
Total stockholders' equity	323,980	307,224
Total liabilities and stockholders' equity	$ 349,295	$ 333,169

Commitments, Contingencies, and Collaborations - Lepu (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 21, 2025	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025
Agreement
Research and development		$ 37,617		$ 61,289
License Agreement \| Lepu Biopharma
Agreement
Cash payment	$ 40,000
Maximum amount payable upon achievement of development and regulatory milestones		300,000
Maximum amount payable upon achievement of commercial milestones		890,000
Milestone payments paid		6,000	$ 1,000
Research and development		$ 800		$ 0

Stock-based Compensation - Summary of stock options activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Options
Outstanding as of beginning of period (in shares)	4,328,880
Granted (in shares)	2,950,250
Exercised (in shares)	(31,195)
Forfeited/Expired (in shares)	(27,351)
Outstanding as of end of period (in shares)	7,220,584
Exercisable (in shares)	1,986,886
Vested and expected to vest (in shares)	7,220,584
Weighted average exercise price
Outstanding as of beginning of period (in dollars per shares)	$ 15.56
Granted (in dollars per shares)	22.62
Exercised (in dollars per shares)	5.15
Forfeited/Expired (in dollars per shares)	9.46
Outstanding as of end of period (in dollars per shares)	18.48
Exercisable (in dollars per shares)	9.95
Vested and expected to vest (in dollars per shares)	$ 18.48
Weighted average remaining contractual term (years) and Aggregate Intrinsic Value
Weighted average remaining contractual term - Outstanding (years)	8 years 8 months 4 days
Weighted average remaining contractual term - Exercisable (years)	7 years 1 month 2 days
Weighted average remaining contractual term - Vested and expected to vest (years)	8 years 8 months 4 days
Aggregate Intrinsic Value - Outstanding (in dollars)	$ 40,051
Aggregate Intrinsic Value - Exercisable (in dollars)	27,924
Aggregate Intrinsic Value - Vested and expected to vest (in dollars)	$ 40,051
Weighted-average grant-date fair value of options (in dollars per share)	$ 16.98	$ 22.04

Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Prepaid Expenses and Other Current Assets
Research and development	$ 20,828	$ 19,830
Professional fees	480	3
Insurance	952	183
Other	60	60
Total	$ 22,320	$ 20,076

CONDENSED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Common stock	Additional paid-in capital	Accumulated Other Comprehensive (Loss)	Accumulated deficit	Total
Beginning balance at Dec. 31, 2024	$ 3	$ 496,195	$ (211)	$ (238,333)	$ 257,654
Beginning balance (in shares) at Dec. 31, 2024	33,706,765
Changes in stockholder's equity
Issuance of common stock, net of issuance costs	$ 1	6,516			6,517
Issuance of common stock, net of issuance costs (in shares)	264,458
Exercise of stock options		293			293
Exercise of stock options (in shares)	69,773
Stock-based compensation expense		2,271			2,271
Unrealized loss on marketable securities			194		194
Net Income (Loss)				(64,387)	(64,387)
Ending balance at Mar. 31, 2025	$ 4	505,275	(17)	(302,720)	202,542
Ending balance (in shares) at Mar. 31, 2025	34,040,996
Beginning balance at Dec. 31, 2025	$ 4	711,847	14	(404,641)	307,224
Beginning balance (in shares) at Dec. 31, 2025	42,452,251
Changes in stockholder's equity
Issuance of common stock, net of issuance costs	$ 1	54,724			54,725
Issuance of common stock, net of issuance costs (in shares)	2,425,495
Exercise of stock options		150			$ 150
Exercise of stock options (in shares)	31,195				31,195
Exercise of pre-funded warrants (in shares)	400,000				400,000
Stock-based compensation expense		5,485			$ 5,485
Unrealized loss on marketable securities			(284)		(284)
Net Income (Loss)				(43,320)	(43,320)
Ending balance at Mar. 31, 2026	$ 5	$ 772,206	$ (270)	$ (447,961)	$ 323,980
Ending balance (in shares) at Mar. 31, 2026	45,308,941

Commitments, Contingencies, and Collaborations - Aarvik (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Aug. 31, 2024	Mar. 31, 2026	Mar. 31, 2025	Jun. 30, 2023
Agreement
Research and development		$ 37,617	$ 61,289
Collaborative Agreement \| Aarvik
Agreement
Maximum payment on statements of work				$ 3,100
Initiation fee				$ 300
Amount of payment to exercise option to license and/or acquire certain intellectual property	$ 1,000
Maximum amount payable per product upon achievement of certain clinical and regulatory milestone events	18,000
Maximum amount payable per product upon achievement of commercial milestones	$ 80,000
Maximum amount of initiation and research fees to be paid		5,400
Research and development		$ 0	$ 100

Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value Measurements
Gross Unrealized Gains	$ 44	$ 194
Gross Unrealized Losses	(316)	(168)
Cash balance	21,900	5,000
Available for sale securities, Maturity dates within the next twelve months	264,300
Corporate securities
Fair Value Measurements
Gross Unrealized Gains	16	78
Gross Unrealized Losses	(124)	(25)
Government securities
Fair Value Measurements
Gross Unrealized Gains	28	116
Gross Unrealized Losses	(192)	(143)
Amortized Cost
Fair Value Measurements
Money market funds	40,127	40,494
Total assets measured at fair value	304,677	307,749
Amortized Cost \| Corporate securities
Fair Value Measurements
Securities, Carrying Value	110,131	105,373
Amortized Cost \| Government securities
Fair Value Measurements
Securities, Carrying Value	154,419	161,882
Fair Value
Fair Value Measurements
Money market funds	40,127	40,494
Total assets measured at fair value	304,405	307,775
Fair Value \| Corporate securities
Fair Value Measurements
Securities, Fair Value	110,023	105,426
Fair Value \| Government securities
Fair Value Measurements
Securities, Fair Value	154,255	161,855
Fair Value \| Level 1
Fair Value Measurements
Money market funds	40,127	40,494
Total assets measured at fair value	66,958	56,841
Fair Value \| Level 1 \| Corporate securities
Fair Value Measurements
Securities, Fair Value	26,831	16,347
Fair Value \| Level 2
Fair Value Measurements
Total assets measured at fair value	237,447	250,934
Fair Value \| Level 2 \| Corporate securities
Fair Value Measurements
Securities, Fair Value	83,192	89,079
Fair Value \| Level 2 \| Government securities
Fair Value Measurements
Securities, Fair Value	$ 154,255	$ 161,855

Development Stage Risks and Liquidity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Development Stage Risks and Liquidity
Accumulated deficit	$ 447,961	$ 404,641
Cash and cash equivalents, and short and long-term investments	$ 326,400
Substantial doubt about ability to continue as going concern within one year	false

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Stock-based Compensation - Stock-based compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Stock-based Compensation
Stock-based compensation expense	$ 5,485	$ 2,271
Research and development
Stock-based Compensation
Stock-based compensation expense	2,302	985
General and administrative
Stock-based Compensation
Stock-based compensation expense	$ 3,183	$ 1,286

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Common Stock - July Public Offering (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
	Jul. 03, 2025	Mar. 31, 2026	Mar. 31, 2025
Common Stock
Exercise of stock options (in shares)		31,195
Pre-funded warrants, exercise price per warrants (in dollar per warrant)		$ 0.0001	$ 0.0001
Exercise of pre-funded warrants (in shares)		400,000
Pre-funded warrants
Common Stock
Maximum ownership beyond which pre-funded warrant holders cannot exercise their rights (%)	19.99%
Notice period, for increase or decrease of specified percentage of warrant exercises	61 days
Common stock ownership \| Minimum \| Pre-funded warrants
Common Stock
Ownership percentage limit	4.99%
Common stock ownership \| Maximum \| Pre-funded warrants
Common Stock
Ownership percentage limit	9.99%
Combined voting power \| Minimum \| Pre-funded warrants
Common Stock
Ownership percentage limit	4.99%
Combined voting power \| Maximum \| Pre-funded warrants
Common Stock
Ownership percentage limit	9.99%
Underwritten public offering
Common Stock
Issuance of common stock, net of issuance costs (in shares)	3,059,615
Exercise of stock options (in shares)	576,923
Share price (in dollars per share)	$ 19.5
Proceeds from issuance of stock, net of expenses	$ 80.5
Underwritten public offering \| Pre-funded warrants
Common Stock
Issuance of common stock, net of issuance costs (in shares)	1,363,469
Share price (in dollars per share)	$ 19.4999
Pre-funded warrants, exercise price per warrants (in dollar per warrant)	$ 0.0001

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2026
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arr Modified	false
Non-Rule 10b5-1 Arr Modified	false

Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Accrued Expenses
Research and development	$ 14,124	$ 13,142
Professional fees	81	292
Compensation and related expenses	1,925	6,545
Other accrued expenses	39	18
Total	$ 16,169	$ 19,997

Background

3 Months Ended

Mar. 31, 2026

Background

Background

(1)	Background

ArriVent BioPharma, Inc., a Delaware corporation (the “Company”), founded on April 14, 2021, is a clinical-stage biopharmaceutical company focused on identifying, licensing and globalizing top biopharma innovations from around the world to deliver important medicines to patients. In June 2021, the Company entered into a license agreement with Shanghai Allist Pharmaceuticals Co. Ltd. (“Allist”) which granted the Company an exclusive license under certain intellectual property owned or controlled by Allist to develop, manufacture and commercialize any product containing firmonertinib or any of its derivatives as an active ingredient, for all uses, in all countries and territories other than greater China, which includes mainland China, Hong Kong, Macau and Taiwan (“Greater China”) (See Note 8). The Company’s lead development candidate, firmonertinib, is a third-generation tyrosine kinase inhibitor currently being evaluated in multiple clinical trials across a range of epidermal growth factor receptor mutations in non-small cell lung cancer, many for which there are limited treatment options.

Segment Information

3 Months Ended

Mar. 31, 2026

Segment Information

Segment Information

(9)	Segment Information

Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources in assessing performance. The Company has one reportable and operating segment: life science. The life science segment is engaged in identifying, licensing and globalizing top biopharma innovations from around the world to deliver important medicines to patients. The Company’s chief operating decision maker (“CODM”) is the chief executive officer.

The accounting policies of the life science segment are the same as those described in the summary of significant accounting policies. The CODM assesses performance for the life science segment based on net loss, which is reported on the condensed statement of operations and comprehensive loss. The measure of segment assets is reported on the balance sheet as total assets. All of the Company’s assets are located in the United States.

