0001640266-26-000006 | 10-Q | XBRL Viewer

General and administrative

Collaboration revenue

$ 3,165

$ 5,200

$ 5,758

$ 11,673

7,516

10,495

15,777

20,135

Interest income

1,528

2,831

3,440

6,122

Other income

411

427

846

845

Income tax provision

Net loss

(24,473)

$ (27,937)

(33,382)

$ (31,021)

(52,410)

(64,403)

Single reportable segment

Internal research and development

Collaboration revenue

3,165

5,200

5,758

11,673

^[1]

7,781

10,263

15,874

20,221

Facilities and other research and development

^[2]

5,204

7,852

11,329

15,939

General and administrative

^[2]

7,516

10,495

15,777

20,135

Interest income

1,528

2,831

3,440

6,122

Other income

411

427

846

845

Income tax provision

Net loss

(24,473)

(33,382)

(52,410)

(64,403)

Single reportable segment | Anti-tau antibody program (VY7523)

Single reportable segment | Tau silencing gene therapy program (VY1706)

^[3]

1,959

3,705

4,336

7,954

Single reportable segment | SOD1 silencing gene therapy program

^[3]

2,873

3,414

8,509

6,588

Single reportable segment | Partnered programs

^[3]

380

2,266

Single reportable segment | Other programs and platforms

^[3],[4]

1,787

1,898

2,459

2,889

Commitments and Contingencies Disclosure [Abstract]

^[3],[5]

$ 2,437

$ 3,818

$ 4,136

$ 6,999

[1]	Internal research and development consist of employee-related expenses, including salaries, benefits, and stock-based compensation expense.
[2]	Depreciation and amortization expense is allocated between general and administrative and facilities and other research and development.
[3]	External research and development is allocated to the Company’s programs and platforms and includes laboratory supplies and non-employee consultant and contractor costs.
[4]	Partnered programs include programs in which the Company is collaborating with partners to develop AAV gene therapy products and product candidates under the Company’s 2019 and 2023 Neurocrine Collaboration Agreements and the License and Collaboration Agreement the Company entered into with Novartis on December 28, 2023.
[5]	Other programs and platforms consist of expenses related to other early research programs and platforms that are not considered quantitatively and qualitatively significant, including capsid discovery, non-viral delivery, and early research programs.

Commitments, Contingencies and Other Liabilities

6 Months Ended

Jun. 30, 2026

Commitments, Contingencies, and Other Liabilities

7. Commitments, contingencies and other liabilities

Other Agreements

In 2016, the Company entered into a research and development funding arrangement with a non-profit organization that provided up to $4.0 million in funding to the Company upon the achievement of clinical and development milestones. The agreement, as amended in 2022, provides that the Company is obligated to repay amounts received under certain circumstances, including termination of the agreement, and to pay an amount up to 2.6 times the funding received upon successful development and commercialization of any products developed. In 2017, the Company earned a milestone payment of $1.0 million. The Company evaluated the arrangement and concluded that it represents a research and development financing arrangement as it is probable that the Company will repay amounts received under the arrangement. As a result, the $1.0 million is recorded as a non-current liability in the condensed consolidated balance sheet.

Litigation

The Company was not a party to any material legal matters or claims as of June 30, 2026 or December 31, 2025. The Company did not have contingency reserves established for any litigation liabilities as of June 30, 2026 or December 31, 2025.

Significant Agreements (Tables)

6 Months Ended

Jun. 30, 2026

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]


	Balance at								Balance at
	December 31, 2025			Additions		Deductions			June 30, 2026
		(in thousands)
Related party collaboration receivables	$		151	$	372	$	(301	)	$	222
Contract liabilities:
Deferred revenue	$		1,590	$	—	$	(1,346	)	$	244

Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Assets, Fair Value Disclosure
Cash and cash equivalents	$ 35,769	$ 65,300
Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Total cash equivalents and marketable securities	137,593	191,029
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Total cash equivalents and marketable securities	88,419	139,353
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Total cash equivalents and marketable securities	49,174	51,676
Money Market Funds
Assets, Fair Value Disclosure
Cash and cash equivalents	24,548	51,161
Money Market Funds \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Cash and cash equivalents	24,548	51,161
Money Market Funds \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Cash and cash equivalents	24,548	51,161
U.S. Treasury Notes \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Marketable securities	39,931	72,805
U.S. Treasury Notes \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Marketable securities	39,931	72,805
U.S. Government Agency Securities \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Marketable securities	23,940	15,387
U.S. Government Agency Securities \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Marketable securities	23,940	15,387
Corporate Bonds \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Marketable securities	43,371	44,260
Corporate Bonds \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Marketable securities	43,371	44,260
Commercial Paper
Assets, Fair Value Disclosure
Cash and cash equivalents		3,477
Commercial Paper \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Cash and cash equivalents		3,477
Marketable securities	5,803	3,939
Commercial Paper \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Cash and cash equivalents		3,477
Marketable securities	$ 5,803	$ 3,939

Stock-based Compensation - Summary of Status and Changes in Unvested Restricted Stock and Performance-based Restricted Stock Units (Details) - Unvested RSUs and PRSUs	6 Months Ended
	Jun. 30, 2026 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Balance, beginning (in shares) \| shares	2,296,920
Granted (in shares) \| shares	797,398
Vested (in shares) \| shares	(600,929)
Forfeited (in shares) \| shares	(578,021)
Balance, ending (in shares) \| shares	1,915,368
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Balance, beginning (in dollars per share) \| $ / shares	$ 5.39
Granted (in dollars per share) \| $ / shares	3.71
Vested (in dollars per share) \| $ / shares	6.18
Forfeited (in dollars per share) \| $ / shares	5.39
Balance, ending (in dollars per share) \| $ / shares	$ 4.44

Lease Obligation - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)	Feb. 01, 2024 USD ($)	Aug. 01, 2023 ft²
Lessee, Lease, Description [Line Items]
Restricted cash included in deposits and other non-current assets	$ 2,736		$ 2,736		$ 2,736
Lease expense	$ 1,800	$ 1,900	$ 3,700	$ 3,800
Weighted average remaining lease term	3 years 2 months 12 days		3 years 2 months 12 days
Weighted average incremental borrowing rate	6.50%		6.50%
Lexington Facility
Lessee, Lease, Description [Line Items]
Area of additional facility leased \| ft²							61,307
Expected contractual obligation for lease not yet commenced						$ 35,400
Lease term						7 years
Restricted cash included in deposits and other non-current assets	$ 2,700		$ 2,700

Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

Significant agreements - Schedule of Schedule of Related Party Collaboration Receivable and Deferred Revenue (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2026 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Related party collaboration receivables, beginning balance	$ 151
Related party collaboration receivables, ending balance	222
2023 Neurocrine Collaboration Agreement and 2019 Neurocrine Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Related party collaboration receivables, beginning balance	151
Additions	372
Deductions	(301)
Related party collaboration receivables, ending balance	222
Deferred revenue, beginning balance	1,590
Deductions	(1,346)
Deferred revenue, ending balance	$ 244

