0001628280-26-017253 | 10-K | XBRL Viewer

Fair Value Measurements

12 Months Ended

Dec. 31, 2025

The following table sets forth the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis based on the three-tier fair value hierarchy (in thousands):


	December 31, 2025
	Level 1		Level 2		Level 3		Total
Financial assets:
Money market funds	$	49,766	$	—	$	—	$	49,766
U.S. Treasury securities	—		176,072		—		176,072
U.S. government agency securities	—		6,533		—		6,533
Corporate debt securities	—		4,434		—		4,434
Total financial assets	$	49,766	$	187,039	$	—	$	236,805
Financial liabilities:
SPA put/call	$	—	$	—	$	11,411	$	11,411
Success payment liabilities	—		—		1,242		1,242
Total financial liabilities	$	—	$	—	$	12,653	$	12,653


	December 31, 2024
	Level 1		Level 2		Level 3		Total
Financial assets:
Money market funds	$	73,975	$	—	$	—	$	73,975
U.S. Treasury securities	—		226,271		—		226,271
U.S. government agency securities	—		36,815		—		36,815
Corporate debt securities	—		21,492		—		21,492
Marketable equity security	30		—		—		30
Total financial assets	$	74,005	$	284,578	$	—	$	358,583
Financial liabilities:
Contingent consideration payable	$	—	$	—	$	7,600	$	7,600
Success payment liabilities	—		—		411		411
Total financial liabilities	$	—	$	—	$	8,011	$	8,011

The Company measures the fair value of money market funds based on quoted prices in active markets for identical assets or liabilities. The Company measures the fair value of marketable equity securities traded in active markets based on quoted prices of identical assets. The Level 2 marketable securities include U.S. Treasury securities, U.S. government agency securities and corporate debt securities, which are valued using third-party pricing sources. The pricing services applied industry standard valuation models. Inputs utilized include market pricing based on real-time trade data for the same or similar securities and other significant inputs derived from or corroborated by observable market data.

In July 2025, the Company completed a $50.0 million equity financing that included issuance of mutually exclusive put and call rights related to potential future equity issuance of up to an additional $50.0 million financing. See Note 21, Subsequent Events, for more information about the Company’s exercise of the SPA put right. These rights were accounted for as a combined financial asset or liability and measured at fair value on a recurring basis. The SPA put/call is presented within accrued liabilities and other current liabilities on the Company’s consolidated balance sheet as of December 31, 2025. See Note 13, Stockholders’ Equity, for additional information regarding the SPA put/call liability. The SPA put/call is classified as a Level 3 financial instrument and the fair value at inception on July 24, 2025 and period-end on December 31, 2025 were estimated using the Monte Carlo simulation valuation method including the following assumptions:


	July 24, 2025		December 31, 2025
Time to maturity (years)	1.11		0.67
Risk-free rate	4.08	%	3.55	%
Volatility	91	%	90	%

The Company’s contingent consideration payable, success payment liabilities and SPA put/call are classified as Level 3 financial instruments. In July 2025, the Company issued 625,000 shares of common stock valued at $5.9 million upon achievement of a specific clinical milestone, thereby settling the contingent consideration payable related to the ImmPACT acquisition. Prior to settlement, the liability was valued using the Company’s common stock price and management’s assessment of the probability of achieving either (i) specified clinical milestones or (ii) certain regulatory approvals. The success payment liabilities were estimated by management using its historical experience of the correlation of success payment fair values relative to the Company’s stock price. See Note 3, Acquisitions, for additional information regarding the contingent consideration payable.

The Company utilizes estimates and assumptions in determining the estimated contingent consideration payable, success payment liabilities and SPA put/call and associated changes in fair value. A small change in the value of the Company’s common stock may have a relatively large change in the estimated fair value of the contingent consideration payable, success payment liabilities and SPA put/call and associated changes in fair value. Additionally, a small change in management’s assessment of the likelihood of achieving either (i) the specified clinical milestones or (ii) certain regulatory approvals related to the estimated valuation of the contingent consideration payable may have a relatively large change in the estimated fair value. A small change in management’s assessment of the likelihood of achieving either a clinical

milestone relating to the Company’s ongoing PiNACLE pivotal trial or certain other corporate milestones relevant to the SPA put/call may have a material change in its estimated fair value.