To date, the Company has not generated any product revenue. The Company expects to continue to incur significant expenses and operating losses for the foreseeable future as it advances product candidates through all stages of development and clinical trials and, ultimately, seek regulatory approval.

As such, the CODM uses cash forecast models in deciding how to invest into the life science segment. Such cash forecast models are reviewed to assess the entity-wide operating results and performance. Net loss is used to monitor budget versus actual results. Monitoring budgeted versus actual results is used in assessing performance of the segment, establishing cash forecast models and to optimize the distribution of resources across functions, therapeutic areas and research and development programs.

The table below summarizes the significant expense categories regularly provided to the CODM for the three months ended March 31, 2026 and 2025:


			Three Months Ended
	March 31,
(in thousands)	2026			2025
Operating expenses:
Research and development: Firmonertinib (excluding personnel-related and other internal costs):
FURTHER	$	1,738		$	2,595
FURVENT		9,131			9,445
FAVOUR		331			2
Other Firmonertinib costs		3,883			2,262
Total Firmonertinib		15,083			14,304
Research and development: Early-stage programs		12,307			40,981
Research and development: Personnel-related and other internal costs		10,227			6,005
General and administrative: Personnel-related costs		6,183			3,331
General and administrative: Other costs		2,311			2,151
Other segment items (a)		(2,791)			(2,385)
Net loss	$	43,320		$	64,387

(a) Other segment items consists of interest and investment income.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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Reference 25: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-41

+ Details

Summary of Significant Accounting Policies - Potentially dilutive securities (Details) - shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Employee Stock Option
Antidilutive securities
Potentially dilutive securities have been excluded from the computation of diluted weighted-average shares	7,220,584	4,059,300

Stock-based Compensation - Fair value (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Unrecognized compensation cost
Unrecognized compensation cost for awards (in dollars)	$ 82.0
Expected period to be recognized	3 years 2 months 8 days
Employee Stock Option
Fair value assumptions
Risk-free interest rate, minimum (as a percent)	3.72%	4.02%
Risk-free interest rate, maximum (as a percent)	3.94%	4.37%
Expected term	6 years 1 month 6 days
Expected volatility (as a percent)	87.30%
Expected volatility, minimum (as a percent)		98.30%
Employee Stock Option \| Minimum
Fair value assumptions
Expected term		6 years 1 month 6 days
Estimated fair value of the Company's common stock per share (in dollars per share)	$ 20.8	$ 22.03
Employee Stock Option \| Maximum
Fair value assumptions
Estimated fair value of the Company's common stock per share (in dollars per share)	$ 24.31	$ 27.56

Common Stock - At the Market Offering (Details) - 2025 WKSI Shelf - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Feb. 03, 2025
Common Stock
Maximum amount authorized to be sold in offering		$ 250.0
Issuance of common stock, net of issuance costs (in shares)	2,425,495
Proceeds from issuance of stock, net of expenses	$ 54.7
Amount of common stock remaining authorized for future issuance	$ 66.9

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Segment Information (Tables)

3 Months Ended

Mar. 31, 2026

Segment Information

Schedule of significant expense categories

The table below summarizes the significant expense categories regularly provided to the CODM for the three months ended March 31, 2026 and 2025:


			Three Months Ended
	March 31,
(in thousands)	2026			2025
Operating expenses:
Research and development: Firmonertinib (excluding personnel-related and other internal costs):
FURTHER	$	1,738		$	2,595
FURVENT		9,131			9,445
FAVOUR		331			2
Other Firmonertinib costs		3,883			2,262
Total Firmonertinib		15,083			14,304
Research and development: Early-stage programs		12,307			40,981
Research and development: Personnel-related and other internal costs		10,227			6,005
General and administrative: Personnel-related costs		6,183			3,331
General and administrative: Other costs		2,311			2,151
Other segment items (a)		(2,791)			(2,385)
Net loss	$	43,320		$	64,387

(a) Other segment items consists of interest and investment income.

CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	Mar. 31, 2026	Mar. 31, 2025
Cash flows from operating activities:
Net loss	$ (43,320)	$ (64,387)
Adjustment to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	5,485	2,271
Amortization/Accretion of bond discounts/premiums	(559)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(2,561)	(1,591)
Other assets	37
Accounts payable	2,807	582
Accrued expenses	(3,828)	(4,879)
Operating lease liabilities	47	(4)
Net cash used in operating activities	(41,892)	(68,008)
Cash flows from investing activities:
Purchase of short-term and long-term investments	(64,383)	(9,817)
Sales and maturities of short-term and long-term investments	67,965	46,638
Net cash used in investing activities	3,582	36,821
Cash flows from financing activities:
Proceeds from issuance of common stock, net of issuance costs	54,724	6,516
Proceeds from the exercise of stock options	149	293
Payment of deferred financing costs		(50)
Net cash provided by financing activities	54,873	6,759
Net increase (decrease) in cash and cash equivalents	16,563	(24,428)
Cash and cash equivalents at beginning of the year	45,540	74,293
Cash and cash equivalents at end of the year	$ 62,103	$ 49,865