Lease Obligation - Future Minimum Lease Payments Due Under Operating Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Total minimum lease payments
Remainder of 2026	$ 4,908
2027	7,763
2028	7,996
2029	8,235
2030	8,483
Thereafter	227
Total future minimum lease payments	37,612
Less: imputed interest	(5,045)
Total operating lease liabilities	32,567
Operating lease liabilities	6,876	$ 7,840
Operating lease liabilities, net of current portion	$ 25,691	$ 28,659

Lease Obligation - Operating Sublease Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Leases [Abstract]
Operating sublease income	$ 402	$ 303	$ 804	$ 606

Fair Value Measurements

6 Months Ended

Jun. 30, 2026

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair value measurements

Assets and liabilities measured at fair value on a recurring basis as of June 30, 2026 and December 31, 2025, are as follows:


			Quoted Prices		Significant
			in Active		Other		Significant
			Markets for		Observable		Unobservable
			Identical Assets		Inputs		Inputs
Assets	Total		(Level 1)		(Level 2)		(Level 3)
June 30, 2026	(in thousands)
Cash equivalents:
Money market funds	$	24,548	$	24,548	$	—	$	—
Marketable securities:
U.S. Treasury notes		39,931		39,931		—		—
U.S. Government agency securities		23,940		23,940		—		—
Corporate bonds		43,371		—		43,371		—
Commercial paper		5,803		—		5,803		—
Total cash equivalents and marketable securities	$	137,593	$	88,419	$	49,174	$	—
December 31, 2025
Cash equivalents:
Money market funds	$	51,161	$	51,161	$	—	$	—
Commercial paper		3,477		—		3,477		—
Marketable securities:
U.S. Treasury notes		72,805		72,805		—		—
U.S. Government agency securities		15,387		15,387		—		—
Corporate bonds		44,260		—		44,260		—
Commercial paper		3,939		—		3,939		—
Total cash equivalents and marketable securities	$	191,029	$	139,353	$	51,676	$	—

The Company measures the fair value of money market funds, U.S. Treasury notes and U.S. Government agency securities based on quoted prices in active markets for identical securities. The Company measures the fair value of the Level 2 securities, including corporate bonds and commercial paper, based on recent trades of securities in inactive markets or based on quoted market prices of similar instruments and other significant inputs derived from or corroborated by observable market data.

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.

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Cash Equivalents and Available-for-Sale Marketable Securities - Additional Information (Details) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2026 USD ($) Item	Dec. 31, 2025 USD ($) Item
Cash Equivalents and Available-for-Sale Marketable Securities [Line Items]
Number of marketable securities \| Item	58	20
Debt securities, unrealized loss position \| $	$ 74.5	$ 26.6
Maximum
Cash Equivalents and Available-for-Sale Marketable Securities [Line Items]
Debt securities, contractual maturity period	2 years	2 years

Stock-based Compensation - Summary of Compensation Cost Recognized for All Stock-based Compensation Awards (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation	$ 2,433	$ 4,133	$ 4,921	$ 7,806
Location, Statement of Income, Balance [Axis]: us-gaap:GeneralAndAdministrativeExpense
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation	1,305	2,504	3,133	4,692
Location, Statement of Income, Balance [Axis]: us-gaap:ResearchAndDevelopmentExpense
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation	$ 1,128	$ 1,629	$ 1,788	$ 3,114

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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-Paragraph 2
-Subparagraph (c)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(02)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Related-Party Transactions - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Related-party transactions
Collaboration revenue	$ 3,165	$ 5,200	$ 5,758	$ 11,673
Dr. Sah \| Related Party
Related-party transactions
Total amount of services received	200	100	300	300
2019 and 2023 Neurocrine Collaboration Agreement \| Neurocrine \| Related Party
Related-party transactions
Collaboration revenue	$ 400	$ 3,700	$ 1,800	$ 8,600

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
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-Name Accounting Standards Codification
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-Paragraph 1
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15)(4))
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-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15)(3))
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 970
-SubTopic 810
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477383/970-810-45-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-3

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
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-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-13

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(i))
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-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

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.

Nature of Business - Additional Information (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ (498,315)	$ (445,905)
Cash, cash equivalents, and marketable securities	$ 148,800

Amount of accumulated undistributed earnings (deficit).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 4
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-URI https://asc.fasb.org/1943274/2147480100/505-10-S45-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Section S99
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480016/944-40-65-2

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (h)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480016/944-40-65-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-11

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(a)(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(17))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1

Summary of Operating Sublease Income

Lease Obligation (Tables)

6 Months Ended

Jun. 30, 2026

Leases [Abstract]

The following table summarizes the operating sublease income generated under the Sublease Agreement for the three and six months ended June 30, 2026 and 2025:


	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2026			2025		2026			2025
		(in thousands)					(in thousands)
Operating sublease income	$		402	$	303	$		804	$	606

Summary of Future Minimum Lease Payments Due Under Operating Leases

Future minimum lease payments due under operating leases are as follows:


	Total Minimum
Year Ending December 31,	Lease Payments
	(in thousands)
Remainder of 2026	$	4,908
2027		7,763
2028		7,996
2029		8,235
2030		8,483
Thereafter		227
Total future minimum lease payments	$	37,612
Less: imputed interest		(5,045	)
Total operating lease liabilities	$	32,567
Reported as:
Operating lease liabilities	$	6,876
Operating lease liabilities, net of current portion		25,691
Total operating lease liabilities	$	32,567

Significant agreements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue	$ 3,165	$ 5,200	$ 5,758	$ 11,673
2023 Neurocrine Collaboration Agreement and 2019 Neurocrine Collaboration Agreement \| Neurocrine \| FA Program and Discovery Program 3
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue recognized			$ 1,300

Share-Based Payment Arrangement [Abstract]

Net Loss Per Share

6 Months Ended

Jun. 30, 2026

Earnings Per Share [Abstract]

Net loss per share

10. Net loss per share

For purposes of the diluted net loss per share, unvested restricted common stock awards, unvested RSUs and PRSUs, and outstanding stock options are considered to be potentially dilutive securities. Unvested RSUs and PRSUs and outstanding stock options were excluded from the calculation of diluted net loss per share in the three and six months ended June 30, 2026 and 2025, because their effect would be anti-dilutive and therefore, basic and diluted net loss per share were the same for the three and six months ended June 30, 2026 and 2025.

