0001628280-26-033669 | 10-Q | XBRL Viewer

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Long-Term Debt - Schedule of Long Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Debt Disclosure [Abstract]
Interest Rate	3.25%
Total	$ 0.5	$ 0.6
Less: current installments included within Accounts payable and accrued liabilities	(0.2)	(0.2)
Total long-term debt	$ 0.3	$ 0.4

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

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+ Details

Research Collaboration and License Agreements

3 Months Ended

Mar. 31, 2026

Research Collaboration And License Agreements [Abstract]

Research Collaboration and License Agreements

Vepdegestrant (ARV-471) Collaboration Agreement

In July 2021, the Company entered into a Collaboration Agreement with Pfizer Inc. (“Pfizer”) (the “Vepdegestrant (ARV-471) Collaboration Agreement”) pursuant to which the Company granted Pfizer worldwide co-exclusive rights to develop and commercialize products containing the Company’s proprietary compound vepdegestrant (the “Licensed Products”). Under the Vepdegestrant (ARV-471) Collaboration Agreement, the Company received an upfront, non-refundable payment of $650.0 million. In addition, the Company is eligible to receive up to an additional $1.4 billion in contingent payments based on specific regulatory and sales-based milestones for the Licensed Products. Of the total contingent payments, $400.0 million in regulatory milestones are related to marketing approvals and $1.0 billion are related to sales-based milestones. There were no regulatory or sales-based milestone payments received through March 31, 2026.

The Company and Pfizer share equally all development costs for the Licensed Products, including costs of conducting clinical trials, subject to certain exceptions.

The Company and Pfizer share equally all development costs for the Licensed Products, including costs of conducting clinical trials, subject to certain exceptions. Except for certain regions described below, the parties will also share equally all profits and losses in commercialization and medical affairs activities for the Licensed Products in all other countries, subject to certain exceptions.

As a direct result of the Company’s entry into the Vepdegestrant (ARV-471) Collaboration Agreement, the Company incurred direct and incremental costs to obtain the contract, paid to a financial advisor, totaling $12.9 million. In accordance with Accounting Standards Codification ("ASC") 340, Other Assets and Deferred Costs, the Company recognized an asset of $12.9 million in collaboration contract asset and other assets in the condensed consolidated balance sheet at inception of the Vepdegestrant (ARV-471) Collaboration Agreement, which is being amortized as general and administrative expense over the total estimated period of performance under the Vepdegestrant (ARV-471) Collaboration Agreement.

In the second quarter of 2026, the Company announced that the U.S. Food and Drug Administration ("FDA") has granted approval for VEPPANU™ (vepdegestrant) for the treatment of adults with estrogen receptor-positive (“ER+”)/human epidermal growth factor receptor 2-negative (“HER2-”), estrogen receptor 1 (“ESR1”)-mutated advanced or metastatic breast cancer, as detected by an FDA-authorized test, with disease progression following at least one line of endrocrine-based therapy.

Pursuant to the Vepdegestrant (ARV-471) Collaboration Agreement, the Company will receive $50.0 million as a development milestone payment in connection with the FDA’s approval of VEPPANU (the “Milestone Payment”). The Milestone Payment will be offset by certain amounts that the Company will owe to Yale University ("Yale") pursuant to the amended and restated license agreement, dated June 18, 2024, by and between the Company, one of its subsidiaries, and Yale (the "Yale Agreement").

In September 2025, the Company announced that the Company and Pfizer have agreed to jointly select a third party for the commercialization and potential further development of vepdegestrant. The Company and its collaborator, Pfizer Inc., remain on track to announce selection of a third party to commercialize VEPPANU.

Pfizer Research Collaboration Agreement

In December 2017, the Company entered into a Research Collaboration and License Agreement with Pfizer (the “Pfizer Research Collaboration Agreement”). Under the terms of the Pfizer Research Collaboration Agreement, the Company received an upfront, non-refundable payment and certain additional payments totaling $28.0 million in 2018 in exchange for use of the Company’s technology license and to fund Pfizer-related research as defined within the Pfizer Research Collaboration Agreement. These payments are being recognized over the total estimated period of performance. As of March 31, 2026, there remains a single target under the Pfizer Research Collaboration Agreement, and, in accordance with the terms of such Agreement, the Company is eligible to receive up to an additional $3.8 million in non-refundable option payments if Pfizer exercises its option for such target protein under the Pfizer Research Collaboration Agreement.

The Company is also entitled to receive up to $225.0 million in development milestone payments and up to $550.0 million in sales-based milestone payments for all designated target proteins under the Pfizer Research Collaboration Agreement, as well as tiered royalties based on sales, which may be subject to reductions. There were no sales-based milestone payments or royalties received through March 31, 2026.

Novartis License and Asset Agreements

In April 2024, the Company entered into a transaction (the "Novartis Transaction"), including both a license agreement (the "Novartis License Agreement") and an asset purchase agreement (the "Novartis Asset Agreement") with Novartis Pharma AG ("Novartis") for the worldwide development, manufacture and commercialization of luxdegalutamide (ARV-766), the Company's second generation PROTAC androgen receptor (AR) degrader for patients with prostate cancer and for the sale of the Company's preclinical AR-V7 program. Under the terms of the agreements, Novartis is responsible for worldwide clinical development and commercialization of luxdegalutamide (ARV-766) and has all research, development, manufacturing, and commercialization rights with respect to the Company’s PROTAC protein degrader targeting AR-V7, a splice variant of the AR.

In May 2024, Novartis paid to the Company a one-time, upfront payment in the aggregate amount of $150.0 million in accordance with the terms of the Novartis License Agreement and the Novartis Asset Agreement. The upfront payment was recognized as revenue over the performance period, which concluded as of December 31, 2024 as the technology transfer period ended as the Company completed the transition of its ongoing and planned clinical trials of luxdegalutamide (ARV-766) to Novartis.

Under the terms of the Novartis License Agreement, the Company is eligible to receive up to an additional $1.01 billion as contingent payments based on specified development, regulatory and commercial milestones for luxdegalutamide (ARV-766) being met, as well as tiered royalties based on worldwide net sales of luxdegalutamide (ARV-766), subject to reduction under certain circumstances as provided in the Novartis License Agreement. There were no development, regulatory or commercial milestone payments, or sales-based royalties received during the three months ended March 31, 2026 and 2025.

The Novartis License Agreement will continue on a country-by-country basis (or, in certain cases, a region-by-region basis) until the expiration of the applicable royalty term for such country (or region, as applicable). The Novartis License Agreement contains customary termination provisions, including that either party may terminate the Novartis License Agreement (a) upon the material breach of the other party or (b) in the event the other party experiences an insolvency event. Additionally, Novartis may terminate the Novartis License Agreement for convenience or upon a safety or regulatory issue.

Restated Genentech Agreement

In November 2017, the Company entered into an Amended and Restated Option, License, and Collaboration Agreement (the “Restated Genentech Agreement”) with Genentech, Inc. and F. Hoffman-La Roche Ltd. (together "Genentech"), amending a previous Genentech agreement entered into in September 2015. Under the Restated Genentech Agreement, the Company received additional upfront, non-refundable payments of $34.5 million (in addition to $11.0 million received under the previous agreement in 2015) to fund Genentech-related research. Upfront non-refundable payments were recognized as revenue over the performance period, which concluded during the first quarter of 2023. The research phase of the collaboration with Genentech has ended. As such, Genentech is no longer able to nominate new targets into the

collaboration. The only target that remains part of the collaboration is the PROTAC targeted protein degrader for which Genentech exercised its exclusive option upon amendment and restatement of the agreement.

The Company is eligible to receive up to $44.0 million per target protein in development milestone payments, $52.5 million in regulatory milestone payments and $60.0 million in commercial milestone payments based on sales as well as tiered royalties based on sales. There were no development, regulatory or commercial milestone payments or royalties received through March 31, 2026.

During the three months ended March 31, 2026 and 2025, the Company's sources of revenue were as follows:


(dollars in millions)	March 31, 2026		March 31, 2025
Revenue
Vepdegestrant (ARV-471) Collaboration Agreement	$	14.4	$	189.9
Pfizer Research Collaboration Agreement	1.2		(1.1)
Total Revenue	$	15.6	$	188.8

During the three months ended March 31, 2025, the Company updated its estimate to satisfy the performance obligations under the Vepdegestrant (ARV-471) Collaboration Agreement due to the removal of the first-line Phase 3 combination trial with Pfizer’s novel investigational CDK4 inhibitor, atirmociclib, and the removal of the second-line Phase 3 combination trial with a CDK4/6 inhibitor from the development plan. The change in accounting estimate resulted in an increase in revenue of $150.2 million, an increase in operating expenses of $2.6 million, a decrease in net loss of $147.6 million, and an increase in basic and diluted earnings per share of $2.04 and $2.03, respectively, for the three months ended March 31, 2025.

During the three months ended March 31, 2025, the Company also changed its estimate of the duration of the performance period under the Pfizer Research Collaboration Agreement as a result of updated research timelines. The change in accounting estimate resulted in a decrease in revenue and net income of $2.5 million , and a decrease in basic and diluted loss per share of $0.03 for the three months ended March 31, 2025. The reversed revenue will continue to be recognized in future periods as the Company continues to advance on the performance obligation under the updated collaboration timeline.

During the three months ended March 31, 2026, no changes in accounting estimates related to the Company's collaborations were recorded.