Stock-based Compensation - Plans (Details) - shares	1 Months Ended	3 Months Ended
Stock-based Compensation - Plans (Details) - shares	Jan. 31, 2024	Mar. 31, 2026	Dec. 31, 2022	Jun. 30, 2021
2021 Plan
Stock-based Compensation
Shares authorized			2,748,818	803,564
2024 Plan
Stock-based Compensation
Additional shares authorized	3,900,000
Shares available for grant		2,704,257
Employee Stock Option
Stock-based Compensation
Vesting Period		4 years

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Summary of Significant Accounting Policies - Net loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Numerator:
Net loss (basic)	$ (43,320)	$ (64,387)
Net loss (diluted)	$ (43,320)	$ (64,387)
Denominator:
Weighted-average shares of common stock outstanding	43,755,706
Weighted-average pre-funded warrants outstanding	1,311,952
Weighted-average shares of common stock outstanding, basic (in shares)	45,067,658	33,898,870
Weighted-average shares of common stock outstanding, diluted (in shares)	45,067,658	33,898,870
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.96)	$ (1.9)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	(0.96)	(1.9)
Pre-funded warrants, exercise price per warrants (in dollar per warrant)	$ 0.0001	$ 0.0001

Stock-based Compensation

3 Months Ended

Mar. 31, 2026

Stock-based Compensation

Stock-based Compensation

(7)	Stock-based Compensation

In June 2021, the Company adopted the 2021 Employee, Director and Consultant Equity Incentive Plan, as amended (the “2021 Plan”), that authorized the Company to grant up to 803,564 shares of common stock via stock-based compensation awards. In 2022, the Company amended the 2021 Plan and increased the total number of shares authorized under the 2021 Plan to 2,748,818. In January 2024, the Company adopted the 2024 Employee, Director and Consultant Equity Incentive Plan (the “2024 Plan”) that authorized the Company to grant up to 3,900,000 shares of common stock plus any remaining ungranted or forfeited shares from the 2021 Plan. As of March 31, 2026, there were 2,704,257 shares available to be granted under the 2024 Plan. The Company’s stock options vest based on the terms in the awards agreements and generally vest over four years. The Company recorded stock-based compensation expense in the following expense categories in its accompanying statements of operations and comprehensive loss (in thousands):


	Three Months Ended
	March 31,
	2026		2025
Research and development	$	2,302	$	985
General and administrative		3,183		1,286
	$	5,485	$	2,271

The following is a summary of stock options activity:


				Weighted
		Weighted		average
		average		remaining	Aggregate
		exercise		contractual	Intrinsic Value
	Options	price		term (years)	(in thousands)
Outstanding as of December 31, 2025	4,328,880	$	15.56
Granted	2,950,250		22.62
Exercised	(31,195)		5.15
Forfeited/Expired	(27,351)		9.46
Outstanding as of March 31, 2026	7,220,584		18.48	8.68	$	40,051
Exercisable as of March 31, 2026	1,986,886		9.95	7.09		27,924
Vested and expected to vest at March 31, 2026	7,220,584	$	18.48	8.68	$	40,051

The weighted-average grant-date fair value of options granted in the first three months of 2026 and 2025 were $16.98 and $22.04 per share, respectively. The fair value was estimated using the Black-Scholes option-pricing model based on the following assumptions:


	Three Months Ended
	March 31,
	2026		2025
Risk-free interest rate		3.72% - 3.94%		4.02% - 4.37%
Expected term		6.1 years		6.1 years
Expected volatility		87.3%		98.3%
Expected dividend yield		—		—
Estimated fair value of the Company's common stock per share	$	20.80 - 24.31	$	22.03 - 27.56

Unrecognized compensation cost for awards not vested as of March 31, 2026 was $82.0 million and will be expensed over a weighted-average period of 3.19 years.

Development Stage Risks and Liquidity

3 Months Ended

Mar. 31, 2026

Development Stage Risks and Liquidity

Development Stage Risks and Liquidity

(2)	Development Stage Risks and Liquidity

The Company has incurred losses since inception and has an accumulated deficit of $448.0 million as of March 31, 2026. The Company has concluded that the aggregate balance of cash and cash equivalents and marketable securities of $326.4 million as of March 31, 2026 are sufficient to sustain planned operations through at least twelve months from the issuance date of these financial statements.

The Company anticipates incurring additional losses until such time, if ever, that it can generate significant sales from its product candidates currently in development; as a result, additional capital will be needed to fund its future operating and capital requirements. There can be no assurance that the Company will be able to raise sufficient additional capital on acceptable terms, if at all. If such additional financing is not available on satisfactory terms, or is not available in sufficient amounts, the Company’s financial condition or results of operations may be materially adversely affected.

The Company is subject to those risks associated with any specialty biotechnology company that has substantial expenditures for research and development. In addition, geopolitical tensions, volatility of capital markets, and other adverse macroeconomic events, including those due to inflationary pressures, changing interest rates, bank instability and the ability of the U.S. government to manage federal debt limits, as well as the potential impact of other health crises on the global financial markets, may reduce the Company's ability to access capital, which could negatively affect its liquidity.

CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Operating expenses:
Research and development	$ 37,617	$ 61,289
General and administrative	8,494	5,483
Total operating expenses	46,111	66,772
Operating loss	(46,111)	(66,772)
Interest and investment income	2,791	2,385
Net loss	(43,320)	(64,387)
Unrealized gain (loss) on marketable securities	(284)	194
Total other comprehensive gain (loss)	(284)	194
Total comprehensive loss	$ (43,604)	$ (64,193)
Share information:
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.96)	$ (1.9)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.96)	$ (1.9)
Weighted-average shares of common stock outstanding, basic (in shares)	45,067,658	33,898,870
Weighted-average shares of common stock outstanding, diluted (in shares)	45,067,658	33,898,870

Common Stock

3 Months Ended

Mar. 31, 2026

Common Stock

Common Stock

(10)	Common Stock

“At-the-Market” Offering

On February 3, 2025, the Company filed an automatic shelf registration statement on Form S-3ASR with the SEC pursuant to which the Company registered for sale an indeterminate amount of any combination of its common stock, preferred stock, debt securities, warrants, rights and/or units from time to time and at prices and on terms that the Company may determine, which is referred to as the “2025 WKSI Shelf”. The 2025 WKSI Shelf includes a prospectus covering up to an aggregate of $250.0 million of shares of common stock that the Company is able to issue and sell from time to time, through Jefferies LLC (“Jefferies”), acting as its sales agent, pursuant to the Open Market Sale Agreement^SM, dated February 3, 2025 (the “Sales Agreement”), for its “at-the-market” equity program.

Under the Sales Agreement, Jefferies may sell shares of the Company’s common stock by any method permitted by law deemed to be an “at-the-market” offering as defined in Rule 415 of the Securities Act of 1933, as amended, subject to the terms of the Sales Agreement.

During the three months ended March 31, 2026, the Company sold 2,425,495 shares of common stock pursuant to the Sales Agreement for total proceeds of $54.7 million, net of commissions. As of March 31, 2026, the Company has approximately $66.9 million remaining for future issuances of common stock pursuant to the Sales Agreement.

July 2025 Public Offering

On July 3, 2025, the Company closed an underwritten public offering in which the Company issued and sold an aggregate of 3,059,615 shares of its common stock, including the exercise in full of the underwriters’ option to purchase 576,923 additional shares of common stock, at a public offering price of $19.50 per share, and, in lieu of shares of common stock to certain investors, pre-funded warrants to purchase up to 1,363,469 shares of common stock at a public offering price of $19.4999 per pre-funded warrant, which represents the per share public offering price for the shares less the $0.0001 per share exercise price for each pre-funded warrant. The pre-funded warrants were recorded as a component of shareholders’ equity within additional paid-in-capital and have no expiration date. As of March 31, 2026, 400,000 of the pre-funded warrants have been exercised. The proceeds to the Company of this July 2025 offering, net of underwriting discounts, commissions, and other expenses were $80.5 million.

The pre-funded warrants are exercisable at any time after their original issuance. A holder of pre-funded warrants may not exercise the pre-funded warrant if the holder, together with its affiliates, would beneficially own more than 4.99%, or, at the election of such holder upon issuance, 9.99%, of the number of shares of common stock outstanding or more than 4.99%, or, at the election of such holder upon issuance, 9.99%, of the combined voting power of the Company’s securities outstanding immediately after giving effect to such exercise. A holder of pre-funded warrants may increase or decrease this percentage to any other percentage not exceeding 19.99%, in the case of an increase, upon 61 days’ prior notice to the Company.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

Commitments, Contingencies, and Collaborations

3 Months Ended

Mar. 31, 2026

Commitments, Contingencies, and Collaborations

Commitments, Contingencies, and Collaborations

(8)	Commitments, Contingencies, and Collaborations

The Company entered into various license and collaboration agreements under which it is obligated to make contingent payments as described below.

Allist

In June 2021, the Company entered into a Global Technology Transfer and License Agreement with Allist (“Allist Agreement”). Pursuant to the Allist Agreement, the Company was granted an exclusive license under certain intellectual property to develop, manufacture and commercialize certain licensed products in the field in the licensed territory. Upon execution of the Allist Agreement, the Company paid Allist a non-refundable cash payment of $40.0 million and issued 1,276,250 shares of its common stock. The upfront payment and the fair value of the common stock issued was recorded to research and development expense in 2021.

Upon the achievement of certain clinical, regulatory and commercial milestones using the licensed technology, the Company is obligated to make future milestone payments to Allist of up to $105.0 million in clinical and regulatory milestones and up to $655.0 million in commercial milestones. Furthermore, royalties, ranging from high single digit to low mid-teen percentages will be payable to Allist on net sales of licensed products in licensed territories.

In connection with the Allist Agreement, in December 2021, the parties also entered into a Joint Clinical Collaboration Agreement (“Clinical Collaboration”) to define the framework under which the parties will cooperate and share costs related to global clinical studies to be conducted jointly by the Company and Allist. During the three months ended March 31, 2026 and 2025, the Company incurred $0.7 million and $0.5 million, respectively, in cost reimbursements to Allist under the Clinical Collaboration which have been recorded as research and development expense. The Company also received cost reimbursements from Allist of $0.3 and $0.4 million for the three months ended March 31, 2026 and 2025, respectively, which have been recorded as a reduction of research and development expenses. The Company incurred $5.0 million in clinical milestone payments to Allist during the year ended December 31, 2025. Through March 31, 2026, no additional milestones were met or achieved or were probable of achievement.