The following table sets forth the outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because to include them would be anti-dilutive:


	As of June 30,
	2026		2025
Unvested RSUs and PRSUs		1,915,368		2,726,298
Outstanding stock options		10,089,854		10,345,167
Total		12,005,222		13,071,465

Stock-based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2026 USD ($) $ / shares shares	Dec. 31, 2025 USD ($) $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning balance (in shares) \| shares	9,613,881
Granted (in shares) \| shares	2,650,700
Exercised (in shares) \| shares	(192,931)
Cancelled or forfeited (in shares) \| shares	(1,981,796)
Outstanding, ending balance (in shares) \| shares	10,089,854	9,613,881
Exercisable (in shares) \| shares	6,268,111
Weighted Average Exercise Price
Outstanding (in dollars per share) \| $ / shares	$ 7.26
Granted (in dollars per share) \| $ / shares	3.69
Exercised (in dollars per share) \| $ / shares	3.13
Cancelled or forfeited (in dollars per share) \| $ / shares	7.25
Outstanding (in dollars per share) \| $ / shares	6.41	$ 7.26
Exercisable (in dollars per share) \| $ / shares	$ 7.52
Remaining Contractual Life
Outstanding	7 years 1 month 6 days	6 years 9 months 18 days
Exercisable	6 years
Aggregate Intrinsic Value
Outstanding \| $	$ 596	$ 1,251
Exercisable \| $	$ 534

Stock-based Compensation

6 Months Ended

Jun. 30, 2026

Stock-based Compensation

9. Stock‑based compensation

Stock‑Based Compensation Expense

Total compensation cost recognized for all stock‑based compensation awards in the condensed consolidated statements of operations and comprehensive loss was as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
	(in thousands)
Research and development	$	1,128	$	1,629	$	1,788	$	3,114
General and administrative		1,305		2,504		3,133		4,692
Total stock-based compensation expense	$	2,433	$	4,133	$	4,921	$	7,806

Employee Stock Purchase Plan

In October 2015, the Company’s board of directors (the “Board”) and stockholders approved the 2015 Employee Stock Purchase Plan (the “2015 ESPP”). Under the 2015 ESPP, all full-time employees of the Company are eligible to purchase common stock of the Company twice per year, at the end of each six-month payment period. During each payment period, eligible employees who so elect, may authorize payroll deductions in an amount of 1% to 10% (whole percentages only) of the employee’s base pay for each payroll period. At the end of each payment period, the accumulated deductions are used to purchase shares of common stock from the Company at a discount. A total of 262,362 shares of common stock were initially authorized for issuance under the 2015 ESPP.

On March 18, 2025, the Board adopted, and on June 3, 2025, the stockholders approved, the Amended and Restated 2015 Employee Stock Purchase Plan (together with the 2015 ESPP, the “ESPP”) to (i) eliminate the evergreen provision in the 2015 ESPP and (ii) expand the class of eligible employees by eliminating the requirement that participants must have completed six months of employment.

As of June 30, 2026, there were 1,736,020 shares available for future purchase under the ESPP.

2025 Stock Incentive Plan

On March 18, 2025, the Board adopted, and on June 3, 2025, the stockholders approved, the 2025 Stock Incentive Plan (the “2025 Plan”). Under the 2025 Plan, the Company may issue awards for up to a number of shares of common stock equal to the sum of: (i) 3,631,952 shares of common stock; and (ii) such additional number of shares of common stock (up to 14,190,976 shares) as is equal to the sum of (x) the number of shares of common stock reserved for issuance under the Company’s 2015 Stock Option and Incentive Plan (the “2015 Plan”) that remained available for grant thereunder immediately prior to the date that the 2025 Plan was approved by our stockholders and (y) the number of shares of common stock subject to awards granted under the 2015 Plan that were

outstanding as of the date that the 2025 Plan was approved by our stockholders and which awards expire, terminate or are otherwise surrendered, cancelled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right (subject, however, in the case of incentive stock options, to any limitations under the Internal Revenue Code of 1986, as amended, and any regulations thereunder).

The Company intends to utilize the 2025 Plan to grant equity awards to the Company’s employees, non-employee directors, consultants, and advisors in order to recruit, incentivize, retain and reward those who are critical to the Company’s success. No new awards will be granted under the 2015 Plan.

As of June 30, 2026, there were 5,335,281 shares available under the 2025 Plan.

Restricted Stock Units and Performance Restricted Stock Units

A summary of the status of and changes in unvested restricted stock unit (“RSU”) activity and performance-based restricted stock unit (“PRSU”) activity under the Company’s equity award plans for the six months ended June 30, 2026, was as follows:


				Weighted Average Grant
	Units			Date Fair Value Per Unit
Unvested as of December 31, 2025		2,296,920		$	5.39
Granted		797,398			3.71
Vested		(600,929	)		6.18
Forfeited		(578,021	)		5.39
Outstanding as of June 30, 2026		1,915,368		$	4.44

All RSUs granted during the six months ended June 30, 2026, vest in equal amounts, annually over three years. Stock-based compensation for RSUs is based on the fair value of the Company’s common stock on the date of grant and is recognized over the vesting period.

As of June 30, 2026, the Company had unrecognized stock-based compensation expense related to its unvested RSUs (excluding PRSUs) of $5.0 million, which is expected to be recognized over the remaining average vesting period of 2.0 years.

During the first quarter of 2025, in connection with the Company’s annual compensation cycle, the Company granted PRSUs to members of the Company’s senior leadership team to more closely align with long-term performance incentives. The awards vest as to a certain number of PRSUs upon the achievement of specified clinical performance milestones over multiple years. Stock-based compensation for PRSUs is based on the fair value of the Company’s common stock on the date of grant and will be recognized at the time the achievement of the specified performance milestones becomes probable. The Company did not recognize any stock-based compensation expense in connection with the PRSUs during the six months ended June 30, 2026.

As of June 30, 2026, the Company had unrecognized stock-based compensation expense related to its unvested PRSUs of $2.0 million. The Company will recognize a cumulative catch-up adjustment in the period in which the specified performance condition is considered probable.

Stock Options

The following is a summary of stock option activity for the six months ended June 30, 2026:


				Weighted		Remaining		Aggregate
				Average		Contractual		Intrinsic Value
	Shares			Exercise Price		Life (in years)		(in thousands)
Outstanding as of December 31, 2025		9,613,881		$	7.26		6.8	$	1,251
Granted		2,650,700			3.69
Exercised		(192,931	)		3.13
Cancelled or forfeited		(1,981,796	)		7.25
Outstanding as of June 30, 2026		10,089,854		$	6.41		7.1	$	596
Exercisable as of June 30, 2026		6,268,111		$	7.52		6.0	$	534

As of June 30, 2026, the Company had unrecognized stock-based compensation expense related to its unvested stock options of $11.1 million, which is expected to be recognized over the remaining weighted-average vesting period of 2.5 years.

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2026	Jul. 30, 2026
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2026
Document Transition Report	false
Entity File Number	001-37625
Entity Registrant Name	Voyager Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-3003182
Entity Address, Address Line One	75 Hayden Avenue
Entity Address, City or Town	Lexington
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02421
City Area Code	857
Local Phone Number	259-5340
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	VYGR
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		61,617,948
Entity Central Index Key	0001640266
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q2
Amendment Flag	false

Segment Information

6 Months Ended

Jun. 30, 2026

Segment Reporting [Abstract]

Segment Information

12. Segment Information

The Company’s Chief Operating Decision Maker (“CODM”), the Company’s Chief Executive Officer, views the Company’s operations and manages its business as a single operating segment, which is the business of developing and commercializing genetic medicines. The Company therefore has one reportable segment.