Changes in the Company's contract balances for the three months ended March 31, 2026 and 2025 were as follows:


(dollars in millions)	March 31, 2026		March 31, 2025
Accounts receivable related to collaborations
Beginning balance	$	1.0	$	5.7
Additions	0.8		—
Payments received	—		(5.3)
Ending balance	$	1.8	$	0.4
Accounts payable related to collaborations
Beginning balance	$	16.8	$	5.4
Additions	9.1		19.4
Payments made	—		(5.4)
Ending balance	$	25.9	$	19.4
Contract assets: Collaboration contract asset
Beginning balance	$	3.5	$	7.8

Amortization	(0.3)		(3.3)
Ending balance	$	3.2	$	4.5
Contract liabilities: Deferred revenue
Beginning balance	$	205.6	$	448.2

Revenue recognized from balances held at the beginning of the period	(15.6)		(188.8)

Ending balance	$	190.0	$	259.4

The aggregate amount of the transaction price allocated to performance obligations that were unsatisfied as of March 31, 2026 totaled $190.0 million, which is expected to be recognized in the following periods:


(dollars in millions)
Remainder of 2026	$	46.7
2027	20.3
2028	20.3
2029	102.7



Total	$	190.0

Summary of Accounting Pronouncements and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2026
Accounting Policies [Abstract]
Summary of Accounting Pronouncements and Significant Accounting Policies	Summary of Accounting Pronouncements and Significant Accounting Policies Accounting Pronouncements Recently Adopted Accounting Pronouncements There have been no recently adopted accounting pronouncements that have had a material impact on the Company's unaudited condensed consolidated financial statements. Recently Issued Accounting Pronouncements Not Yet Adopted Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40) - In November 2024, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2024-03, "Disaggregation of Income Statement Expenses," which requires disclosures of certain disaggregated income statement expense captions into specified categories within the footnotes to the financial statements. The requirements of the ASU are effective for annual periods beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027, with early adoption permitted. The requirements will be applied prospectively with the option for retrospective application. The Company is currently evaluating the impact ASU No. 2024-03 will have on its condensed consolidated financial statements. Significant Accounting Policies There were no changes to the Company’s significant accounting policies during the three months ended March 31, 2026.

Long-Term Debt - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended
	Sep. 30, 2018	Mar. 31, 2026
Debt Instrument [Line Items]
Debt instrument bearing interest rate		3.25%
2018 Assistance Agreement \| State of Connecticut
Debt Instrument [Line Items]
Debt instrument face amount	$ 2.0
Loan forgiveness	$ 1.0
Debt instrument bearing interest rate	3.25%
Debt instrument interest payments term (in months)	60 months
Percentage of liquidated damages	7.50%

- 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

Long-Term Debt

3 Months Ended

Mar. 31, 2026

Debt Disclosure [Abstract]

Long-Term Debt

Debt obligations consisted of the following:


(dollars in millions)	Maturity Date	Interest Rate	March 31, 2026		December 31, 2025
2018 Assistance Agreement Debt	09/28	3.25%	$	0.5	$	0.6
Less: current installments included within Accounts payable and accrued liabilities			(0.2)		(0.2)
Total long-term debt			$	0.3	$	0.4

In June 2018, the Company entered into an assistance agreement with the State of Connecticut (the "2018 Assistance Agreement") to provide funding for the expansion and renovation of laboratory and office space. The Company borrowed $2.0 million under the 2018 Assistance Agreement in September 2018, of which

$1.0 million was forgiven upon meeting certain employment conditions. Borrowings under the 2018 Assistance Agreement bear an interest rate of 3.25% per annum, with interest-only payments required for the first 60 months, and mature in September 2028. The 2018 Assistance Agreement requires that the Company be located in the State of Connecticut through September 2028, with a default penalty of repayment of the full original funding amount of $2.0 million plus liquidated damages of 7.5% of the total amount of funding received.

Minimum future principal payments on long-term debt as of March 31, 2026 are as follows:


(dollars in millions)
Remainder of 2026	$	0.1
2027	0.2
2028	0.2


Total	$	0.5

During the three months ended March 31, 2026 and 2025, interest expense was immaterial.

- 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

Research Collaboration and License Agreements (Tables)

3 Months Ended

Mar. 31, 2026

Research Collaboration And License Agreements [Abstract]

Summary of Sources of Revenue

During the three months ended March 31, 2026 and 2025, the Company's sources of revenue were as follows:


(dollars in millions)	March 31, 2026		March 31, 2025
Revenue
Vepdegestrant (ARV-471) Collaboration Agreement	$	14.4	$	189.9
Pfizer Research Collaboration Agreement	1.2		(1.1)
Total Revenue	$	15.6	$	188.8

Schedule of Contract Balances

Changes in the Company's contract balances for the three months ended March 31, 2026 and 2025 were as follows:


(dollars in millions)	March 31, 2026		March 31, 2025
Accounts receivable related to collaborations
Beginning balance	$	1.0	$	5.7
Additions	0.8		—
Payments received	—		(5.3)
Ending balance	$	1.8	$	0.4
Accounts payable related to collaborations
Beginning balance	$	16.8	$	5.4
Additions	9.1		19.4
Payments made	—		(5.4)
Ending balance	$	25.9	$	19.4
Contract assets: Collaboration contract asset
Beginning balance	$	3.5	$	7.8

Amortization	(0.3)		(3.3)
Ending balance	$	3.2	$	4.5
Contract liabilities: Deferred revenue
Beginning balance	$	205.6	$	448.2

Revenue recognized from balances held at the beginning of the period	(15.6)		(188.8)

Ending balance	$	190.0	$	259.4

Schedule of Transaction Price Allocated to Performance Obligations


(dollars in millions)
Remainder of 2026	$	46.7
2027	20.3
2028	20.3
2029	102.7



Total	$	190.0

Long-Term Debt (Tables)

3 Months Ended

Mar. 31, 2026

Debt Disclosure [Abstract]

Schedule of Long-Term Debt

Debt obligations consisted of the following:


(dollars in millions)	Maturity Date	Interest Rate	March 31, 2026		December 31, 2025
2018 Assistance Agreement Debt	09/28	3.25%	$	0.5	$	0.6
Less: current installments included within Accounts payable and accrued liabilities			(0.2)		(0.2)
Total long-term debt			$	0.3	$	0.4

Schedule of Minimum Future Payments on Long-Term Debt

Minimum future principal payments on long-term debt as of March 31, 2026 are as follows:


(dollars in millions)
Remainder of 2026	$	0.1
2027	0.2
2028	0.2


Total	$	0.5

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

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+ Details

Right-of-Use Assets and Liabilities - Components of Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Leases [Abstract]
Operating lease cost	$ 0.6	$ 0.7

Research Collaboration and License Agreements - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		4 Months Ended	12 Months Ended
	Nov. 30, 2017	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2015	Dec. 31, 2018	Dec. 31, 2025	Dec. 31, 2024	Jun. 18, 2024	May 31, 2024	Jul. 31, 2021	Dec. 31, 2017
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved		$ 3.2	$ 4.5			$ 3.5	$ 7.8
Collaboration contract asset and other assets		3.5				3.8
Contract with customer, liability		190.0	259.4			$ 205.6	$ 448.2
Revenue		15.6	188.8
Operating expenses		(79.4)	(117.4)
Net loss		$ (57.6)	$ 82.9
Basic (in dollars per share)		$ (0.90)	$ 1.14
Diluted (in dollars per share)		$ (0.90)	$ 1.14
Removal of Combination Trials
Research Collaboration And License Agreements [Line Items]
Revenue			$ 150.2
Operating expenses			(2.6)
Net loss			$ (147.6)
Basic (in dollars per share)			$ 2.04
Diluted (in dollars per share)			$ 2.03
Updated Research Timelines
Research Collaboration And License Agreements [Line Items]
Revenue			$ (2.5)
Net loss			$ (2.5)
Basic (in dollars per share)			$ 0.03
Diluted (in dollars per share)			$ 0.03
Pfizer, Inc.
Research Collaboration And License Agreements [Line Items]
Payments received					$ 28.0
Revenue		$ 1.2	$ (1.1)
Pfizer, Inc. \| Collaboration Agreement
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved										$ 650.0
Collaboration agreement direct and incremental costs incurred		12.9
Collaboration contract asset and other assets		12.9
Pfizer, Inc. \| Regulatory and Sales-Based Milestones \| Maximum
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved										1,400.0
Pfizer, Inc. \| Regulatory Milestone Related to Marketing Approvals
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved										400.0
Pfizer, Inc. \| Sales-Based Milestones
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved										$ 1,000.0
Pfizer, Inc. \| Option Payments To License Agreement \| Maximum
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved		3.8
Pfizer, Inc. \| Development Milestone Payments
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved								$ 50.0
Pfizer, Inc. \| Development Milestone Payments \| Maximum
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved											$ 225.0
Pfizer, Inc. \| Sales Based Milestone Payments \| Maximum
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved											$ 550.0
Novartis Pharma AG \| License
Research Collaboration And License Agreements [Line Items]
Contract with customer, liability									$ 150.0
Contingent payments									$ 1,010.0
Genentech
Research Collaboration And License Agreements [Line Items]
Payments received	$ 34.5			$ 11.0
Genentech \| Regulatory Milestone Related to Marketing Approvals
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved		52.5
Genentech \| Development Milestone Payments \| Maximum
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved		44.0
Genentech \| Commercial Milestones
Research Collaboration And License Agreements [Line Items]
Contract revenue receivable if milestones achieved		$ 60.0