Alphamab

In June 2024, the Company entered into a collaboration agreement with Jiangsu Alphamab Biopharmaceuticals Co., Ltd. (“Alphamab”) to discover, develop and commercialize novel antibody drug conjugates (“ADCs”) for the treatment of cancers (“Alphamab Agreement”).

Under the Alphamab Agreement, both companies seek to leverage Alphamab’s proprietary linker-payload platform and glycan-conjugation technology to identify novel ADCs for oncology indications. The Alphamab Agreement gives the Company exclusive rights to develop and commercialize ADCs globally, except Greater China, where Alphamab retains the right to develop and commercialize the ADCs.

The terms of the Alphamab Agreement include combined upfront and potential milestone payments to Alphamab of up to $201.5 million based on the achievement of certain regulatory and development milestones, and up to $414.0 million based on the achievement of certain commercial milestones. In addition, Alphamab is entitled to receive tiered sales royalties, ranging from low single digit to mid-single digit percentages, from the Company for net sales of each ADC product.

The upfront payment was recorded to research and development expense during the three-month period ended June 30, 2024. During the three months ended March 31, 2025, the Company paid $0.1 million in cost reimbursements to Alphamab under the Alphamab Agreement which have been recorded as research and development expense. Finally, during the year ended December 31, 2025, the Company paid $1.2 million upon the approval of a target pair selection which was also included in research and development expense. No such expenses were incurred in the three months ended March 31, 2026. Through March 31, 2026, no further milestones have been met or achieved, or are probable of achievement, since the inception of the agreement.

Aarvik

In December 2021, the Company entered into a Research Collaboration Agreement, as amended, effective June 30, 2023 (the “Aarvik Collaboration Agreement”), with Aarvik Pharmaceuticals, Inc. (“Aarvik”), under which the Company is required to pay Aarvik up to $3.1 million on statements of work (“SOWs”) and an initiation fee of $0.3 million. After the completion of the SOWs, the Company has an exclusive option to license the Aarvik intellectual property, and the option to acquire certain of Aarvik’s intellectual property, after which it is the Company’s sole responsibility to research, develop, manufacture and commercialize any applicable compound and product in the field and territory. In August 2024, the Company paid $1.0 million to exercise that option, and as a result is now obligated to pay up to $18.0 million per product upon the achievement of certain clinical and regulatory milestone events and up to $80.0 million per product in commercial milestones. Additionally, the Company is obligated to pay Aarvik royalties in the mid-single digits based on net sales of licensed products.

On August 9, 2024, the Company entered into an amendment and restatement of the Aarvik Collaboration Agreement, as amended on July 2, 2025 (the “Amended and Restated Aarvik Collaboration Agreement”). Under the Amended and Restated Aarvik Collaboration Agreement, Aarvik granted the Company an exclusive option to obtain exclusive rights to certain of Aarvik’s intellectual property for the research, development, manufacture, use, commercialization, or other exploitation of the ADCs related to (i) the two agreed targets to which the compounds being developed under the collaboration bind, and (ii) the acquisition of exclusive rights to certain intellectual property generated during the collaboration. ARR-002, a novel tetravalent MUC16/NaPi2b targeting ADC, was discovered through the collaboration with Aarvik. ArriVent recently announced US IND clearance for ARR-002 and its expectation to initiate a Phase 1 trial and dose a first patient in the second half 2026.

From inception to date, under the Amended and Restated Aarvik Collaboration Agreement, the Company has paid Aarvik a collaboration initiation fee and research fees as provided in the SOWs in an aggregate amount of $5.4 million.

The Company incurred $0.1 million in research and development expenses related to the Aarvik SOWs during the three months ended March 31, 2025. No such expenses were incurred during the three months ended March 31, 2026. No milestones have been met or achieved, or are probable of achievement, since the inception of the Aarvik Collaboration Agreement.

Lepu

On January 21, 2025, the Company entered into an Exclusive License Agreement (the “Lepu Biopharma Agreement”) with Lepu Biopharma Co., Ltd. (“Lepu”), pursuant to which Lepu granted the Company a right to develop and commercialize ARR-217, an antibody drug conjugate for gastrointestinal cancers outside Greater China.

Under the Lepu Biopharma Agreement, Lepu granted to the Company: (i) an exclusive, royalty-bearing, sublicensable license under certain intellectual property owned or controlled by Lepu, to develop, manufacture and commercialize any product containing ARR-217 for all uses in all countries and territories other than Greater China (the “ArriVent Territory”); and (ii) a non-exclusive license under certain intellectual property controlled by Lepu to develop, manufacture and commercialize any product containing ARR-217 for use in oncology in the ArriVent Territory. Under the Lepu Biopharma Agreement, the Company paid Lepu a one-time upfront payment of $40 million and, during the three months ended June 30, 2025, the Company paid $1.0 million to Lepu for the achievement of the first developmental milestone under the Lepu Biopharma Agreement as it became probable of achievement during the second quarter. The upfront payment was included in research and development expenses. Finally, Lepu is eligible to receive payments of up to $0.3 billion in development and regulatory milestones, and up to $0.89 billion in commercial milestones, and tiered royalties in high single-digit to low-teen percentages on net sales in the ArriVent Territory.

During the three months ended March 31, 2026, Lepu earned a $6.0 million developmental milestone payment. No milestones have been met or achieved, or are probable of achievement, subsequent to the developmental milestone noted above. During three months ended March 31, 2026, the Company incurred an additional $0.8 million in research and development expenses related to the Lepu Biopharma Agreement. No such expenses were incurred during the three months ended March 31, 2025.