The CODM reviews the segment’s profit or loss based on net loss reported on the condensed consolidated statement of operations and comprehensive loss and considers forecast-to-actual variances quarterly for expenses that are deemed significant in making resource allocation decisions and assessing performance. Further, the CODM reviews the segment’s assets based on total assets reported on the condensed consolidated balance sheets. All long-lived assets are held in the United States.

The CODM views specific categories within research and development expenses and general and administrative expenses in totality as significant. Further, the CODM views the external research and development expenses of specific programs as significant given the impact on achieving the Company’s corporate goals. The following table reconciles reported collaboration revenue and segment expenses to net loss under the significant expense principle for the three and six months ended June 30, 2026 and 2025:


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2026			2025			2026			2025
Collaboration revenue	$	3,165		$	5,200		$	5,758		$	11,673
External research and development (1):
Anti-tau antibody program (VY7523)		1,959			3,705			4,336			7,954
Tau silencing gene therapy program (VY1706)		2,873			3,414			8,509			6,588
SOD1 silencing gene therapy program		—			380			—			2,266
Partnered programs (2)		1,787			1,898			2,459			2,889
Other programs and platforms (3)		2,437			3,818			4,136			6,999
Internal research and development (4)		7,781			10,263			15,874			20,221
Facilities and other research and development (5)		5,204			7,852			11,329			15,939
General and administrative (5)		7,516			10,495			15,777			20,135
Interest income		1,528			2,831			3,440			6,122
Other income		411			427			846			845
Income tax provision		20			15			34			52
Net loss	$	(24,473	)	$	(33,382	)	$	(52,410	)	$	(64,403	)

(1)

External research and development is allocated to the Company’s programs and platforms and includes laboratory supplies and non-employee consultant and contractor costs.

(2)

Partnered programs include programs in which the Company is collaborating with partners to develop AAV gene therapy products and product candidates under the Company’s 2019 and 2023 Neurocrine Collaboration Agreements and the License and Collaboration Agreement the Company entered into with Novartis on December 28, 2023.

(3)

Other programs and platforms consist of expenses related to other early research programs and platforms that are not considered quantitatively and qualitatively significant, including capsid discovery, non-viral delivery, and early research programs.

(4)

Internal research and development consist of employee-related expenses, including salaries, benefits, and stock-based compensation expense.

(5)

Depreciation and amortization expense is allocated between general and administrative and facilities and other research and development.

The entire disclosure for segment reporting.

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Schedule of Accrued Expenses

Accrued Expenses (Tables)

6 Months Ended

Jun. 30, 2026

Payables and Accruals [Abstract]

Accrued expenses as of June 30, 2026 and December 31, 2025, consist of the following:


	As of June 30,		As of December 31,
	2026		2025
	(in thousands)
Employee compensation costs	$	4,108	$	9,091
Research and development costs		2,655		2,069
Accrued other		628		549
Professional services		560		389
Total	$	7,951	$	12,098

Stock-based Compensation - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Oct. 31, 2015	Jun. 30, 2026	Jun. 03, 2025
RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period		3 years
Unrecognized stock-based compensation expense		$ 5.0
Remaining weighted-average remaining vesting period		2 years
PRSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized stock-based compensation expense		$ 2.0
Employee Stock Option Member
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized stock-based compensation expense		$ 11.1
Remaining weighted-average remaining vesting period		2 years 6 months
2015 Employee Stock Purchase Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Period to purchase shares	6 months
Number of shares authorized for stock-based compensation plan (in shares)	262,362
Shares available for future issuance (in shares)		1,736,020
2015 Employee Stock Purchase Plan \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage of payroll deduction	10.00%
2015 Employee Stock Purchase Plan \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage of payroll deduction	1.00%
2025 Stock Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares authorized for stock-based compensation plan (in shares)		5,335,281
Maximum shares authorized excluding shares reserved under previous plan			3,631,952
Shares reserved under previous plan			14,190,976

Net Loss Per Share - Schedule of outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share (Details) - shares	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities	12,005,222	13,071,465
Unvested RSUs and PRSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities	1,915,368	2,726,298
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities	10,089,854	10,345,167

Summary of Significant Accounting Policies and Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2026
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial reporting. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. For further information, refer to the consolidated financial statements and footnotes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025, as filed with the Securities and Exchange Commission on March 9, 2026. These interim condensed consolidated financial statements, in the opinion of management, reflect all normal recurring adjustments necessary for a fair presentation of the Company’s financial position and results of operations for the periods presented. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP, which can be found in the Accounting Standards Codification and Accounting Standards Updates of the Financial Accounting Standards Board.
Principles of Consolidation	Principles of Consolidation The unaudited interim condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary as disclosed in Note 2, Summary of Significant Accounting Policies and Basis of Presentation, within the “Notes to Consolidated Financial Statements” accompanying the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025. Intercompany balances and transactions have been eliminated.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. On an ongoing basis, the Company’s management evaluates its estimates, which include, but are not limited to, estimates related to revenue recognition, research and development accrued expenses, stock‑based compensation expense, and income taxes. The Company bases its estimates on historical experience and other market-specific or other relevant assumptions that it believes to be reasonable under the circumstances. Actual results may differ from those estimates or assumptions.
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies There have been no changes in the Company’s significant accounting policies as described in Note 2, Summary of Significant Accounting Policies and Basis of Presentation, within the “Notes to Consolidated Financial Statements” accompanying the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025.

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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Accrued Liabilities, Current [Abstract]

Cash Equivalents and Available-for-Sale Marketable Securities - Schedule of Cash Equivalents and Available-for-Sale Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Amortized Cost
Cash and cash equivalents	$ 35,769	$ 65,300
Total cash equivalents and marketable securities	137,886	190,869
Unrealized Gains and Losses
Marketable securities, Unrealized Gains	17	178
Unrealized Losses, Less than 12 months - Marketable securities	(66)	(11)
Unrealized Losses, Greater than 12 months - Marketable securities	(244)	(7)
Fair Value
Total money market funds and marketable securities	137,593	191,029
Money Market Funds
Amortized Cost
Cash and cash equivalents	24,548	51,161
Fair Value
Cash and cash equivalents, Fair Value	24,548	51,161
U.S. Treasury Notes
Amortized Cost
Marketable securities, Amortized Cost	40,002	72,665
Unrealized Gains and Losses
Marketable securities, Unrealized Gains	15	141
Unrealized Losses, Less than 12 months - Marketable securities	(3)	(1)
Unrealized Losses, Greater than 12 months - Marketable securities	(83)
Fair Value
Marketable securities, Fair Value	39,931	72,805
U.S. Government Agency Securities
Amortized Cost
Marketable securities, Amortized Cost	24,067	15,376
Unrealized Gains and Losses
Marketable securities, Unrealized Gains		18
Unrealized Losses, Less than 12 months - Marketable securities	(17)
Unrealized Losses, Greater than 12 months - Marketable securities	(110)	(7)
Fair Value
Marketable securities, Fair Value	23,940	15,387
Corporate Bonds
Amortized Cost
Marketable securities, Amortized Cost	43,466	44,251
Unrealized Gains and Losses
Marketable securities, Unrealized Gains	2	19
Unrealized Losses, Less than 12 months - Marketable securities	(46)	(10)
Unrealized Losses, Greater than 12 months - Marketable securities	(51)
Fair Value
Marketable securities, Fair Value	43,371	44,260
Commercial Paper
Amortized Cost
Cash and cash equivalents		3,477
Marketable securities, Amortized Cost	5,803	3,939
Fair Value
Cash and cash equivalents, Fair Value		3,477
Marketable securities, Fair Value	$ 5,803	$ 3,939