The following table sets forth a summary of the changes in the fair value of the Company’s Level 3 financial liabilities (in thousands):


	Contingent Consideration Payable		Success Payment Liabilities		SPA put/call (Asset) Liability
Balance at December 31, 2023	$	—	$	1,576	$	—
Issuance	11,404		—		—
Change in fair value (1)	(3,804)		(1,165)		—
Balance at December 31, 2024	7,600		411		—
Issuance	—		—		(7,774)
Change in fair value (1)	(1,706)		831		19,185
Settlement via equity issuance	(5,894)		—		—
Balance at December 31, 2025	$	—	$	1,242	$	11,411

__________

(1)The change in fair value of the contingent consideration payable subsequent to Closing Date, Fred Hutch success payment liabilities and SPA put/call (asset) liability are recorded in other (expense) income, net. Changes in the fair value of Stanford success payment liabilities are recorded as either other (expense) income, net or research and development expenses, depending on the period. (See Note 4, License, Collaboration, and Success Payment Agreements.)

In October 2022, the Company received non-voting PACT Series D convertible preferred stock with an estimated fair value of $2.9 million using the cost approach. Under this approach, the fair value of an asset is measured by the cost to reconstruct or replace such asset with another one of like utility. The fair value of PACT was estimated by using significant unobservable inputs, including an estimate of insignificant fair value associated with PACT intangible assets. Accordingly, the Company classified the fair value measurement of PACT preferred stock on October 1, 2022 as Level 3 under the fair value hierarchy. In June 2023, the Company performed a qualitative assessment of potential indicators of impairment of the PACT Series D convertible preferred stock investment, resulting in a $2.9 million impairment expense for the year ended December 31, 2023.

- 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.

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+ Details

Fair Value Measurements - Schedule of Changes in Estimated Fair Value of Financial Liabilities (Details) - Level 3 - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Contingent Consideration Payable
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 7,600	$ 0
Issuance	0	11,404
Change in fair value	(1,706)	(3,804)
Settlement via equity issuance	(5,894)
Ending Balance	0	7,600
Success Payment Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	411	1,576
Issuance	0	0
Change in fair value	831	(1,165)
Settlement via equity issuance	0
Ending Balance	1,242	411
Securities Purchase Agreement
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	0	0
Issuance	7,774	0
Change in fair value	19,185	0
Settlement via equity issuance	0
Ending Balance	$ 11,411	$ 0

Property and Equipment, Net - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 10,400	$ 19,400	$ 20,200
Impairment of long-lived assets	1,443	51,297	0
Leasehold improvements
Property, Plant and Equipment [Line Items]
Impairment of long-lived assets	$ 0	$ 38,700	$ 0

Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2025

Share-Based Payment Arrangement [Abstract]

Schedule of Stock-based Compensation Expense by Classification

Stock-based compensation expense by classification included within the consolidated statements of operations and comprehensive loss was as follows (in thousands):


	Year Ended December 31,
	2025		2024		2023
Research and development	$	28,743	$	14,577	$	18,207
General and administrative	13,086		18,567		28,877
Total stock-based compensation expense	$	41,829	$	33,144	$	47,084

Schedule of PSU Activity

A summary of the Company’s PSU activity was as follows:


	Performance-Based Restricted Stock Units Outstanding	Weighted-Average Value at Grant Date Per Share
Unvested PSUs as of December 31, 2024	135,170	$	37.63
PSUs granted(1)	—	$	—
PSUs vested	(33,623)	$	36.00
PSUs forfeited or canceled	(36,029)	$	39.36
Unvested PSUs as of December 31, 2025	65,518	$	37.51

(1) PSU grants reflect the target number of shares eligible to be earned at the time of grant.