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Mar. 31, 2026	Mar. 31, 2025
Pay vs Performance Disclosure
Net Income (Loss)	$ (43,320)	$ (64,387)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2026

Summary of Significant Accounting Policies

Summary of Significant Accounting Policies

(3)	Summary of Significant Accounting Policies

The summary of significant accounting policies included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025, filed with the Securities and Exchange Commission on March 5, 2026 (the “Annual Report”) has not materially changed.

(a)	Interim Financial Statements

(b)	Use of Estimates

(c)	Fair Value Measurements

•

Level 1 Inputs: Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date.

•

(d)	Net Loss per Share

The following table sets forth the computation of net loss per share, basic and diluted (in thousands, except share and per share data):


	Three Months Ended
	March 31,
	2026		2025
Numerator:
Net loss	$	(43,320)	$	(64,387)
Denominator:
Weighted-average shares of common stock outstanding		43,755,706		—
Weighted-average pre-funded warrants outstanding (1)		1,311,952		—
Weighted-average shares of common stock outstanding, basic and diluted		45,067,658		33,898,870

Net loss per share attributable to common stockholders, basic and diluted	$	(0.96)	$	(1.90)

(e)	Accounting Pronouncements Not Yet Adopted

(f) License and Collaboration Agreements

(g) Other Comprehensive Income (Loss)

Accrued Expenses (Tables)

3 Months Ended

Mar. 31, 2026

Accrued Expenses

Schedule of accrued expenses

Accrued expenses consisted of the following (in thousands):


	March 31,		December 31,
	2026		2025
Research and development	$	14,124	$	13,142
Professional fees		81		292
Compensation and related expenses		1,925		6,545
Other accrued expenses		39		18
	$	16,169	$	19,997

Accrued Expenses

3 Months Ended

Mar. 31, 2026

Accrued Expenses

Accrued Expenses

(6)	Accrued Expenses

Accrued expenses consisted of the following (in thousands):


	March 31,		December 31,
	2026		2025
Research and development	$	14,124	$	13,142
Professional fees		81		292
Compensation and related expenses		1,925		6,545
Other accrued expenses		39		18
	$	16,169	$	19,997

Segment Information (Details) $ in Thousands	3 Months Ended
Segment Information (Details) $ in Thousands	Mar. 31, 2026 USD ($) segment	Mar. 31, 2025 USD ($)
Operating expenses:
Number of reportable segments \| segment	1
Total Firmonertinib	$ 37,617	$ 61,289
Net loss	43,320	64,387
Life science
Operating expenses:
Research and development: Early-stage programs	12,307	40,981
Research and development: Personnel-related and other internal costs	10,227	6,005
General and administrative: Personnel-related costs	6,183	3,331
General and administrative: Other costs	2,311	2,151
Other segment items	(2,791)	(2,385)
Net loss	$ 43,320	$ 64,387
Description of other segment item	Other segment items consists of interest and investment income.	Other segment items consists of interest and investment income.
Life science \| Firmonertinib
Operating expenses:
Other Firmonertinib costs	$ 3,883	$ 2,262
Total Firmonertinib	15,083	14,304
Life science \| Further
Operating expenses:
Research and development: Firmonertinib (excluding personnel-related and other internal costs):	1,738	2,595
Life science \| Furvent
Operating expenses:
Research and development: Firmonertinib (excluding personnel-related and other internal costs):	9,131	9,445
Life science \| Favour
Operating expenses:
Research and development: Firmonertinib (excluding personnel-related and other internal costs):	$ 331	$ 2

Commitments, Contingencies, and Collaborations - Alphamab (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Jun. 30, 2024
Agreement
Research and development	$ 37,617	$ 61,289
Collaborative Agreement \| Alphamab
Agreement
Maximum amount payable upon achievement of development and regulatory milestones				$ 201,500
Maximum amount payable upon achievement of commercial milestones				$ 414,000
Research and development expense, cost reimbursements		$ 100
Research and development expense, approval of a target pair selection			$ 1,200
Research and development	$ 0

Debt (Details) - Loan and security agreement, Silicon Valley Bank - USD ($) $ in Thousands	May 08, 2025	Mar. 31, 2026
Debt
Term loan amounts have been drawn		$ 0
Interest rate (%)	6.00%
Basis spread on variable rate (%)	0.75%
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	us-gaap:PrimeRateMember
Term Loan
Debt
Maximum borrowing capacity	$ 75,000
First tranche. Term Loan
Debt
Maximum borrowing capacity	35,000
Second tranche. Term Loan
Debt
Maximum borrowing capacity	15,000
Third tranche. Term Loan
Debt
Maximum borrowing capacity	$ 25,000

Fair Value Measurements

3 Months Ended

Mar. 31, 2026

Fair Value Measurements

Fair Value Measurements

(4)	Fair Value Measurements


	March 31, 2026
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Level 1		Level 2		Level 3

Money market funds	$	40,127	$	—	$	—	$	40,127	$	40,127	$	—	$	—
Corporate securities		110,131		16		(124)		110,023		26,831		83,192		—
Government securities		154,419		28		(192)		154,255		—		154,255		—
Total assets measured at fair value	$	304,677	$	44	$	(316)	$	304,405	$	66,958	$	237,447	$	—


	December 31, 2025
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Level 1		Level 2		Level 3

Money market funds	$	40,494	$	—	$	—	$	40,494	$	40,494	$	—	$	—
Corporate securities		105,373		78		(25)		105,426		16,347		89,079		—
Government securities		161,882		116		(143)		161,855		—		161,855		—
Total assets measured at fair value		307,749		194		(168)	$	307,775	$	56,841	$	250,934	$	—

Cash balances were $21.9 million and $5.0 million at March 31, 2026 and December 31, 2025, respectively. Money market funds are highly liquid investments. The pricing information on the Company’s money market fund is based on quoted prices in active markets. This approach results in a classification of these securities as Level 1 of the fair value hierarchy.