Accrued Expenses

6 Months Ended

Jun. 30, 2026

Accrued Expenses

5. Accrued expenses

Accrued expenses as of June 30, 2026 and December 31, 2025, consist of the following:


	As of June 30,		As of December 31,
	2026		2025
	(in thousands)
Employee compensation costs	$	4,108	$	9,091
Research and development costs		2,655		2,069
Accrued other		628		549
Professional services		560		389
Total	$	7,951	$	12,098

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 35,769	$ 65,300
Marketable securities	80,569	131,147
Accounts receivable	2,932	1,761
Related party collaboration receivable	222	151
Prepaid expenses and other current assets	5,736	4,328
Total current assets	125,228	202,687
Property and equipment, net	11,194	13,136
Restricted cash	2,736	2,736
Marketable securities, non-current	32,476	5,244
Other non-current assets	214
Operating lease, right-of-use assets	25,905	28,478
Total assets	197,753	252,281
Current liabilities:
Accounts payable	1,614	5,013
Accrued expenses	7,951	12,098
Operating lease liabilities	6,876	7,840
Deferred revenue	244	1,590
Total current liabilities	16,685	26,541
Operating lease liabilities, net of current portion	25,691	28,659
Other non-current liabilities	1,000	1,000
Total liabilities	43,376	56,200
Commitments, contingencies, and other liabilities (see note 7)
Stockholders' equity:
Preferred stock, $0.001 par value: 5,000,000 shares authorized at June 30, 2026 and December 31, 2025; no shares issued and outstanding at June 30, 2026 and December 31, 2025
Common stock, $0.001 par value: 240,000,000 and 120,000,000 shares authorized at June 30, 2026 and December 31, 2025, respectively; 61,273,390 and 59,047,860 shares issued and outstanding at June 30, 2026 and December 31, 2025, respectively	61	59
Additional paid-in capital	653,052	641,895
Accumulated other comprehensive (loss) income	(421)	32
Accumulated deficit	(498,315)	(445,905)
Total stockholders' equity	154,377	196,081
Total liabilities and stockholders' equity	$ 197,753	$ 252,281

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Income Statement [Abstract]
Collaboration revenue	$ 3,165	$ 5,200	$ 5,758	$ 11,673
Operating expenses:
Research and development	22,041	31,330	46,643	62,856
General and administrative	7,516	10,495	15,777	20,135
Total operating expenses	29,557	41,825	62,420	82,991
Operating loss	(26,392)	(36,625)	(56,662)	(71,318)
Other income, net:
Interest income	1,528	2,831	3,440	6,122
Other income	411	427	846	845
Total other income, net	1,939	3,258	4,286	6,967
Loss before income taxes	(24,453)	(33,367)	(52,376)	(64,351)
Income tax provision	20	15	34	52
Net loss	(24,473)	(33,382)	(52,410)	(64,403)
Other comprehensive (loss) income:
Net unrealized (loss) gain on available-for-sale securities	(158)	(22)	(453)	186
Total other comprehensive (loss) income	(158)	(22)	(453)	186
Comprehensive loss	$ (24,631)	$ (33,404)	$ (52,863)	$ (64,217)
Net loss per share, basic (in dollars per share)	$ (0.4)	$ (0.57)	$ (0.87)	$ (1.1)
Net loss per share, diluted (in dollars per share)	$ (0.4)	$ (0.57)	$ (0.87)	$ (1.1)
Weighted-average common shares outstanding, basic (in shares)	60,547,863	58,666,460	60,025,001	58,508,989
Weighted-average common shares outstanding, diluted (in shares)	60,547,863	58,666,460	60,025,001	58,508,989

Significant Agreements

6 Months Ended

Jun. 30, 2026

Significant Agreements [Abstract]

Significant Agreements

8. Significant agreements

The Company’s significant agreements are described in Note 9, Significant Agreements, within the “Notes to Consolidated Financial Statements” accompanying the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025. During the three and six months ended June 30, 2026, there were no material changes to the Company’s collaboration agreements or option and license agreements, and the Company did not enter into any new material collaboration or license agreements. The Company recorded collaboration revenue of $3.2 million and $5.2 million during the three months ended June 30, 2026 and 2025, respectively. The Company recorded collaboration revenue of $5.8 million and $11.7 million during the six months ended June 30, 2026 and 2025, respectively.

Related Party Collaboration Receivable and Deferred Revenue

The following table presents changes in the balances of the Company’s related party collaboration receivable and contract liabilities (reflected as deferred revenue in the condensed consolidated balance sheets) for the collaboration and license agreement the Company entered into with Neurocrine in January 2023 (the “2023 Neurocrine Collaboration Agreement”) and the collaboration and license agreement the Company entered into with Neurocrine in January 2019 (the “2019 Neurocrine Collaboration Agreement”) during the six months ended June 30, 2026:


	Balance at								Balance at
	December 31, 2025			Additions		Deductions			June 30, 2026
		(in thousands)
Related party collaboration receivables	$		151	$	372	$	(301	)	$	222
Contract liabilities:
Deferred revenue	$		1,590	$	—	$	(1,346	)	$	244

The change in the related party collaboration receivable balance for the six months ended June 30, 2026, is primarily driven by amounts owed to the Company for research and development services provided, offset by amounts collected during the period, under the 2023 and 2019 Neurocrine Collaboration Agreements. Deferred revenue activity for the six months ended June 30, 2026, includes the recording of $1.3 million of collaboration revenue recognized on the proportional performance model during the period for the 2023 and 2019 Neurocrine Collaboration Agreements.

Lease Obligation

6 Months Ended

Jun. 30, 2026

Leases [Abstract]

Lease Obligation

6. Lease obligation

Operating Leases

As of June 30, 2026, the Company has a lease for laboratory and office space at 75 Hayden Avenue in Lexington, Massachusetts (the “Lexington Facility”) through January 31, 2031, and a lease for additional office and laboratory space at 64 Sidney Street in Cambridge, Massachusetts (the “Cambridge Facility”) through November 30, 2026.

In August 2023, the Company entered into a first amendment (the “First Amendment”) to its existing lease for the Lexington Facility, pursuant to which the Company agreed to lease approximately 61,307 square feet of additional office and laboratory space. The commencement date for the First Amendment occurred on February 1, 2024. The expected contractual obligation under the First Amendment to the Company’s existing lease for the Lexington Facility is approximately $35.4 million, to be paid over the 7-year term of the lease.