Property, Equipment and Leasehold Improvements - Schedule of Property, Equipment and Leasehold Improvements (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Property Plant And Equipment [Line Items]
Total property, equipment and leasehold improvements	$ 34.0	$ 33.4
Less: accumulated depreciation and amortization	(28.5)	(28.2)
Property, equipment and leasehold improvements, net	5.5	5.2
Laboratory equipment
Property Plant And Equipment [Line Items]
Total property, equipment and leasehold improvements	21.7	21.3
Leasehold improvements
Property Plant And Equipment [Line Items]
Total property, equipment and leasehold improvements	9.1	9.1
Office equipment
Property Plant And Equipment [Line Items]
Total property, equipment and leasehold improvements	$ 3.2	$ 3.0

Research Collaboration and License Agreements - Schedule of Contract Balances (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Accounts receivable related to collaborations
Beginning balance	$ 1.0	$ 5.7
Additions	0.8	0.0
Payments received	0.0	(5.3)
Ending balance	1.8	0.4
Accounts payable related to collaborations
Beginning balance	16.8	5.4
Additions	9.1	19.4
Payments made	0.0	(5.4)
Ending balance	25.9	19.4
Contract assets: Collaboration contract asset
Beginning balance	3.5	7.8
Amortization	(0.3)	(3.3)
Ending balance	3.2	4.5
Contract liabilities: Deferred revenue
Beginning balance	205.6	448.2
Revenue recognized from balances held at the beginning of the period	(15.6)	(188.8)
Ending balance	$ 190.0	$ 259.4

Research Collaboration and License Agreements - Summary of Sources of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Research Collaboration And License Agreements [Line Items]
Revenue	$ 15.6	$ 188.8
Vepdegestrant
Research Collaboration And License Agreements [Line Items]
Revenue	14.4	189.9
Pfizer, Inc.
Research Collaboration And License Agreements [Line Items]
Revenue	$ 1.2	$ (1.1)

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Marketable Securities and Fair Value Measurements

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Marketable Securities and Fair Value Measurements

The following is a summary of the Company’s available-for-sale marketable securities measured at fair value on a recurring basis.


	March 31, 2026
(dollars in millions)	Valuation Hierarchy	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Corporate bonds	Level 2	$	503.6	$	0.3	$	(0.7)	$	503.2
Government securities	Level 2	24.4		—		—		24.4
Total		$	528.0	$	0.3	$	(0.7)	$	527.6


	December 31, 2025
(dollars in millions)	Valuation Hierarchy	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Corporate bonds	Level 2	$	528.0	$	1.1	$	—	$	529.1
Government securities	Level 2	13.3		0.1		—		13.4
Total		$	541.3	$	1.2	$	—	$	542.5

The Company generally does not intend to sell any investments prior to recovery of their amortized cost basis for any investment in an unrealized loss position. As such, the Company has classified these losses as temporary in nature.

The carrying value of cash and cash equivalents, accounts receivable and accounts payable and accrued liabilities approximate their fair values due to the short-term nature of these assets and liabilities.

- 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)
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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+ Details

Loss Per Common Share (Tables)

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Schedule of Basic and Diluted Loss per Common Share

Basic and diluted loss per common share was calculated as follows:


	For the Three Months Ended March 31,
(dollars and shares in millions, except per share amounts)	2026		2025
Net loss	$	(57.6)	$	82.9

Weighted average common shares outstanding - basic	64.0		72.5
Denominator adjustments for diluted EPS:
Number of stock options and RSUs	—		0.2
Denominator adjustments for diluted EPS:	—		0.2
Diluted weighted average common shares outstanding	64.0		72.7

Loss per common share
Basic	$	(0.90)	$	1.14
Diluted	$	(0.90)	$	1.14

Schedule of Securities Excluded From Computation of Diluted Net Loss Per Common Share

The Company reported net losses for the three months ended March 31, 2026 and therefore excluded all stock options and RSUs from the calculation of diluted net loss per common share as their inclusion would have had an anti-dilutive effect, as summarized below:


			For the Three Months Ended March 31,
			2026
Stock options			9.4

RSUs			4.4
			13.8

Property, Equipment and Leasehold Improvements - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 0.7	$ 0.7

Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Payables and Accruals [Abstract]
Accounts payable	$ 31.4	$ 24.4
Accrued liabilities
Research and development expenses	17.4	18.2
Employee expenses	4.5	17.5
Income taxes	5.0	4.8
General and administrative and commercial expenses	2.4	3.7
Professional fees	1.6	0.9
Total accounts payable and accrued liabilities	$ 62.3	$ 69.5

Accounts Payable and Accrued Liabilities (Tables)

3 Months Ended

Mar. 31, 2026

Payables and Accruals [Abstract]

Schedule of Components of Accounts Payable and Accrued Liabilities

Accounts payable and accrued liabilities consisted of the following:


(dollars in millions)	March 31, 2026		December 31, 2025
Accounts payable	$	31.4	$	24.4
Accrued liabilities
Research and development expenses	17.4		18.2
Employee expenses	4.5		17.5
Income taxes	5.0		4.8
General and administrative and commercial expenses	2.4		3.7
Professional fees	1.6		0.9
Total accounts payable and accrued liabilities	$	62.3	$	69.5

Summary of Accounting Pronouncements and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2026
Accounting Policies [Abstract]
Basis of Presentation	The accompanying unaudited condensed consolidated financial statements include the accounts of Arvinas, Inc. and its subsidiaries. The financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X under the Securities Exchange Act of 1934, as amended (“Exchange Act”). Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to U.S. Securities and Exchange Commission (“SEC”) rules. In the opinion of management, all adjustments (consisting of normal recurring adjustments) necessary for a fair presentation have been included. The condensed consolidated balance sheet as of December 31, 2025 has been derived from the Company's audited consolidated financial statements as of that date. The financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2025, forming part of Arvinas’ 2025 Annual Report on Form 10-K filed with the SEC on February 24, 2026.
Use of Estimates	The preparation of the Company’s unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amount of assets, liabilities, revenue and expenses. These estimates include assumptions and judgments based on historical experience, current conditions, future expectations and other factors the Company considers reasonable. These estimates are reviewed on an ongoing basis and revised as necessary. Actual results could differ from these estimates.
Risks and Uncertainties	Risks and Uncertainties The Company is subject to a number of risks similar to other biotechnology companies in a similar stage, including, but not limited to, the need to obtain adequate additional funding, possible failure of preclinical testing or clinical trials, the need to obtain marketing approval for its product candidates, competitors developing new technological innovations, and the need to successfully commercialize and gain market acceptance of the Company’s products and to protect its proprietary technology. If the Company does not successfully obtain regulatory approval of its product candidates, it will be unable to generate revenue from product sales or achieve profitability.
Accounting Pronouncements	Accounting Pronouncements Recently Adopted Accounting Pronouncements There have been no recently adopted accounting pronouncements that have had a material impact on the Company's unaudited condensed consolidated financial statements. Recently Issued Accounting Pronouncements Not Yet Adopted Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40) - In November 2024, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2024-03, "Disaggregation of Income Statement Expenses," which requires disclosures of certain disaggregated income statement expense captions into specified categories within the footnotes to the financial statements. The requirements of the ASU are effective for annual periods beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027, with early adoption permitted. The requirements will be applied prospectively with the option for retrospective application. The Company is currently evaluating the impact ASU No. 2024-03 will have on its condensed consolidated financial statements.

- 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

Marketable Securities and Fair Value Measurements (Details) - Level 2 - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	$ 528.0	$ 541.3
Gross Unrealized Gains	0.3	1.2
Gross Unrealized Losses	(0.7)	0.0
Fair Value	527.6	542.5
Corporate bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	503.6	528.0
Gross Unrealized Gains	0.3	1.1
Gross Unrealized Losses	(0.7)	0.0
Fair Value	503.2	529.1
Government securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	24.4	13.3
Gross Unrealized Gains	0.0	0.1
Gross Unrealized Losses	0.0	0.0
Fair Value	$ 24.4	$ 13.4

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Sep. 30, 2018	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2019	Nov. 30, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense		$ 12.1	$ 15.0
Compensation expense not yet recognized		$ 45.8
Inducement grants (in shares)		255,611
Weighted-average grant date fair value of options (in dollars per share)		$ 9.06	$ 11.50
Intrinsic value of options exercised		$ 0.0	$ 0.0
Weighted Average
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense not yet recognized, period of recognition (in years)		1 year 10 months 24 days
2018 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance (in shares)	4,067,007
Common stock, shares remained available for purchase (in shares)		2,981,638
Annual increase in reserved shares as percentage of outstanding common stock				4.00%
2018 Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance (in shares)	1,277,181
2018 Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual increase in reserved shares of common stock (in shares)				4,989,593
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance (in shares)	311,850
Common stock reserved for issuance represented as percentage on outstanding common stock	1.00%
Common stock, shares remained available for purchase (in shares)		4,212,347
Common stock, shares issued (in shares)		0	0
ESPP \| 2018 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense		$ 0.1	$ 0.2
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of inducement grants (in shares)		127,774
Granted (in dollars per share)		$ 13.38	$ 17.66
Total intrinsic value of RSUs released		$ 11.8	$ 14.1
Total fair value of RSUs vested		$ 31.1	$ 36.5
RSUs \| 2018 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted (in dollars per share)		$ 13.38
Piper Sandler and Cantor \| At-the-Market Offering \| Equity Distribution Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock aggregate offering price					$ 262.8
Common stock issued, net of issuance costs (in shares)		0

Loss Per Common Share

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Loss Per Common Share

Basic and diluted loss per common share was calculated as follows:


	For the Three Months Ended March 31,
(dollars and shares in millions, except per share amounts)	2026		2025
Net loss	$	(57.6)	$	82.9

Weighted average common shares outstanding - basic	64.0		72.5
Denominator adjustments for diluted EPS:
Number of stock options and RSUs	—		0.2
Denominator adjustments for diluted EPS:	—		0.2
Diluted weighted average common shares outstanding	64.0		72.7

Loss per common share
Basic	$	(0.90)	$	1.14
Diluted	$	(0.90)	$	1.14

Treasury shares are not considered outstanding and are excluded from the calculation of basic and diluted loss per common share.