Schedule of RSU Activity

A summary of the Company’s RSU activity was as follows:


	Restricted Stock Units Outstanding	Weighted-Average Value at Grant Date Per Share
Unvested RSUs as of December 31, 2024	281,190	$	34.40
RSUs granted	287,735	$	11.82
RSUs vested	(139,928)	$	25.66
RSUs forfeited or canceled	(122,582)	$	24.88
Unvested RSUs as of December 31, 2025	306,415	$	19.77

Schedule of Stock Option Activity

A summary of the Company’s PBO activity was as follows:


	Number of PBOs	Weighted-Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
PBOs outstanding as of December 31, 2024	—	$	—	—	$	—
Granted(1)	138,250	$	11.07
Exercised	—	$	—
Canceled or forfeited	(39,382)	$	11.07
PBOs outstanding as of December 31, 2025	98,868	$	11.07	9.11	$	1,949
PBOs exercisable as of December 31, 2025	—	$	—	—	$	—

(1) PBO grants reflect the target number of shares eligible to be earned at the time of grant.

A summary of the Company’s stock option activity was as follows:


	Number of Stock Options	Weighted-Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Options outstanding as of December 31, 2024	2,239,354	$	49.80	6.62	$	1,479
Granted	864,491	$	14.25
Exercised	(3,750)	$	11.07
Canceled or forfeited	(403,651)	$	36.96
Options outstanding as of December 31, 2025	2,696,444	$	40.32	6.14	$	17,090
Options exercisable as of December 31, 2025	1,660,556	$	52.51	4.40	$	4,704

Schedule of Assumptions Used in Black-Scholes Option-Pricing Model for Estimating Fair Value of Stock Options Granted

The fair value of stock options and performance-based stock options granted to employees, directors and consultants valued using the Black-Scholes option pricing model was estimated on the date of grant using the following weighted-average assumptions:


	Year Ended December 31,
	2025		2024		2023
Risk-free interest rate	4.05	%	4.17	%	4.13	%
Expected volatility	85.7	%	75.9	%	88.0	%
Expected term (in years)	6.04		5.89		6.06
Expected dividend yield	0	%	0	%	0	%

Stockholders’ Equity	12 Months Ended
Stockholders’ Equity	Dec. 31, 2025
Equity [Abstract]
Stockholders’ Equity	Stockholders’ Equity Preferred Stock The Company is authorized to issue 10 million shares of preferred stock with a par value of $0.0001 per share. As of December 31, 2025 and 2024, no shares of preferred stock were outstanding. Common Stock The Company is authorized to issue 500 million shares of common stock with a par value of $0.0001 per share. As of December 31, 2025 and 2024, there were 21,251,353 shares and 14,743,777 shares of the Company’s common stock outstanding, respectively. On February 28, 2024, the Company entered into a sales agreement with Cowen and Company, LLC (“Cowen”) acting as the Company’s sales agent (the “Sales Agreement”), pursuant to which the Company may offer and sell shares of common stock having an aggregate offering price of up to $150.0 million from time to time in a series of one or more at‑the‑market equity offerings. The Company will pay Cowen commissions of up to 3% of the gross proceeds of the sale, and reimbursement of certain expenses, under this agreement. Neither the Company nor Cowen is obligated to sell any shares. As of December 31, 2025, the Company had not made any sales under the Sales Agreement. In July 2025, the Company entered into the SPA with certain institutional and other accredited investors (the “Purchasers”), pursuant to which the Company sold and issued 3,753,752 shares of common stock at a purchase price of $13.32 per share at an initial closing, for gross proceeds of approximately $50.0 million. Pursuant to the SPA, the Company had the right, but not the obligation, to require the Purchasers to purchase approximately $50.0 million of additional shares of common stock (and/or pre-funded warrants in lieu of common stock) at a closing (the “Milestone Closing”) upon the occurrence of a milestone event within 12 months following the initial closing (the “Put Right”). The purchase price per share of common stock in the Milestone Closing will be $25.61, unless the closing price of the common stock on the date before the Milestone Closing is less than $10.41, in which case it will be $10.41 per share. If the purchase price in the Milestone Closing will be $10.41 per share, the Company may rescind its Milestone Closing election before completion of the Milestone Closing. At any time before the Milestone Closing and until the later of 12 months following the initial closing and 40 days after the Purchasers receive notice from the Company of the achievement of a milestone event, each Purchaser will have the right, but not the obligation, to purchase at a closing (each, an “Investor Call Closing”) the same dollar amount of common stock (or pre-funded warrants in lieu thereof) it has committed to purchase in the Milestone Closing, at a purchase price of $30.73 per share. If any Purchaser exercises its right to hold its Investor Call Closing, it will not participate in any subsequent Milestone Closing. In addition, subject to specified exceptions, if the Company completes a bona fide equity financing for capital-raising purposes on terms that are more favorable to investors than the terms of the Investor Call Closing, the Company’s right to hold the Milestone Closing will terminate. The Milestone Closing and Investor Call Closing (the “SPA put/call”) were determined to be a combined financial instrument as they are mutually exclusive. The Company evaluated the SPA put/call under ASC 815 and concluded it does not meet the definition of a derivative. See Note 8, Fair Value Measurements, for additional information regarding the valuation of the SPA put/call liability. See Note 21, Subsequent Events, for more information about the Company’s exercise of the SPA put right.