The Company’s lease agreements require the Company to maintain a cash deposit or irrevocable letter of credit in the aggregate amount of $2.7 million payable to its landlords as security for the performance of its obligations under the leases. These amounts are recorded as restricted cash in the accompanying condensed consolidated balance sheets.

In August 2024, the Company executed the sublease of the Cambridge Facility (the “Sublease Agreement”). Payments received under the Sublease Agreement are included in other income in the condensed consolidated statements of operations and comprehensive (loss) income. Subject to certain conditions set forth therein, the Sublease Agreement terminates simultaneously with the Company’s lease for the Cambridge Facility.

Operating lease cost was $1.8 million and $1.9 million during the three months ended June 30, 2026 and 2025, respectively. Operating lease cost was $3.7 million and $3.8 million during the six months ended June 30, 2026 and 2025, respectively. As of June 30, 2026, the weighted-average remaining lease term was 3.2 years and the weighted-average incremental borrowing rate used to determine the operating lease liability was 6.5%.

The following table summarizes the operating sublease income generated under the Sublease Agreement for the three and six months ended June 30, 2026 and 2025:


	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2026			2025		2026			2025
		(in thousands)					(in thousands)
Operating sublease income	$		402	$	303	$		804	$	606

Future minimum lease payments due under operating leases are as follows:


	Total Minimum
Year Ending December 31,	Lease Payments
	(in thousands)
Remainder of 2026	$	4,908
2027		7,763
2028		7,996
2029		8,235
2030		8,483
Thereafter		227
Total future minimum lease payments	$	37,612
Less: imputed interest		(5,045	)
Total operating lease liabilities	$	32,567
Reported as:
Operating lease liabilities	$	6,876
Operating lease liabilities, net of current portion		25,691
Total operating lease liabilities	$	32,567

Cash Equivalents and Available-for-Sale Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2026

Cash and Cash Equivalents [Abstract]

Schedule of Cash Equivalents and Available-for-Sale Marketable Securities

Cash equivalents and available-for-sale marketable securities included the following as of June 30, 2026 and December 31, 2025:


					Unrealized Losses
	Amortized Cost		Unrealized Gains		Less than 12 months			Greater than 12 months			Fair Value
	(in thousands)
As of June 30, 2026
Cash equivalents:
Money market funds	$	24,548	$	—	$	—		$	—		$	24,548
Marketable securities:
U.S. Treasury notes		40,002		15		(3	)		(83	)		39,931
U.S. Government agency securities		24,067		—		(17	)		(110	)		23,940
Corporate bonds		43,466		2		(46	)		(51	)		43,371
Commercial paper		5,803		—		—			—			5,803
Total cash equivalents and marketable securities	$	137,886	$	17	$	(66	)	$	(244	)	$	137,593
As of December 31, 2025
Cash equivalents:
Money market funds	$	51,161	$	—	$	—		$	—		$	51,161
Commercial paper		3,477		—		—			—			3,477
Marketable securities:
U.S. Treasury notes		72,665		141		(1	)		—			72,805
U.S. Government agency securities		15,376		18		—			(7	)		15,387
Corporate bonds		44,251		19		(10	)		—			44,260
Commercial paper		3,939		—		—			—			3,939
Total cash equivalents and marketable securities	$	190,869	$	178	$	(11	)	$	(7	)	$	191,029

Schedule of Reconciliation of Cash, Cash Equivalents, and Restricted Cash

The following table provides a reconciliation of cash, cash equivalents, and restricted cash within the condensed consolidated balance sheets that sum to the total of the same amounts shown in the condensed consolidated statements of cash flows:


	As of June 30,		As of December 31,
	2026		2025
	(in thousands)
Cash and cash equivalents	$	35,769	$	65,300
Restricted cash included in deposits and other non-current assets		2,736		2,736
Total cash, cash equivalents, and restricted cash	$	38,505	$	68,036

Commitments, Contingencies and Other Liabilities - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) Multiple	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2017 USD ($)
Commitments Contingencies and Other Liabilities
Contingency reserves for litigation liabilities		$ 0.0	$ 0.0
Non-profit organization agreement
Commitments Contingencies and Other Liabilities
Maximum funding	$ 4.0
Funding multiple \| Multiple	2.6
Milestone payment liability				$ 1.0

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Accrued Liabilities, Current [Abstract]
Employee compensation costs	$ 4,108	$ 9,091
Research and development costs	2,655	2,069
Accrued other	628	549
Professional services	560	389
Total	$ 7,951	$ 12,098

Cash Equivalents and Available-for-Sale Marketable Securities

6 Months Ended

Jun. 30, 2026

Cash and Cash Equivalents [Abstract]

Cash Equivalents and Available-for-Sale Marketable Securities

4. Cash equivalents and available-for-sale marketable securities

Cash equivalents and available-for-sale marketable securities included the following as of June 30, 2026 and December 31, 2025:


					Unrealized Losses
	Amortized Cost		Unrealized Gains		Less than 12 months			Greater than 12 months			Fair Value
	(in thousands)
As of June 30, 2026
Cash equivalents:
Money market funds	$	24,548	$	—	$	—		$	—		$	24,548
Marketable securities:
U.S. Treasury notes		40,002		15		(3	)		(83	)		39,931
U.S. Government agency securities		24,067		—		(17	)		(110	)		23,940
Corporate bonds		43,466		2		(46	)		(51	)		43,371
Commercial paper		5,803		—		—			—			5,803
Total cash equivalents and marketable securities	$	137,886	$	17	$	(66	)	$	(244	)	$	137,593
As of December 31, 2025
Cash equivalents:
Money market funds	$	51,161	$	—	$	—		$	—		$	51,161
Commercial paper		3,477		—		—			—			3,477
Marketable securities:
U.S. Treasury notes		72,665		141		(1	)		—			72,805
U.S. Government agency securities		15,376		18		—			(7	)		15,387
Corporate bonds		44,251		19		(10	)		—			44,260
Commercial paper		3,939		—		—			—			3,939
Total cash equivalents and marketable securities	$	190,869	$	178	$	(11	)	$	(7	)	$	191,029

All of the Company’s marketable securities as of June 30, 2026 and December 31, 2025, have a contractual maturity of two years or less.

The Company reviews investments whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. In connection with these investments, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors, considering the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security is compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded for the credit loss on the condensed consolidated balance sheet, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that is not related to credit is recognized in other comprehensive (loss) income. Changes in the allowance for credit losses are recorded as a provision for (or reversal of) credit loss expense in other income, net within the condensed consolidated statement of operations and comprehensive (loss) income. Losses are charged against the allowance when the Company believes the uncollectability of an available-for-sale security is confirmed or when either of the criteria regarding intent or requirement to sell is met. No credit losses were recorded during the periods presented.

As of June 30, 2026 and December 31, 2025, the Company held 58 and 20 marketable securities, respectively, that were in an unrealized loss position, representing $74.5 million and $26.6 million in fair value, respectively. The unrealized losses as of June 30, 2026 and December 31, 2025, were attributable to changes in interest rates and do not represent credit losses. The Company does not intend to sell these securities, and it is not more likely than not that it will be required to sell them before recovery of their amortized cost basis.