			For the Three Months Ended March 31,
			2026
Stock options			9.4

RSUs			4.4
			13.8

Right of Use Assets and Liabilities - Schedule of Supplemental Cash Flow Information Related to Leases (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 0.4	$ 0.5
Supplemental non-cash information:
Right-of-use assets obtained in exchange for new lease obligations	$ 0.0	$ 1.5

Segment Information - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2026 USD ($) segment	Mar. 31, 2025 USD ($)
Segment Reporting [Abstract]
Number of operating segments	1
Number of reportable segments	1
Depreciation and amortization \| $	$ 0.7	$ 0.7

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
Income Tax Disclosure [Abstract]
Income tax expense	$ 0.1	$ 0.2
Effective tax rate, percentage	(0.20%)	0.20%
Federal statutory rate, percentage	21.00%	21.00%

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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+ Details

Related Party Transactions (Details)	1 Months Ended	3 Months Ended
Related Party Transactions (Details)	Mar. 31, 2026 USD ($) h	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)
Related Party Transaction [Line Items]
General and administrative		$ 19,100,000	$ 26,600,000
Director
Related Party Transaction [Line Items]
Hourly rate	$ 500
Hours worked in a month before hourly rate applies \| h	8
General and administrative		$ 500,000
Director \| Consulting Agreement, Lump Sum Payment
Related Party Transaction [Line Items]
Related party transaction	$ 457,000,000
Director \| Consulting Agreement, COBRA Reimbursement
Related Party Transaction [Line Items]
Related party transaction	$ 27,914,000

- 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

Equity - Summary of Stock Option Activity (Details) - 2018 Plan - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Options
Beginning balance (in shares)	8,631,075
Granted (in shares)	905,449
Cancelled/ Forfeited (in shares)	(144,146)
Ending balance (in shares)	9,392,378	8,631,075
Vested and exercisable, ending balance (in shares)	6,202,436
Vested and expected to vest (in shares)	9,000,947
Weighted Average Exercise Price
Beginning balance (in dollars per share)	$ 35.89
Granted (in dollars per share)	13.38
Cancelled/ Forfeited (in dollars per share)	45.57
Ending balance (in dollars per share)	33.57	$ 35.89
Vested and exercisable (in dollars per share)	43.09
Vested and expected to vest (in dollars per share)	$ 34.35
Weighted Average Remaining Contractual Term (Years)
Outstanding (in years)	6 years 7 months 6 days	6 years 6 months
Vested and exercisable (in years)	5 years 3 months 18 days
Vested and expected to vest (in Years)	6 years 6 months
Aggregate Intrinsic Value
Outstanding	$ 3.9	$ 5.3
Vested and exercisable	0.0
Vested and expected to vest	$ 3.7

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2026
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For the three months ended March 31, 2026, the Company recognized income tax expense of $0.1 million, resulting in an effective tax rate of (0.2)%, as compared to income tax expense of $0.2 million, resulting in an effective tax rate of 0.2%, in the same period for 2025. The primary reconciling items between the federal statutory rate of 21.0% for the three months ended March 31, 2026 and the Company’s overall effective tax rate of (0.2)% was the effect of equity compensation and the valuation allowance recorded against the full amount of its net deferred tax assets. The primary reconciling items between the federal statutory rate of 21.0% for the three months ended March 31, 2025 and the Company’s overall effective tax rate of 0.2% was the effect of equity compensation and the valuation allowance recorded against the full amount of its net deferred tax assets. A valuation allowance is established when it is more likely than not that some portion or all of a deferred tax asset will not be realized. The realization of deferred tax assets depends on the generation of future taxable income during the period in which related temporary differences become deductible. The Company continues to establish a valuation allowance against the full amount of its net deferred tax assets since it is more likely than not that benefits will not be realized, including those benefits created in the current year. This assessment is based on the Company's historical cumulative losses, which provide strong objective evidence that cannot be overcome with projections of income, as well as the fact the Company expects continuing losses in the future.

- Definition

The entire disclosure for income tax.

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+ Details

Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2026	May 07, 2026
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Transition Report	false
Entity File Number	001-38672
Entity Registrant Name	ARVINAS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-2566120
Entity Address, Address Line One	5 Science Park
Entity Address, Address Line Two	395 Winchester Ave
Entity Address, City or Town	New Haven
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06511
City Area Code	203
Local Phone Number	535-1456
Title of 12(b) Security	Common stock, par value $0.001 per share
Trading Symbol	ARVN
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		64,521,198
Amendment Flag	false
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001655759
Current Fiscal Year End Date	--12-31

Long-Term Debt - Schedule of Minimum Future Payments on Long-Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Debt Disclosure [Abstract]
Remainder of 2026	$ 0.1
2027	0.2
2028	0.2
Total	$ 0.5	$ 0.6

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

+ Details

Related Party Transactions	3 Months Ended
Related Party Transactions	Mar. 31, 2026
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Consulting Agreement On February 12, 2026, the Company entered into a consulting agreement with John Houston, Ph.D., the Company’s former President and Chief Executive Officer and a current member of its Board of Directors. Under the terms of the agreement, Dr. Houston will provide consulting and advisory services to the Company until March 1, 2027. Pursuant to the agreement, the Company agreed to (i) pay Dr. Houston a lump sum of $457,000 in March 2026, which amount was equivalent to the amount that Dr. Houston would have received as an employee for a 2025 bonus based on achievement of our 2025 corporate goals as approved by the Company's board of directors, had he continued to be employed by the Company as President and Chief Executive Officer on the date of payment, (ii) reimburse Dr. Houston for up to $27,914 in COBRA health continuation coverage, subject to his election of such coverage, (iii) pay an hourly rate of $500 for services provided in excess of eight hours per month. The vesting of Dr. Houston's previously-granted equity continued pursuant to terms of the relevant grant agreements. During the three months ended March 31, 2026, the Company recognized expenses totaling $0.5 million related to this agreement, which are reflected in general and administrative expenses in the accompanying unaudited condensed consolidated financial statements.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

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+ Details

Equity - Schedule of Assumptions Used to Determine Fair Value of and Stock Options Granted (Details) - Stock options - $ / shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility, minimum (percentage)	77.50%	72.10%
Expected volatility, maximum (percentage)	77.50%	72.20%
Risk free interest rate, minimum (percentage)	3.60%	4.00%
Risk free interest rate, maximum (percentage)	3.60%	4.40%
Expected dividend yield (percentage)	0.00%	0.00%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)	5 years 7 months 6 days	5 years 6 months
Exercise price (in dollars per share)	$ 13.38	$ 16.23
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)	5 years 7 months 6 days	5 years 7 months 6 days
Exercise price (in dollars per share)	$ 13.38	$ 17.70

Insider Trading Arrangements

3 Months Ended

Mar. 31, 2026

Trading Arrangements, by Individual

Material Terms of Trading Arrangement

The following table describes, for the first quarter of 2026, each trading arrangement for the sale or purchase of Company securities adopted or terminated by our directors and officers that is either (1) a contract, instruction or written plan intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) (a “Rule 10b5-1 trading arrangement”) or (2) a “non-Rule 10b5-1 trading arrangement” (as defined in Item 408(c) of Regulation S-K):

Name (Title)

Action Taken (Date of Action)

Type of Trading Arrangement

Nature of Trading Arrangement

Duration of Trading Arrangement

Aggregate Number of Securities (1)

Randy Teel, Ph.D. (President, Chief Executive Officer, and Director)

2/27/2026

Durable Rule 10b5-1 trading arrangement for sell-to-cover transactions relating to all equity awards that were granted on or after February 26, 2026; and all equity awards granted prior to February 26, 2026 that vest after the relevant cooling off period

Sale

Until final settlement of any restricted stock units, or RSUs

Indeterminable

Andrew Saik (Chief Financial Officer and Treasurer)

2/27/2026

Sale

Until final settlement of any RSUs

Indeterminable

Noah Berkowitz, M.D., Ph.D. (Chief Medical Officer)

2/27/2026

Sale

Until final settlement of any RSUs

Indeterminable

Angela Cacace, Ph.D. (Chief Scientific Officer)

2/27/2026

Sale

Until final settlement of any RSUs

Indeterminable

David Loomis (VP, Chief Accounting Officer)

2/27/2026

Sale

Until final settlement of any RSUs

Indeterminable

(1) The number of shares subject to RSUs that will be sold to satisfy applicable tax withholding obligations upon vesting is unknown as the number will vary based on the extent to which vesting conditions are satisfied, the market price of the Company’s common stock at the time of settlement and the potential future grant of additional RSUs subject to this arrangement. This trading arrangement, which applies to RSUs whether vesting is based on the passage of time and/or the achievement of performance goals, provides for the automatic sale of shares that would otherwise be issuable on each settlement date of a RSU in an amount sufficient to satisfy the applicable tax withholding obligation, with the proceeds of the sale delivered to the Company in satisfaction of the applicable tax withholding obligation.