- Definition

The entire disclosure for equity.

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+ Details

Stock-based Compensation - Schedule of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Number of Stock Options
Beginning Balance (in shares)	2,239,354
Granted (in shares)	864,491
Exercised (in shares)	(3,750)
Canceled or forfeited (in shares)	(403,651)
Ending Balance (in shares)	2,696,444	2,239,354
Options Exercisable (in shares)	1,660,556
Weighted-Average Exercise Price per Share
Beginning Balance (in dollars per share)	$ 49.80
Granted (in dollars per share)	14.25
Exercised (in dollars per share)	11.07
Cancelled or forfeited (in dollars per share)	36.96
Ending Balance (in dollars per share)	40.32	$ 49.80
Options Exercisable (in dollars per share)	$ 52.51
Weighted-Average Remaining Contractual Life (in years)
Options Outstanding	6 years 1 month 20 days	6 years 7 months 13 days
Options Exercisable	4 years 4 months 24 days
Aggregate Intrinsic Value
Options Outstanding	$ 17,090	$ 1,479
Options Exercisable	$ 4,704
Performance-Based Stock Options
Number of Stock Options
Beginning Balance (in shares)	0
Granted (in shares)	138,250
Exercised (in shares)	0
Canceled or forfeited (in shares)	(39,382)
Ending Balance (in shares)	98,868	0
Options Exercisable (in shares)	0
Weighted-Average Exercise Price per Share
Beginning Balance (in dollars per share)	$ 0
Granted (in dollars per share)	11.07
Exercised (in dollars per share)	0
Cancelled or forfeited (in dollars per share)	11.07
Ending Balance (in dollars per share)	11.07	$ 0
Options Exercisable (in dollars per share)	$ 0
Weighted-Average Remaining Contractual Life (in years)
Options Outstanding	9 years 1 month 9 days
Aggregate Intrinsic Value
Options Outstanding	$ 1,949	$ 0
Options Exercisable	$ 0

Leases

12 Months Ended

Dec. 31, 2025

Leases [Abstract]

Leases

The Company’s lease portfolio is comprised of operating leases for laboratory, office and manufacturing facilities located in South San Francisco and Los Angeles, California, and Seattle and Bothell, Washington with contractual periods expiring between January 2028 and March 2031. In addition to minimum rent, the leases require payment of real estate taxes, insurance, common area maintenance charges and other executory costs. These additional charges are considered variable lease costs and are recognized in the period in which the costs are incurred.

In 2018, the Company entered into an operating lease for approximately 34,000 square feet of office and laboratory space in Seattle, Washington, with an initial lease term expiring in December 2028. The Company has two five‑year options to extend the lease, which are not reasonably assured.

In 2019, the Company entered into two operating lease agreements for a combined approximately 73,000 square feet of space to develop a cell therapy manufacturing facility located in Bothell, Washington, with initial terms expiring in May 2030. The Company has two 90-month options to extend the leases, which are not reasonably assured.

In 2019, the Company entered into an operating lease agreement for approximately 108,000 square feet of office and laboratory space located in South San Francisco, California. The initial lease term expires in January 2031 with the option to extend the term for another 10 years, which is not reasonably assured. In January 2021, the Company amended the lease term to extend the lease expiration to March 2031.