	As of June 30,		As of December 31,
	2026		2025
	(in thousands)
Cash and cash equivalents	$	35,769	$	65,300
Restricted cash included in deposits and other non-current assets		2,736		2,736
Total cash, cash equivalents, and restricted cash	$	38,505	$	68,036

Restricted cash balances for both periods presented are held in the form of money market accounts and represent collateral for the Company’s facility lease obligations.

Insider Trading Arrangements

3 Months Ended

Jun. 30, 2026

Trading Arrangements, by Individual

Material Terms of Trading Arrangement

Director and Officer Trading Arrangements

A portion of the compensation of our directors and officers (as defined in Rule 16a-1(f) under the Securities Exchange Act of 1934, as amended, or the Exchange Act) is in the form of equity awards and, from time to time, directors and officers engage in open-market transactions with respect to the securities acquired pursuant to such equity awards or our other securities, including to satisfy tax withholding obligations when equity awards vest or are exercised, and for diversification or other personal reasons.

Transactions in our securities by directors and officers are required to be made in accordance with our insider trading policy, which requires that the transactions be in accordance with applicable U.S. federal securities laws that prohibit trading while in possession of material nonpublic information. Rule 10b5-1 under the Exchange Act provides an affirmative defense that enables directors and officers to prearrange transactions in our securities in a manner that avoids concerns about initiating transactions while in possession of material nonpublic information.

The following table describes, for the quarterly period covered by this report, each trading arrangement for the sale or purchase of our 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
Nancy Vitale (Director)	Adoption (June 7, 2026)	Rule 10b5-1 trading arrangement for exercises of options and sales of shares	Sale	Until September 30, 2027, or such earlier date upon which all transactions are completed or expire without execution	Up to 137,000 shares

Nancy Vitale

Trading Arrangements, by Individual

Name

Nancy Vitale

Title

Director

Rule 10b5-1 Arrangement Adopted

true

June 7, 2026

September 30, 2027

481 days

137,000

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Cash flow from operating activities
Net loss	$ (52,410)	$ (64,403)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	4,921	7,806
Depreciation	1,840	2,079
Amortization of premiums and discounts on marketable securities	(613)	(1,789)
Loss on disposal of fixed assets	105	79
Non-cash lease expense	2,573	2,376
Changes in operating assets and liabilities:
Accounts receivable	(1,171)	(170)
Related party collaboration receivable	(71)	(175)
Prepaid expenses and other current assets	(1,397)	(1,826)
Other non-current assets	(214)
Accounts payable	(3,399)	(2,192)
Accrued expenses	(4,147)	(2,146)
Operating lease liabilities	(3,932)	(3,522)
Deferred revenue	(1,346)	(7,273)
Net cash used in operating activities	(59,261)	(71,156)
Cash flow from investing activities
Purchases of property and equipment	(14)	(1,763)
Purchases of marketable securities	(70,851)	(114,790)
Proceeds from sales and maturities of marketable securities	94,357	159,687
Net cash provided by investing activities	23,492	43,134
Cash flow from financing activities
Proceeds from the exercise of stock options	351	161
Proceeds from the purchase of common stock under ESPP	219	434
Proceeds from the issuance of common stock from at-the-market sales agreement, net of issuance costs	5,668
Net cash provided by financing activities	6,238	595
Net decrease in cash, cash equivalents, and restricted cash	(29,531)	(27,427)
Cash, cash equivalents, and restricted cash, beginning of period	68,036	74,241
Cash, cash equivalents, and restricted cash, end of period	$ 38,505	$ 46,814

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2026	Dec. 31, 2025
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock shares authorized	240,000,000	120,000,000
Common stock shares issued	61,273,390	59,047,860
Common stock share outstanding	61,273,390	59,047,860

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

Number of shares issued for nonredeemable preferred shares and preferred shares redeemable solely at option of issuer. Includes, but is not limited to, preferred shares issued, repurchased, and held as treasury shares. Excludes preferred shares classified as debt.

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Schedule of Reconciliation of Collaboration Revenue and Segment Expenses to Net Loss for Segment

Segment Information (Tables)

6 Months Ended

Jun. 30, 2026

Segment Reporting [Abstract]

The following table reconciles reported collaboration revenue and segment expenses to net loss under the significant expense principle for the three and six months ended June 30, 2026 and 2025:


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2026			2025			2026			2025
Collaboration revenue	$	3,165		$	5,200		$	5,758		$	11,673
External research and development (1):
Anti-tau antibody program (VY7523)		1,959			3,705			4,336			7,954
Tau silencing gene therapy program (VY1706)		2,873			3,414			8,509			6,588
SOD1 silencing gene therapy program		—			380			—			2,266
Partnered programs (2)		1,787			1,898			2,459			2,889
Other programs and platforms (3)		2,437			3,818			4,136			6,999
Internal research and development (4)		7,781			10,263			15,874			20,221
Facilities and other research and development (5)		5,204			7,852			11,329			15,939
General and administrative (5)		7,516			10,495			15,777			20,135
Interest income		1,528			2,831			3,440			6,122
Other income		411			427			846			845
Income tax provision		20			15			34			52
Net loss	$	(24,473	)	$	(33,382	)	$	(52,410	)	$	(64,403	)

(1)

External research and development is allocated to the Company’s programs and platforms and includes laboratory supplies and non-employee consultant and contractor costs.

(2)

(3)

(4)

Internal research and development consist of employee-related expenses, including salaries, benefits, and stock-based compensation expense.

(5)

Depreciation and amortization expense is allocated between general and administrative and facilities and other research and development.

Tabular disclosure of segment reporting. Includes, but is not limited to, reconciliation of reportable segment amount to corresponding consolidated total.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Share-Based Payment Arrangement [Abstract]

Stock-based Compensation (Tables)

6 Months Ended

Jun. 30, 2026

Summary of Compensation Cost Recognized for All Stock-based Compensation Awards

Total compensation cost recognized for all stock‑based compensation awards in the condensed consolidated statements of operations and comprehensive loss was as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
	(in thousands)
Research and development	$	1,128	$	1,629	$	1,788	$	3,114
General and administrative		1,305		2,504		3,133		4,692
Total stock-based compensation expense	$	2,433	$	4,133	$	4,921	$	7,806

Summary of Status and Changes in Unvested Restricted Stock and Performance-based Restricted Stock Units


				Weighted Average Grant
	Units			Date Fair Value Per Unit
Unvested as of December 31, 2025		2,296,920		$	5.39
Granted		797,398			3.71
Vested		(600,929	)		6.18
Forfeited		(578,021	)		5.39
Outstanding as of June 30, 2026		1,915,368		$	4.44

Summary of Stock Option Activity

The following is a summary of stock option activity for the six months ended June 30, 2026:


				Weighted		Remaining		Aggregate
				Average		Contractual		Intrinsic Value
	Shares			Exercise Price		Life (in years)		(in thousands)
Outstanding as of December 31, 2025		9,613,881		$	7.26		6.8	$	1,251
Granted		2,650,700			3.69
Exercised		(192,931	)		3.13
Cancelled or forfeited		(1,981,796	)		7.25
Outstanding as of June 30, 2026		10,089,854		$	6.41		7.1	$	596
Exercisable as of June 30, 2026		6,268,111		$	7.52		6.0	$	534

Related-Party Transactions

6 Months Ended

Jun. 30, 2026

Related-Party Transactions

11. Related‑party transactions

During the three and six months ended June 30, 2026, the Company received scientific advisory and consulting services from one of its prior executives, Dinah Sah, Ph.D., the Company’s former Chief Scientific Officer. The total amount of fees paid to Dr. Sah for services provided during the three months ended June 30, 2026 and 2025 was $0.2 million and $0.1 million, respectively. The total amount of fees paid to Dr. Sah for services provided during each of the six months ended June 30, 2026 and 2025 was $0.3 million.