Non-Rule 10b5-1 Arrangement Adopted

false

Rule 10b5-1 Arrangement Terminated

false

Non-Rule 10b5-1 Arrangement Terminated

false

Randy Teel [Member]

Trading Arrangements, by Individual

Name

Randy Teel

Title

President, Chief Executive Officer, and Director

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/27/2026

Andrew Saik [Member]

Trading Arrangements, by Individual

Name

Andrew Saik

Title

Chief Financial Officer and Treasurer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/27/2026

Noah Berkowitz [Member]

Trading Arrangements, by Individual

Name

Noah Berkowitz

Title

Chief Medical Officer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/27/2026

Angela Cacace [Member]

Trading Arrangements, by Individual

Name

Angela Cacace

Title

Chief Scientific Officer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/27/2026

David Loomis [Member]

Trading Arrangements, by Individual

Name

David Loomis

Title

VP, Chief Accounting Officer

Rule 10b5-1 Arrangement Adopted

true

Adoption Date

2/27/2026

Right-of-Use Assets and Liabilities - Additional Information (Details)	Mar. 31, 2026
Lessee Lease Description [Line Items]
Operating lease, weighted average remaining lease term (in years)	3 years 9 months 18 days
Minimum
Lessee Lease Description [Line Items]
Percentage of incremental borrowing for lease payments	7.00%

Right-of-Use Assets and Liabilities - Schedule of Maturities of Operating Lease Liabilities (Details) $ in Millions	Mar. 31, 2026 USD ($)
Leases [Abstract]
Remainder of 2026	$ 1.7
2027	2.4
2028	2.5
2029	2.6
2030	0.0
Total lease payments	9.2
Less: imputed interest	(1.1)
Total	$ 8.1

Restructuring Activity	3 Months Ended
Restructuring Activity	Mar. 31, 2026
Restructuring and Related Activities [Abstract]
Restructuring Activity	Restructuring Activity In September 2025, the Company announced an update on its collaboration with Pfizer and further actions to support value creation by optimizing organizational and cost structures and streamlining operations in advance of multiple anticipated upcoming value inflection points, including: further limiting additional expenditures on the vepdegestrant program to support activities required for commercialization readiness and identification, with Pfizer, of a third party for the commercialization and potential further development of vepdegestrant; reducing the Company's workforce by 15% to streamline operations, with the most significant reductions being roles related to vepdegestrant commercialization; and proactively managing pipeline cost by seeking strategic business development opportunities and by identifying further efficiencies across the business. The September 2025 workforce reduction is expected to be completed by the second quarter of 2026. Components of Restructuring Charges During the three months ended March 31, 2026, the Company recognized net restructuring related charges of $1.1 million, comprised primarily of non-cash stock compensation, of which $0.3 million of charges are reflected in research and development expenses and $0.8 million are reflected in general and administrative expenses in the accompanying unaudited condensed consolidated financial statements. The Company's restructuring accrual totaled $1.6 million and $4.4 million as of March 31, 2026 and December 31, 2025, respectively.

Equity (Tables)

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

Schedule of Assumptions Used to Determine Fair Value of Stock Options Granted

The fair value of the stock options granted during the three months ended March 31, 2026 and 2025 was determined using the Black-Scholes option pricing model with the following assumptions:


	March 31, 2026		March 31, 2025
Expected volatility (1)	77.5% - 77.5%		72.1% - 72.2%
Expected term (years) (2)	5.6 - 5.6		5.5 - 5.6
Risk free interest rate (3)	3.6% - 3.6%		4.0% - 4.4%
Expected dividend yield	0	%	0	%
Exercise price	$13.38 - $13.38		$16.23 - $17.70

(1) Expected volatility is calculated by utilizing the Company's historical volatility of its stock price over a period equal to the expected term.

(2) Expected term is calculated based on the Company's historical experience.

(3) Risk free interest rate is based on an interpolation of U.S. Treasury rates to reflect the expected term at the date of grant.

Schedule of Stock Option Activity

A summary of the stock option activity under the 2018 Plan during the three months ended March 31, 2026 is presented below. Included in the table are stock options granted to employees, directors and consultants under the 2018 Plan, as well as options to purchase 255,611 shares of common stock granted to certain employees pursuant to the Nasdaq inducement grant exception in accordance with Nasdaq Listing Rule 5635(c)(4).


(dollars in millions, except weighted average exercise price)	Options	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding as of December 31, 2025	8,631,075	$	35.89	6.5	$	5.3
Granted	905,449	$	13.38

Cancelled / Forfeited	(144,146)	$	45.57

Outstanding as of March 31, 2026	9,392,378	$	33.57	6.6	$	3.9
Vested and exercisable as of March 31, 2026	6,202,436	$	43.09	5.3	$	—
Vested and expected to vest as of March 31, 2026	9,000,947	$	34.35	6.5	$	3.7

Schedule of Restricted Stock Grant Activity

A summary of RSU activity under the 2018 Plan during the three months ended March 31, 2026 is presented below. Included in the table are RSUs granted to employees, directors and consultants under the

2018 Plan, as well as RSUs representing 127,774 shares of common stock granted to certain employees pursuant to the Nasdaq inducement grant exception in accordance with Nasdaq Listing Rule 5635(c)(4).


	Shares	Weighted Average Grant Date Fair Value Per Share
Unvested RSUs as of December 31, 2025	3,624,051	$	18.59
Granted	1,853,715	$	13.38
Vested	(979,308)	$	31.80
Cancelled / Forfeited	(88,961)	$	7.71
Unvested RSUs as of March 31, 2026	4,409,497	$	13.68

Right-of-Use Assets and Liabilities

3 Months Ended

Mar. 31, 2026

Leases [Abstract]

Right-of-Use Assets and Liabilities

Operating lease liabilities and their corresponding right-of-use ("ROU") assets are recorded based on the present value of lease payments over the expected remaining lease term. The interest rate implicit in lease contracts is typically not readily determinable. As a result, the Company utilizes its incremental borrowing rate, which reflects the fixed rate at which it could borrow on a collateralized basis the amount of the lease payments in the same currency, for a similar term, in a similar economic environment. The Company's weighted average incremental borrowing rate at March 31, 2026 totaled 7.0%. Lease expense is recognized on a straight-line basis over the lease term.

The Company has an operating lease, as amended, for its corporate office and laboratories, which expires no later than December 2029. The lease has a weighted average remaining term of approximately 3.8 years.

The components of lease expense were as follows:


	Three Months Ended March 31,
(dollars in millions)	2026		2025
Operating lease cost	$	0.6	$	0.7

Supplemental cash flow information related to leases was as follows:


	Three Months Ended March 31,
(dollars in millions)	2026		2025
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	0.4	$	0.5
Supplemental non-cash information:
Right-of-use assets obtained in exchange for new lease obligations	$	—	$	1.5

Maturities of operating lease liabilities as of March 31, 2026, were as follows:


(dollars in millions)
Remainder of 2026	$	1.7
2027	2.4
2028	2.5
2029	2.6
2030	—


Total lease payments	9.2
Less: imputed interest	(1.1)
Total	$	8.1

Equity - Summary of Restricted Stock (Details) - RSUs - $ / shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Weighted Average Grant Date Fair Value Per Share
Granted (in dollars per share)	$ 13.38	$ 17.66
2018 Plan
Shares
Beginning balance (in shares)	3,624,051
Granted (in shares)	1,853,715
Vested (in shares)	(979,308)
Cancelled/ Forfeited (in shares)	(88,961)
Ending balance (in shares)	4,409,497
Weighted Average Grant Date Fair Value Per Share
Beginning balance (in dollars per share)	$ 18.59
Granted (in dollars per share)	13.38
Vested (in dollars per share)	31.80
Cancelled/ Forfeited (in dollars per share)	7.71
Ending balance (in dollars per share)	$ 13.68

Loss Per Common Share - Schedule of Basic and Diluted Loss per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Earnings Per Share [Abstract]
Net (loss) income	$ (57.6)	$ 82.9
Weighted average common shares outstanding - basic (in shares)	64.0	72.5
Number of stock options and RSUs (in shares)	0.0	0.2
Denominator adjustments for diluted EPS (in shares)	0.0	0.2
Weighted average common shares outstanding - diluted (in shares)	64.0	72.7
Loss per common share
Basic (in dollars per share)	$ (0.90)	$ 1.14
Diluted (in dollars per share)	$ (0.90)	$ 1.14

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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Reference 28: http://www.xbrl.org/2003/role/disclosureRef
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Reference 32: http://www.xbrl.org/2003/role/disclosureRef
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Reference 38: http://www.xbrl.org/2003/role/disclosureRef
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Reference 43: http://www.xbrl.org/2003/role/disclosureRef
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Reference 46: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Loss Per Common Share - Securities Excluded From Computation of Diluted Net Loss Per Common Share (Details) shares in Millions	3 Months Ended
	Mar. 31, 2026 shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per common share (in shares)	13.8
Stock options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per common share (in shares)	9.4
RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per common share (in shares)	4.4

Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 87.3	$ 142.9
Marketable securities	527.6	542.5
Accounts receivable	1.8	1.0
Other receivables	4.6	5.4
Prepaid expenses and other current assets	9.4	8.9
Total current assets	630.7	700.7
Property, equipment and leasehold improvements, net	5.5	5.2
Operating lease right-of-use assets	7.8	8.2
Collaboration contract asset and other assets	3.5	3.8
Total assets	647.5	717.9
Current liabilities:
Accounts payable and accrued liabilities	62.3	69.5
Deferred revenue	51.8	71.3
Current portion of operating lease liabilities	1.8	1.7
Total current liabilities	115.9	142.5
Deferred revenue	138.2	134.3
Long-term debt	0.3	0.4
Operating lease liabilities	6.3	6.8
Total liabilities	260.7	284.0
Commitments and Contingencies (Note 12)
Stockholders’ equity:
Preferred stock, $0.001 par value, zero shares issued and outstanding as of March 31, 2026 and December 31, 2025, respectively	0.0	0.0
Common stock, $0.001 par value; 74.5 shares issued and 64.5 shares outstanding as of March 31, 2026, and 73.5 shares issued and 63.5 outstanding as of December 31, 2025	$ 0.1	$ 0.1
Number Of Authorized Shares Not Disclosed	true	true
Accumulated deficit	$ (1,670.0)	$ (1,612.4)
Additional paid-in capital	2,149.0	2,136.9
Accumulated other comprehensive (loss) income	(0.4)	1.2
Treasury Stock, at cost (10.0 shares as of March 31, 2026 and December 31, 2025)	(91.9)	(91.9)
Total stockholders’ equity	386.8	433.9
Total liabilities and stockholders’ equity	$ 647.5	$ 717.9