On the ImmPACT acquisition Closing Date, the Company acquired an operating lease agreement for approximately 26,000 square feet of office and laboratory space located in Los Angeles, California, with an initial lease term expiring in January 2028. See Note 3, Acquisitions, for further information regarding the ImmPACT acquisition. The Company has one five-year option to extend the lease, which is not reasonably assured.

The following table summarizes the Company’s future minimum operating lease commitments, including lease incentives, as of December 31, 2025 (in thousands):


Year Ending December 31:
2026	$	12,959
2027	13,341
2028	13,005
2029	10,398
2030	9,855
Thereafter	2,333
Total undiscounted lease payments	61,891
Less: imputed interest	(10,897)
Total operating lease liabilities	$	50,994

Reported as of December 31, 2025:
Short-term portion of lease liabilities (included in accrued liabilities and other current liabilities)	$	9,073
Operating lease liabilities, non-current	41,921
Total	$	50,994

The operating lease costs for all operating leases were $9.1 million, $9.2 million and $9.0 million for the years ended December 31, 2025, 2024 and 2023, respectively. The operating lease costs and total commitments for short-term leases were de minimis for the years ended December 31, 2025, 2024 and 2023. Variable lease costs for operating leases were $6.9 million, $7.1 million and $5.4 million for the years ended December 31, 2025, 2024 and 2023, respectively. The weighted-average remaining lease terms for operating leases were 4.8 years and 5.7 years as of December 31, 2025 and 2024, respectively. The weighted-average discount rates for operating leases were 8.5% as of both December 31, 2025 and 2024.

The Company entered into subleases in May 2021 and September 2024, whereby the Company agreed to sublease approximately 11,000 and 12,150 square feet, respectively, currently leased by the Company in South San Francisco, California. These subleases are classified as operating leases and will expire in March 2031 and July 2026, respectively.

In September 2021, the Company entered into a sublease with Sonoma Biotherapeutics, Inc. (“Sonoma”), a related party, whereby the Company agreed to sublease approximately 18,000 square feet of space in South San Francisco, California currently leased by the Company. See Note 19, Related-Party Transactions. As a part of the sublease, in September 2021, the Company received a $4.6 million tenant improvement contribution payment, which will be recognized over the term of the sublease. The sublease is classified as an operating lease and will expire in September 2026. The Company recognized Sonoma sublease income of $1.9 million for each of the years ended December 31, 2025, 2024 and 2023.

The Company’s sublease income is recognized within other operating income, net in the consolidated statements of operations and comprehensive Loss. Total operating income from the subleases and income solely attributable to the subleases are shown in the table below (in thousands). Total operating income includes income attributable to the subleases, as well as additional operating fees recognized in other operating income, net such as common area maintenance charges.


	Year Ended December 31,
	2025		2024		2023
Other operating income, net - subleases	$	5,466	$	4,530	$	4,152
Sublease income	$	3,601	$	3,004	$	2,729

During the year ended December 31, 2025 and 2024, the Company recorded impairment losses of $1.4 million and $12.6 million for lease right‑of‑use assets, respectively. The Company did not record any impairment losses for lease right-of-use assets in 2023. See Note 5, Impairment of Long‑Lived Assets, for further information.

Leases

The following table summarizes the Company’s future minimum operating lease commitments, including lease incentives, as of December 31, 2025 (in thousands):


Year Ending December 31:
2026	$	12,959
2027	13,341
2028	13,005
2029	10,398
2030	9,855
Thereafter	2,333
Total undiscounted lease payments	61,891
Less: imputed interest	(10,897)
Total operating lease liabilities	$	50,994

Reported as of December 31, 2025:
Short-term portion of lease liabilities (included in accrued liabilities and other current liabilities)	$	9,073
Operating lease liabilities, non-current	41,921
Total	$	50,994


	Year Ended December 31,
	2025		2024		2023
Other operating income, net - subleases	$	5,466	$	4,530	$	4,152
Sublease income	$	3,601	$	3,004	$	2,729