The Company’s investment portfolio includes many fixed income securities that do not always trade on a daily basis. As a result, the pricing services used by the Company applied other available information as applicable through processes such as benchmark yields, benchmarking of like securities, sector groupings and matrix pricing to prepare evaluations. In addition, model processes were used to assess interest rate impact and develop prepayment scenarios. These models take into consideration relevant credit information, perceived market movements, sector news and economic events. The inputs into these models may include benchmark yields, reported trades, broker-dealer quotes, issuer spreads and other relevant data.

As of March 31, 2026, $264.3 million of the Company’s fixed income securities have maturity dates within the next twelve months. All securities are considered available for sale.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
-SubTopic 820
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2026

Summary of Significant Accounting Policies

Schedule of computation of net loss per share, basic and diluted

The following table sets forth the computation of net loss per share, basic and diluted (in thousands, except share and per share data):


	Three Months Ended
	March 31,
	2026		2025
Numerator:
Net loss	$	(43,320)	$	(64,387)
Denominator:
Weighted-average shares of common stock outstanding		43,755,706		—
Weighted-average pre-funded warrants outstanding (1)		1,311,952		—
Weighted-average shares of common stock outstanding, basic and diluted		45,067,658		33,898,870

Net loss per share attributable to common stockholders, basic and diluted	$	(0.96)	$	(1.90)

Prepaid Expenses and Other Current Assets

3 Months Ended

Mar. 31, 2026

Prepaid Expenses and Other Current Assets

Prepaid Expenses and Other Current Assets

(5)	Prepaid Expenses and Other Current Assets

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


	March 31,		December 31,
	2026		2025
Research and development	$	20,828	$	19,830
Professional fees		480		3
Insurance		952		183
Other		60		60
	$	22,320	$	20,076

Commitments, Contingencies, and Collaborations - Allist (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Jun. 30, 2021	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Agreement
Research and development		$ 37,617	$ 61,289
Global Technology Transfer And License Agreement \| Allist
Agreement
Cash payment	$ 40,000
Maximum amount payable upon achievement of certain clinical and regulatory milestone events		105,000
Maximum amount payable upon achievement of commercial milestones		655,000
Global Technology Transfer And License Agreement \| Allist \| Common stock
Agreement
Shares issued in execution of agreement (in shares)	1,276,250
Clinical Collaboration Agreement \| Allist
Agreement
Research and development		700	500
Cost reimbursement		$ 300	$ 400
Milestone payments paid				$ 5,000

CONDENSED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2026	Dec. 31, 2025
CONDENSED BALANCE SHEETS
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	45,308,941	42,452,251
Common stock, shares outstanding (in shares)	45,308,941	42,452,251

Stock-based Compensation (Tables)

3 Months Ended

Mar. 31, 2026

Stock-based Compensation

Schedule of stock-based compensation expense


	Three Months Ended
	March 31,
	2026		2025
Research and development	$	2,302	$	985
General and administrative		3,183		1,286
	$	5,485	$	2,271

Schedule of of stock options activity under the plan


				Weighted
		Weighted		average
		average		remaining	Aggregate
		exercise		contractual	Intrinsic Value
	Options	price		term (years)	(in thousands)
Outstanding as of December 31, 2025	4,328,880	$	15.56
Granted	2,950,250		22.62
Exercised	(31,195)		5.15
Forfeited/Expired	(27,351)		9.46
Outstanding as of March 31, 2026	7,220,584		18.48	8.68	$	40,051
Exercisable as of March 31, 2026	1,986,886		9.95	7.09		27,924
Vested and expected to vest at March 31, 2026	7,220,584	$	18.48	8.68	$	40,051

Schedule of assumptions used in estimating the fair value of options


	Three Months Ended
	March 31,
	2026		2025
Risk-free interest rate		3.72% - 3.94%		4.02% - 4.37%
Expected term		6.1 years		6.1 years
Expected volatility		87.3%		98.3%
Expected dividend yield		—		—
Estimated fair value of the Company's common stock per share	$	20.80 - 24.31	$	22.03 - 27.56

Prepaid Expenses and Other Current Assets (Tables)

3 Months Ended

Mar. 31, 2026

Prepaid Expenses and Other Current Assets

Schedule of prepaid expenses and other current assets

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


	March 31,		December 31,
	2026		2025
Research and development	$	20,828	$	19,830
Professional fees		480		3
Insurance		952		183
Other		60		60
	$	22,320	$	20,076

CONDENSED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
CONDENSED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT)
Issuance costs	$ 2,418	$ 858