Restructuring Activity (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Restructuring Activity (Details) - USD ($) $ in Millions	Sep. 30, 2025	Mar. 31, 2026	Dec. 31, 2025
Restructuring Cost and Reserve [Line Items]
Reduction in workforce (as a percent)	15.00%
Restructuring charges (income)		$ 1.1
Restructuring accrual		1.6	$ 4.4
Research and Development Expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges (income)		0.3
General and Administrative Expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges (income)		$ 0.8

- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References + Details

- 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

Condensed Consolidated Statements of Operations and Comprehensive (Loss) Income (unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Income Statement [Abstract]
Revenue	$ 15.6	$ 188.8
Operating expenses:
Research and development	60.3	90.8
General and administrative	19.1	26.6
Total operating expenses	79.4	117.4
(Loss) income from operations	(63.8)	71.4
Other income
Other expense, net	(0.1)	0.0
Interest income, net	6.4	11.7
Total other income	6.3	11.7
Net (loss) income before income taxes	(57.5)	83.1
Income tax expense	(0.1)	(0.2)
Net (loss) income	$ (57.6)	$ 82.9
(Loss) earnings per common share
Basic (in dollars per share)	$ (0.90)	$ 1.14
Diluted (in dollars per share)	$ (0.90)	$ 1.14
Weighted average common shares outstanding
Basic (in shares)	64.0	72.5
Diluted (in shares)	64.0	72.7
Condensed Consolidated Statements of Comprehensive Income (Loss)
Net (loss) income	$ (57.6)	$ 82.9
Other comprehensive loss:
Unrealized (loss) gain on available-for-sale securities	(1.6)	0.5
Comprehensive (loss) income	$ (59.2)	$ 83.4

Equity

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

Equity

Equity Distribution Agreements

In November 2023, the Company amended and restated the Equity Distribution Agreement with Piper Sandler & Company (“Piper Sandler”) and Cantor Fitzgerald & Co. (“Cantor”), as agents, pursuant to which the Company may offer and sell from time to time, through the agents, up to approximately $262.8 million of the common stock registered under a universal shelf registration statement pursuant to one or more “at-the-market” offerings. During the three months ended March 31, 2026, no shares were issued under this agreement.

Stock-based Compensation

2018 Employee Stock Purchase Plan

In September 2018, the Company adopted the 2018 Employee Stock Purchase Plan (the “2018 ESPP”), with the first offering period under the 2018 ESPP commencing on January 1, 2020, by initially providing participating employees with the opportunity to purchase an aggregate of 311,850 shares of the Company’s common stock. The number of shares of the Company’s common stock reserved for issuance under the 2018 ESPP increased, pursuant to the terms of the 2018 ESPP, by additional shares equal to 1% of the Company’s then-outstanding common stock, effective as of January 1 of each year. As of March 31, 2026, 4,212,347 shares remained available for purchase. During the three months ended March 31, 2026 and 2025, no shares of common stock were issued under the 2018 ESPP.

2018 Stock Incentive Plan

In September 2018, the Company’s board of directors adopted, and the Company’s stockholders approved, the 2018 Stock Incentive Plan (the “2018 Plan”), which became effective upon the effectiveness of the registration statement on Form S-1 for the Company’s initial public offering. The number of shares of common stock initially available for issuance under the 2018 Plan equaled the sum of (1) 4,067,007 shares of common stock; plus (2) the number of shares of common stock (up to 1,277,181 shares) issued in respect of incentive units granted under the Fourth Amendment to the Company’s Incentive Share Plan, which was terminated in September 2018, that were subject to vesting immediately prior to the effectiveness of the registration statement that expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right; plus (3) an annual increase on the first day of each fiscal year beginning with the fiscal year ended December 31, 2019 and continuing to, and including, the fiscal year ending December 31, 2028, equal to the lesser of 4,989,593 shares of the Company’s common stock, 4% of the number of shares of the Company’s common stock outstanding on the first day of the year or an amount determined by the Company’s board of directors. As of March 31, 2026, 2,981,638 shares remained available for issuance under the 2018 Plan. Shares of common stock subject to outstanding equity awards that expire or are terminated, surrendered or canceled without having been fully exercised or are forfeited in whole or in part are available for future grants of awards.

Compensation Expense

During the three months ended March 31, 2026 and 2025, the Company recognized compensation expense of $12.1 million and $15.0 million, respectively, related to the issuance of incentive awards, including $0.1 million and $0.2 million, respectively, related to the 2018 ESPP.

As of March 31, 2026, there was $45.8 million of total unrecognized compensation expense that is expected to be amortized over a weighted average period of approximately 1.9 years.

Stock Options

The fair value of the stock options granted during the three months ended March 31, 2026 and 2025 was determined using the Black-Scholes option pricing model with the following assumptions:


	March 31, 2026		March 31, 2025
Expected volatility (1)	77.5% - 77.5%		72.1% - 72.2%
Expected term (years) (2)	5.6 - 5.6		5.5 - 5.6
Risk free interest rate (3)	3.6% - 3.6%		4.0% - 4.4%
Expected dividend yield	0	%	0	%
Exercise price	$13.38 - $13.38		$16.23 - $17.70

(1) Expected volatility is calculated by utilizing the Company's historical volatility of its stock price over a period equal to the expected term.

(2) Expected term is calculated based on the Company's historical experience.

(3) Risk free interest rate is based on an interpolation of U.S. Treasury rates to reflect the expected term at the date of grant.


(dollars in millions, except weighted average exercise price)	Options	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding as of December 31, 2025	8,631,075	$	35.89	6.5	$	5.3
Granted	905,449	$	13.38

Cancelled / Forfeited	(144,146)	$	45.57

Outstanding as of March 31, 2026	9,392,378	$	33.57	6.6	$	3.9
Vested and exercisable as of March 31, 2026	6,202,436	$	43.09	5.3	$	—
Vested and expected to vest as of March 31, 2026	9,000,947	$	34.35	6.5	$	3.7

The weighted-average grant date fair value per share of options granted during the three months ended March 31, 2026 and 2025 was $9.06 and $11.50, respectively. There were no options exercised during the three months ended March 31, 2026 and 2025.

Restricted Stock Units ("RSUs")

A summary of RSU activity under the 2018 Plan during the three months ended March 31, 2026 is presented below. Included in the table are RSUs granted to employees, directors and consultants under the


	Shares	Weighted Average Grant Date Fair Value Per Share
Unvested RSUs as of December 31, 2025	3,624,051	$	18.59
Granted	1,853,715	$	13.38
Vested	(979,308)	$	31.80
Cancelled / Forfeited	(88,961)	$	7.71
Unvested RSUs as of March 31, 2026	4,409,497	$	13.68

The weighted-average grant date fair value per share of RSUs granted during the three months ended March 31, 2026 and 2025 was $13.38 and $17.66, respectively. The total intrinsic value of RSUs released during the three months ended March 31, 2026 and 2025 was $11.8 million and $14.1 million, respectively. The total fair value of RSUs vested during the three months ended March 31, 2026 and 2025 was $31.1 million and $36.5 million, respectively.

Accounts Payable and Accrued Liabilities

3 Months Ended

Mar. 31, 2026

Payables and Accruals [Abstract]

Accounts Payable and Accrued Liabilities

Accounts payable and accrued liabilities consisted of the following:


(dollars in millions)	March 31, 2026		December 31, 2025
Accounts payable	$	31.4	$	24.4
Accrued liabilities
Research and development expenses	17.4		18.2
Employee expenses	4.5		17.5
Income taxes	5.0		4.8
General and administrative and commercial expenses	2.4		3.7
Professional fees	1.6		0.9
Total accounts payable and accrued liabilities	$	62.3	$	69.5

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2026
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On May 1, 2026, the Company issued a press release announcing that the FDA has granted approval for VEPPANU™ (vepdegestrant) for the treatment of adults with ER+/ HER2-, ESR1-mutated advanced or metastatic breast cancer, as detected by an FDA-authorized test, with disease progression following at least one line of endocrine-based therapy. VEPPANU is the first-and-only FDA-approved PROteolysis TArgeting Chimera (PROTAC) protein degrader, a type of heterobifunctional protein degrader therapy. FDA approval was received in advance of FDA-assigned PDUFA date of June 5, 2026. The Company and its collaborator, Pfizer, remain on track to announce selection of a third party to commercialize VEPPANU. Pursuant to the Vepdegestrant (ARV-471) Collaboration Agreement, the Company will receive $50.0 million as the Milestone Payment. The Milestone Payment will be offset by certain amounts that the Company will owe to Yale pursuant to the

Subsequent Events (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 18, 2024
Subsequent Event [Line Items]
Contract revenue receivable if milestones achieved	$ 3.2	$ 3.5	$ 4.5	$ 7.8
Pfizer, Inc. \| Development Milestone Payments
Subsequent Event [Line Items]
Contract revenue receivable if milestones achieved					$ 50.0