Acquisitions - Schedule of Estimated Fair Value of Assets Acquired (Details) - USD ($) $ in Thousands	Nov. 06, 2025	Oct. 31, 2024
ICT License Acquisition
Asset Acquisition [Line Items]
Prepaid clinical supply	$ 8,835
LYL273 license	66,332
Total assets	$ 75,167
ImmPACT Bio USA Inc.
Asset Acquisition [Line Items]
Cash and cash equivalents		$ 14,982
Prepaid expenses and other current assets		1,211
Property and equipment, net		4,446
Long-term deposits		459
Operating lease right-of-use assets		1,816
Assembled workforce intangible asset		1,315
IPR&D asset		87,184
Total assets		111,413
Accounts payable and other current liabilities		16,090
Operating lease liability, long-term		1,580
Total liabilities assumed		17,670
Total net assets acquired		$ 93,743

Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2025

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment, Net

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


	December 31,
	2025		2024
Leasehold improvements	$	79,739	$	79,613
Laboratory equipment	26,372		36,106
Computer equipment and software	1,672		1,805
Furniture and fixtures	814		1,114
Construction in progress	452		241
Property and equipment, at cost	109,049		118,879
Less: Accumulated depreciation and amortization	(74,278)		(70,679)
Total property and equipment, net	$	34,771	$	48,200

Leases - Schedule of Total Income Attributable to Sublease (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Other operating income, net - subleases	$ 5,466	$ 4,530	$ 4,152
Sublease income	$ 3,601	$ 3,004	$ 2,729

Cash Equivalents and Marketable Securities - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Marketable Securities [Line Items]
Fair value of securities held in a continuous unrealized loss position for less than twelve months	$ 0.0	$ 31.7
Fair value of securities held in a continuous unrealized loss position for greater than twelve months	$ 0.0	$ 0.0
Maximum
Marketable Securities [Line Items]
Maturity of marketable securities (in years)	2 years	2 years

Segment - Schedule of Reporting Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Revenue	$ 36	$ 61	$ 130
Net loss	274,448	342,994	234,632
Reportable segment
Segment Reporting Information [Line Items]
Revenue	36	61	130
Technical operations	47,202	46,102	49,851
Clinical development	36,671	38,561	27,241
Support functions	25,737	29,870	34,096
Lease costs	16,643	16,885	14,788
Operations management	13,106	14,145	22,814
Research activities	11,038	25,284	33,309
Other segment items	124,087	172,208	52,663
Net loss	$ 274,448	$ 342,994	$ 234,632

Consolidated Statements of Operations and Comprehensive Loss - USD ($)
shares in Thousands, $ in Thousands

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Statement of Comprehensive Income [Abstract]

Revenue

$ 36

$ 61

$ 130

Operating expenses:

Research and development

158,675

171,603

182,945

General and administrative

45,135

52,041

66,983

Other operating income, net

(2,145)

(3,309)

(2,790)

Acquired in-process research and development

66,332

87,184

Impairment of long-lived assets

1,443

51,297

Total operating expenses

269,440

358,816

247,138

Loss from operations

(269,404)

(358,755)

(247,008)

Interest income, net

13,080

24,068

23,453

Other (expense) income, net

(18,124)

4,694

1,846

Impairment of other investments

(13,001)

(12,923)

Total other (loss) income, net

(5,044)

15,761

12,376

Net loss

(274,448)

(342,994)

(234,632)

Other comprehensive loss:

Net unrealized (loss) gain on marketable securities

(49)

385

7,505

Comprehensive loss

$ (274,497)

$ (342,609)

$ (227,127)

Net loss per common share, basic (in dollars per share)

^[1]

$ (16.06)

$ (26.23)

$ (18.70)

Net loss per common share, diluted (in dollars per share)

^[1]

$ (16.06)

$ (26.23)

$ (18.70)

Weighted-average shares used to compute net loss per common share, basic (in shares)

^[1]

17,093

13,074

12,549

Weighted-average shares used to compute net loss per common share, diluted (in shares)

^[1]

17,093

13,074

12,549

[1]	1. Amounts previously reported have been retroactively adjusted to reflect the 1-for-20 reverse stock split effected on May 30, 2025. See Note 2.