Under both the 2019 Neurocrine Collaboration Agreement and the 2023 Neurocrine Collaboration Agreement, the Company and Neurocrine have agreed to conduct research, development and commercialization activities for certain of the Company’s AAV gene therapy product candidates. Any amounts due from Neurocrine are reflected as related party collaboration receivable. Amounts received from Neurocrine that have not yet been recognized as revenue are reflected as deferred revenue. Refer to Note 8 for further description of these account balances.

For the three months ended June 30, 2026 and 2025, the Company recognized collaboration revenue of $0.4 million and $3.7 million, respectively, related to the 2023 and 2019 Neurocrine Collaboration Agreements. For the six months ended June 30, 2026 and 2025, the Company recognized collaboration revenue of $1.8 million and $8.6 million, respectively, related to the 2023 and 2019 Neurocrine Collaboration Agreements.

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Schedule of outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share

Net Loss Per Share (Tables)

6 Months Ended

Jun. 30, 2026

Earnings Per Share [Abstract]

The following table sets forth the outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because to include them would be anti-dilutive:


	As of June 30,
	2026		2025
Unvested RSUs and PRSUs		1,915,368		2,726,298
Outstanding stock options		10,089,854		10,345,167
Total		12,005,222		13,071,465

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Stockholders' Equity, Beginning Balance at Dec. 31, 2024	$ 299,760	$ 55	$ 626,296	$ (407)	$ (326,184)
Shares, Outstanding, Beginning Balance at Dec. 31, 2024		54,731,316
Exercises of stock options	82		82
Exercises of stock options (in shares)		27,613
Vesting of restricted stock units (in shares)		450,556
Stock-based compensation expense	3,673		3,673
Unrealized gain (loss) on available-for-sale securities, net of tax	208			208
Net loss	(31,021)				(31,021)
Stockholders' Equity, Ending Balance at Mar. 31, 2025	272,702	$ 55	630,051	(199)	(357,205)
Shares, Outstanding, Ending Balance at Mar. 31, 2025		55,209,485
Stockholders' Equity, Beginning Balance at Dec. 31, 2024	299,760	$ 55	626,296	(407)	(326,184)
Shares, Outstanding, Beginning Balance at Dec. 31, 2024		54,731,316
Unrealized gain (loss) on available-for-sale securities, net of tax	186
Net loss	(64,403)
Stockholders' Equity, Ending Balance at Jun. 30, 2025	243,944	$ 56	634,696	(221)	(390,587)
Shares, Outstanding, Ending Balance at Jun. 30, 2025		55,434,956
Stockholders' Equity, Beginning Balance at Mar. 31, 2025	272,702	$ 55	630,051	(199)	(357,205)
Shares, Outstanding, Beginning Balance at Mar. 31, 2025		55,209,485
Exercises of stock options	79	$ 1	78
Exercises of stock options (in shares)		27,433
Vesting of restricted stock units (in shares)		99,528
Issuance of common stock under ESPP	434		434
Issuance of common stock under ESPP (in shares)		98,510
Stock-based compensation expense	4,133		4,133
Unrealized gain (loss) on available-for-sale securities, net of tax	(22)			(22)
Net loss	(33,382)				(33,382)
Stockholders' Equity, Ending Balance at Jun. 30, 2025	243,944	$ 56	634,696	(221)	(390,587)
Shares, Outstanding, Ending Balance at Jun. 30, 2025		55,434,956
Stockholders' Equity, Beginning Balance at Dec. 31, 2025	196,081	$ 59	641,895	32	(445,905)
Shares, Outstanding, Beginning Balance at Dec. 31, 2025		59,047,860
Exercises of stock options	294		294
Exercises of stock options (in shares)		87,081
Vesting of restricted stock units (in shares)		545,015
Issuance of common stock from at-the-market sales agreement, net of issuance costs	3,038	$ 1	3,037
Issuance of common stock from at-the-market sales agreement, net of issuance costs (in shares)		630,570
Stock-based compensation expense	2,488		2,488
Unrealized gain (loss) on available-for-sale securities, net of tax	(295)			(295)
Net loss	(27,937)				(27,937)
Stockholders' Equity, Ending Balance at Mar. 31, 2026	173,669	$ 60	647,714	(263)	(473,842)
Shares, Outstanding, Ending Balance at Mar. 31, 2026		60,310,526
Stockholders' Equity, Beginning Balance at Dec. 31, 2025	$ 196,081	$ 59	641,895	32	(445,905)
Shares, Outstanding, Beginning Balance at Dec. 31, 2025		59,047,860
Exercises of stock options (in shares)	192,931
Unrealized gain (loss) on available-for-sale securities, net of tax	$ (453)
Net loss	(52,410)
Stockholders' Equity, Ending Balance at Jun. 30, 2026	154,377	$ 61	653,052	(421)	(498,315)
Shares, Outstanding, Ending Balance at Jun. 30, 2026		61,273,390
Stockholders' Equity, Beginning Balance at Mar. 31, 2026	173,669	$ 60	647,714	(263)	(473,842)
Shares, Outstanding, Beginning Balance at Mar. 31, 2026		60,310,526
Exercises of stock options	57		57
Exercises of stock options (in shares)		105,481
Vesting of restricted stock units (in shares)		55,914
Issuance of common stock under ESPP	219		219
Issuance of common stock under ESPP (in shares)		73,473
Issuance of common stock from at-the-market sales agreement, net of issuance costs	2,630	$ 1	2,629
Issuance of common stock from at-the-market sales agreement, net of issuance costs (in shares)		727,996
Stock-based compensation expense	2,433		2,433
Unrealized gain (loss) on available-for-sale securities, net of tax	(158)			(158)
Net loss	(24,473)				(24,473)
Stockholders' Equity, Ending Balance at Jun. 30, 2026	$ 154,377	$ 61	$ 653,052	$ (421)	$ (498,315)
Shares, Outstanding, Ending Balance at Jun. 30, 2026		61,273,390

Cash Equivalents and Available-for-Sale Marketable Securities - Schedule of Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 35,769	$ 65,300
Restricted cash included in deposits and other non-current assets	2,736	2,736
Total cash, cash equivalents, and restricted cash	$ 38,505	$ 68,036	$ 46,814	$ 74,241