Research Collaboration and License Agreements - Transaction Price Allocated to Performance Obligations (Details) $ in Millions	Mar. 31, 2026 USD ($)
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 190.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2026-04-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 46.7
Revenue, remaining performance obligation, expected timing of satisfaction, period	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2027-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 20.3
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2028-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 20.3
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2029-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 102.7
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year

Nature of Business and Basis of Presentation (Details) $ in Millions	Mar. 31, 2026 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash, cash equivalents, restricted cash and marketable securities	$ 614.9

Segment Information - Financial Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Revenue	$ 15.6	$ 188.8
Less:
Total research and development expense	60.3	90.8
General and administrative expense	19.1	26.6
Income tax expense	0.1	0.2
Interest income, net	6.4	11.7
Segment net (loss) income	(57.6)	82.9
Reportable Segment
Segment Reporting Information [Line Items]
Revenue	15.6	188.8
Less:
Non program-specific external expense	9.2	13.9
Compensation and related personnel expense (including stock-based compensation)	21.3	36.9
Other research and development expense	2.4	3.1
Total research and development expense	60.3	90.8
General and administrative expense	19.1	26.6
Other segment expense, net (**)	0.1	0.0
Income tax expense	0.1	0.2
Interest income, net	6.4	11.7
Segment net (loss) income	(57.6)	82.9
Reportable Segment \| Vepdegestrant ARV-471
Less:
Program-specific external expense	8.9	24.1
Reportable Segment \| ARV-806
Less:
Program-specific external expense	6.5	0.9
Reportable Segment \| ARV-102
Less:
Program-specific external expense	5.5	6.5
Reportable Segment \| ARV-393
Less:
Program-specific external expense	3.7	2.6
Reportable Segment \| Bavdegalutamide (ARV-110)
Less:
Program-specific external expense	0.2	1.1
Reportable Segment \| Other programs
Less:
Program-specific external expense	$ 2.6	$ 1.7

Property, Equipment and Leasehold Improvements

3 Months Ended

Mar. 31, 2026

Property, Plant and Equipment [Abstract]

Property, Equipment and Leasehold Improvements

Property, equipment and leasehold improvements consist of the following:


(dollars in millions)	March 31, 2026		December 31, 2025
Laboratory equipment	$	21.7	$	21.3
Leasehold improvements	9.1		9.1
Office equipment	3.2		3.0
Total property, equipment and leasehold improvements	34.0		33.4
Less: accumulated depreciation and amortization	(28.5)		(28.2)
Property, equipment and leasehold improvements, net	$	5.5	$	5.2

During each of the three months ended March 31, 2026 and 2025, the Company recognized depreciation and amortization expense of $0.7 million.

Nature of Business and Basis of Presentation	3 Months Ended
Nature of Business and Basis of Presentation	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business and Basis of Presentation	Nature of Business and Basis of Presentation Arvinas, Inc. and its subsidiaries (“Arvinas” or the "Company”) is a biotechnology company dedicated to improving the lives of patients suffering from debilitating and life-threatening diseases. The accompanying unaudited condensed consolidated financial statements include the accounts of Arvinas, Inc. and its subsidiaries. The financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X under the Securities Exchange Act of 1934, as amended (“Exchange Act”). Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to U.S. Securities and Exchange Commission (“SEC”) rules. In the opinion of management, all adjustments (consisting of normal recurring adjustments) necessary for a fair presentation have been included. The condensed consolidated balance sheet as of December 31, 2025 has been derived from the Company's audited consolidated financial statements as of that date. The financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2025, forming part of Arvinas’ 2025 Annual Report on Form 10-K filed with the SEC on February 24, 2026. The preparation of the Company’s unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amount of assets, liabilities, revenue and expenses. These estimates include assumptions and judgments based on historical experience, current conditions, future expectations and other factors the Company considers reasonable. These estimates are reviewed on an ongoing basis and revised as necessary. Actual results could differ from these estimates. Risks and Uncertainties The Company is subject to a number of risks similar to other biotechnology companies in a similar stage, including, but not limited to, the need to obtain adequate additional funding, possible failure of preclinical testing or clinical trials, the need to obtain marketing approval for its product candidates, competitors developing new technological innovations, and the need to successfully commercialize and gain market acceptance of the Company’s products and to protect its proprietary technology. If the Company does not successfully obtain regulatory approval of its product candidates, it will be unable to generate revenue from product sales or achieve profitability. To date, the Company has not generated any revenue from product sales and expects to incur additional operating losses and negative operating cash flows for the foreseeable future. The Company has financed its operations primarily through sales of assets and equity interests, proceeds from collaborations and a licensing arrangement, grant funding and debt financing. The Company had cash, cash equivalents and marketable securities of approximately $614.9 million as of March 31, 2026.

Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Cash flows from operating activities:
Net (loss) income	$ (57.6)	$ 82.9
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Depreciation and amortization	0.7	0.7
Net accretion of bond discounts/premiums	(1.7)	(3.8)
Amortization of right-of-use assets	0.4	0.6
Amortization of collaboration contract asset	0.3	3.3
Stock-based compensation	12.1	15.0
Changes in operating assets and liabilities:
Accounts receivable	(0.8)	5.3
Other receivables	0.8	0.0
Prepaid expenses and other assets	(0.6)	(2.7)
Accounts payable and accrued liabilities	(6.8)	(0.8)
Operating lease liability	(0.4)	(0.5)
Deferred revenue	(15.6)	(188.9)
Net cash used in operating activities	(69.2)	(88.9)
Cash flows from investing activities:
Purchases of marketable securities	(178.9)	(119.6)
Maturities of marketable securities	165.0	189.5
Sales of marketable securities	28.9	0.0
Purchases of property, equipment and leasehold improvements	(1.3)	(0.4)
Net cash provided by investing activities	13.7	69.5
Cash flows from financing activities:
Repayments of long-term debt	(0.1)	(0.1)
Net cash used in financing activities	(0.1)	(0.1)
Net decrease in cash and cash equivalents	(55.6)	(19.5)
Cash and cash equivalents, beginning of the period	142.9	100.5
Cash and cash equivalents, end of the period	87.3	81.0
Supplemental disclosure of cash flow information:
Purchases of property, equipment and leasehold improvements unpaid at period end	$ 0.0	$ 0.1

Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - $ / shares shares in Millions	Mar. 31, 2026	Dec. 31, 2025
Statement of Financial Position [Abstract]
Preferred stock par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares issued (in shares)	0.0	0.0
Preferred stock, shares outstanding (in shares)	0.0	0.0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares issued (in shares)	74.5	73.5
Common stock, shares outstanding (in shares)	64.5	63.5
Treasury stock (in shares)	10.0	10.0

Right-of-Use Assets and Liabilities (Tables)

3 Months Ended

Mar. 31, 2026

Leases [Abstract]

Schedule of Components of Lease Expense

The components of lease expense were as follows:


	Three Months Ended March 31,
(dollars in millions)	2026		2025
Operating lease cost	$	0.6	$	0.7

Schedule of Supplemental Cash Flow Information Related to Leases

Supplemental cash flow information related to leases was as follows:


	Three Months Ended March 31,
(dollars in millions)	2026		2025
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	0.4	$	0.5
Supplemental non-cash information:
Right-of-use assets obtained in exchange for new lease obligations	$	—	$	1.5

Schedule of Maturities of Operating Lease Liabilities

Maturities of operating lease liabilities as of March 31, 2026, were as follows:


(dollars in millions)
Remainder of 2026	$	1.7
2027	2.4
2028	2.5
2029	2.6
2030	—


Total lease payments	9.2
Less: imputed interest	(1.1)
Total	$	8.1

Marketable Securities and Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Schedule of Available-for-Sale Marketable Securities

The following is a summary of the Company’s available-for-sale marketable securities measured at fair value on a recurring basis.


	March 31, 2026
(dollars in millions)	Valuation Hierarchy	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Corporate bonds	Level 2	$	503.6	$	0.3	$	(0.7)	$	503.2
Government securities	Level 2	24.4		—		—		24.4
Total		$	528.0	$	0.3	$	(0.7)	$	527.6


	December 31, 2025
(dollars in millions)	Valuation Hierarchy	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Corporate bonds	Level 2	$	528.0	$	1.1	$	—	$	529.1
Government securities	Level 2	13.3		0.1		—		13.4
Total		$	541.3	$	1.2	$	—	$	542.5

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2026
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Clinical and Preclinical Development and Licensing Arrangements From time to time, the Company enters into contracts in the normal course of business with various third parties who support its clinical trials, preclinical research studies and other services related to its development activities. The scope of the services under these agreements can generally be modified at any time, and the agreement can be terminated by either party after a period of notice and receipt of written notice. In addition, under licensing and related arrangements to which the Company is a party, the Company may be obligated to make milestone payments to third parties. The payment obligations under these arrangements are contingent upon future events, such as achievement of specified milestones or generation of product sales, and the amount, timing and likelihood of such payments are not known. Yale University License Agreement In June 2024, the Company entered into an Amended and Restated License Agreement (the “Amended License Agreement”) with Yale pursuant to which the parties amended and restated the license agreement dated July 5, 2013, as amended to date (the "Original Agreement"). In connection with the signing of the Amended License Agreement, the Company made a payment of $14.95 million to Yale in June 2024, comprising both an upfront payment connected to the Amended License Agreement and an amount related to the collaboration income under the Novartis License Agreement and Novartis Asset Agreement (see Note 3, Research Collaboration and License Agreements, for a description of the agreements) and the Company made another $5.0 million payment to Yale in June 2025 on the first anniversary of signing. Thereafter, the Company will also pay to Yale (1) up to $15.0 million if it secures approval of the first and second royalty products (as defined in the Amended License Agreement), (2) a low single digit percentage royalty on certain, more narrowly defined “collaboration products,” and (3) a lower single digit royalty on its aggregate worldwide net sales of certain newly defined “meaningfully involved products.” The Company’s obligations under the Original Agreement to pay Yale minimum annual royalties and certain other annual fees have been eliminated and Yale has agreed to release all claims arising previously under the Original Agreement. Other provisions of the Original Agreement remain materially unchanged under the Amended License Agreement, including the requirement to pay to Yale a minimum license maintenance royalty totaling $0.1 million per year until the first sale to a third party of any licensed product, followed by success-based milestones for the first two licensed products for the development of the protein degradation technologies totaling approximately $3.0 million for the first licensed product and approximately $1.5 million for the second licensed product, certain of which milestones have already been satisfied, and low single-digit royalties on aggregate worldwide net sales of certain licensed products, which may be subject to reductions, and subject to minimum royalty payments that range from $0.2 million to $0.5 million.

Property, Equipment and Leasehold Improvements (Tables)

3 Months Ended

Mar. 31, 2026

Property, Plant and Equipment [Abstract]

Schedule of Property, Equipment and Leasehold Improvements

Property, equipment and leasehold improvements consist of the following:


(dollars in millions)	March 31, 2026		December 31, 2025
Laboratory equipment	$	21.7	$	21.3
Leasehold improvements	9.1		9.1
Office equipment	3.2		3.0
Total property, equipment and leasehold improvements	34.0		33.4
Less: accumulated depreciation and amortization	(28.5)		(28.2)
Property, equipment and leasehold improvements, net	$	5.5	$	5.2

Condensed Consolidated Statements of Changes in Stockholders' Equity (unaudited) - USD ($) shares in Millions, $ in Millions	Total	Common	Accumulated Deficit	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Treasury
Beginning balance (in shares) at Dec. 31, 2024		68.8
Beginning balance (in shares) at Dec. 31, 2024						0.0
Beginning balance at Dec. 31, 2024	$ 561.7	$ 0.1	$ (1,531.6)	$ 2,092.2	$ 1.0	$ 0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	15.0			15.0
Net (loss) income	82.9		82.9
Issuance of common stock under equity incentive plans (in shares)		0.8
Issuance of common stock for pre-funded warrants (in shares)		3.4
Unrealized gain (loss) on available-for-sale securities	0.5				0.5
Ending balance (in shares) at Mar. 31, 2025		73.0
Ending balance (in shares) at Mar. 31, 2025						0.0
Ending balance at Mar. 31, 2025	$ 660.1	$ 0.1	(1,448.7)	2,107.2	1.5	$ 0.0
Beginning balance (in shares) at Dec. 31, 2025	63.5	73.5
Beginning balance (in shares) at Dec. 31, 2025	10.0					10.0
Beginning balance at Dec. 31, 2025	$ 433.9	$ 0.1	(1,612.4)	2,136.9	1.2	$ (91.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	12.1			12.1
Net (loss) income	(57.6)		(57.6)
Issuance of common stock under equity incentive plans (in shares)		1.0
Unrealized gain (loss) on available-for-sale securities	$ (1.6)				(1.6)
Ending balance (in shares) at Mar. 31, 2026	64.5	74.5
Ending balance (in shares) at Mar. 31, 2026	10.0					10.0
Ending balance at Mar. 31, 2026	$ 386.8	$ 0.1	$ (1,670.0)	$ 2,149.0	$ (0.4)	$ (91.9)

- Definition

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

+ References

+ Details

- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

Segment Information (Tables)

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Schedule of Reportable Segment Financial Information

The following table summarizes the reportable segment's financial information:


	Three Months Ended March 31,
(dollars in millions)	2026		2025
Revenue	$	15.6	$	188.8
Less:
Research and development expense

Vepdegestrant (ARV-471) (*)	8.9		24.1
ARV-806	6.5		0.9
ARV-102	5.5		6.5

ARV-393	3.7		2.6
Bavdegalutamide (ARV-110)	0.2		1.1

Other programs	2.6		1.7

Non program-specific external expense	9.2		13.9

Compensation and related personnel expense (including stock-based compensation)	21.3		36.9
Other research and development expense	2.4		3.1

Total research and development expense	60.3		90.8
General and administrative expense	19.1		26.6
Other segment expense, net (**)	0.1		—
Income tax expense	0.1		0.2

Plus:
Interest income, net	6.4		11.7
Segment net (loss) income	$	(57.6)	$	82.9

(*) Includes net reimbursement to and from Pfizer pursuant to the Vepdegestrant (ARV-471) Collaboration Agreement which are accounted for pursuant to ASC 808 and are recorded as an offset or an increase to research and development expenses.

(**) Includes realized gains/ losses on foreign currency transactions and gains/ losses on sale of marketable securities.

Commitments and Contingencies (Details) - Yale University $ in Thousands		1 Months Ended
	Jul. 05, 2013 USD ($) product	Jun. 30, 2024 USD ($)
Maximum
Commitments And Contingencies [Line Items]
Royalty payment	$ 500
Minimum
Commitments And Contingencies [Line Items]
Annual payment for license	$ 100
Number of licensed products \| product	2
Royalty payment	$ 200
Upfront Payment for Amended License Agreement and Novartis License and Asset Agreements
Commitments And Contingencies [Line Items]
Payments for collaboration		$ 14,950
Milestone Payment on First Anniversary of Signing
Commitments And Contingencies [Line Items]
Milestone payment the Company will make		5,000
Milestone Payment Upon Approval of First and Second Royalty Products \| Maximum
Commitments And Contingencies [Line Items]
Milestone payment the Company will make		$ 15,000
Success-Based Milestone Payments \| License First Licensed Product
Commitments And Contingencies [Line Items]
Required milestone payments	3,000
Success-Based Milestone Payments \| License Second Licensed Product
Commitments And Contingencies [Line Items]
Required milestone payments	$ 1,500

Segment Information

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Segment Information

The Company's operations are organized into one operating and reportable segment focused on the discovery, development and commercialization of therapies that degrade disease-causing proteins. The segment develops protein degradation therapies designed to harness the body's natural protein disposal system to selectively and efficiently degrade and remove disease-causing protein through the Company's PROteolysis TArgeting Chimera (PROTAC) protein degrader platform.

In the second quarter of 2026, the Company announced that the FDA granted approval for VEPPANU™ (vepdegestrant) for the treatment of adults with ER+/HER2-, ESR1-mutated advanced or metastatic breast cancer, as detected by an FDA-authorized test, with disease progression following at least one line of endocrine-based therapy. VEPPANU is the first and only FDA-approved PROTAC protein degrader, a type of heterobifunctional protein degrader therapy.

The Company is also progressing multiple product candidates through clinical development programs, including ARV-102, targeting the leucine-rich repeat kinase 2 protein for the treatment of neurodegenerative diseases; ARV-806, targeting Kirsten rat sarcoma G12D protein for cancers with the G12D mutation, including pancreatic, colorectal and non-small cell lung cancers; ARV-393, targeting the B-cell lymphoma 6 protein for the treatment of relapsed/refractory non-Hodgkin Lymphoma; ARV-027, targeting the polyQ-AR in skeletal muscle for the treatment of Spinal-Bulbar Muscular Atrophy, or SBMA, also known as Kennedy's disease. The Company's tangible assets are held in the United States and all of the Company's revenue has been generated in the United States. The Company manages all business activities on a consolidated basis. The Company's chief operating decision maker is the Chief Executive Officer.

The operating segment's revenue is primarily generated through research collaborations and licensing arrangements with pharmaceutical partners. The terms of these agreements contain multiple goods and services which may include (i) licenses, (ii) research and development activities, and (iii) participation in joint research and development steering committees. The terms of these agreements may include non-refundable, upfront license or option fees, payments for research and development activities, payments upon the achievement of certain milestones and royalty payments based on product sales derived from the collaboration. Revenue is recognized ratably over the Company’s expected performance period under each respective arrangement. The Company also generated revenue through the sale of assets based on fair value. The Company does not have intra-entity sales or transfers.

The accounting policies of the operating segment are the same as those described in the Company's Annual Report on Form 10-K for the year ended December 31, 2025 and in Note 2, Summary of Accounting Pronouncements and Significant Accounting Policies. The chief operating decision maker evaluates the performance of the operating segment and allocates resources based on net income/loss that also is reported on the consolidated income statement as net (loss) income. The measure of the operating segment assets is reported on the consolidated balance sheet as total assets.

The chief operating decision maker uses net loss to monitor budget versus actual results and to analyze cash flows in assessing performance of the segment and allocating resources.

The following table summarizes the reportable segment's financial information:


	Three Months Ended March 31,
(dollars in millions)	2026		2025
Revenue	$	15.6	$	188.8
Less:
Research and development expense

Vepdegestrant (ARV-471) (*)	8.9		24.1
ARV-806	6.5		0.9
ARV-102	5.5		6.5

ARV-393	3.7		2.6
Bavdegalutamide (ARV-110)	0.2		1.1

Other programs	2.6		1.7

Non program-specific external expense	9.2		13.9

Compensation and related personnel expense (including stock-based compensation)	21.3		36.9
Other research and development expense	2.4		3.1

Total research and development expense	60.3		90.8
General and administrative expense	19.1		26.6
Other segment expense, net (**)	0.1		—
Income tax expense	0.1		0.2

Plus:
Interest income, net	6.4		11.7
Segment net (loss) income	$	(57.6)	$	82.9

(**) Includes realized gains/ losses on foreign currency transactions and gains/ losses on sale of marketable securities.

During each of the three months ended March 31, 2026 and 2025, the Company recognized depreciation and amortization expense of $0.7 million.

- 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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+ Details