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 109,049	$ 118,879
Less: Accumulated depreciation and amortization	(74,278)	(70,679)
Total property and equipment, net	34,771	48,200
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	79,739	79,613
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	26,372	36,106
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	1,672	1,805
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	814	1,114
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 452	$ 241

Basis of Presentation and Significant Accounting Policies	12 Months Ended
	Dec. 31, 2025
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies Basis of Presentation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All significant intercompany transactions and balances have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform with the current period presentation. Reverse Stock Split On May 30, 2025, the Company effected a 1-for-20 reverse stock split (“Reverse Split”) of its issued and outstanding shares of common stock, and the common stock began trading on a split-adjusted basis on June 2, 2025. The Reverse Split did not reduce the total number of authorized shares of common stock or the Company’s preferred stock or change the par values per share of the common stock or preferred stock. The Reverse Split affected all stockholders uniformly and did not affect any stockholder’s ownership percentage of the shares of common stock (except to the extent that the Reverse Split resulted in some of the stockholders receiving cash in lieu of fractional shares). All outstanding equity awards entitling their holders to shares of common stock were adjusted as a result of the Reverse Split, in accordance with the terms of each such security. In addition, the number of shares reserved for future issuance pursuant to the Company’s equity incentive plans was adjusted accordingly. As a result, all historical per share data, the number of shares issued and outstanding and outstanding equity awards for the periods presented in the accompanying consolidated financial statements and notes thereto have been adjusted retroactively in this Form 10-K, where applicable, to reflect the Reverse Split. As the par value per share of the common stock was unchanged, corresponding amounts have been reclassified from common stock to additional paid-in capital. Liquidity and Management’s Plan The Company discovers and develops product candidates that involve experimental technologies. The product candidates may require several years and substantial expenditures to complete and ultimately may be unsuccessful. The Company expects to continue to incur significant operating losses for the foreseeable future and may never be profitable. As a result, the Company will need to raise additional capital through equity offerings, debt financings or other capital sources, including potential collaborations, licenses and other similar arrangements. Management believes that it has sufficient working capital on hand to fund operations through at least the next 12 months from the date these consolidated financial statements are issued. Summary of Significant Accounting Policies Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with GAAP requires management to make judgments, estimates and assumptions that affect reported amounts and related disclosures. Specific accounts that require management estimates include, but are not limited to, stock-based compensation, valuation of long‑lived and acquired assets, the SPA put/call (as defined below) liability, other investments and accrued expenses. See Note 13, Stockholders’ Equity, for additional information regarding the SPA put/call. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results could differ materially from those estimates. Comprehensive Loss Comprehensive loss includes net loss and certain changes in stockholders’ equity that are excluded from net loss. For the years ended December 31, 2025, 2024 and 2023, this was comprised of net unrealized gains and losses on the Company’s marketable securities. Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents consist primarily of amounts invested in investment grade fixed income securities and money market accounts. Restricted cash is cash held in a bank account and is used as collateral associated with the Company’s corporate credit card program as well as collateral for a letter of credit in favor of one of the Company’s landlords. Marketable Securities The Company generally invests its excess cash in investment grade short- to intermediate-term fixed income securities. Such investments are classified as available-for-sale and are carried at fair value, with the unrealized gains and losses reported as a component of comprehensive loss. Realized gains and losses on available-for-sale securities are included in other (expense) income, net. The cost of investments sold is based on the specific-identification method. The Company classifies those investments that are not required for use in current operations and that mature in more than 12 months as non-current marketable securities in the accompanying consolidated balance sheets. Each reporting period, the Company evaluates whether declines in fair value below carrying value are due to expected credit losses, as well as the Company’s ability and intent to hold the investment until a forecasted recovery occurs. Expected credit losses, if any, are recorded as an allowance through other (expense) income, net. Valuation of Other Investments The Company accounts for its strategic equity interests in common stock and in-substance common stock in non‑publicly traded companies for which it does not have the ability to exercise significant influence in accordance with Accounting Standards Codification (“ASC”) 321, Investments – Equity Securities (“ASC 321”). Upon acquisition, these investments are measured at cost, which represents the then fair value. Under ASC 321, the Company can elect to subsequently measure the investments at initial cost, minus impairment and any changes, plus or minus, resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer (“measurement alternative”). This election must be made for each investment separately. The Company has made this election for all investments in this category and will continue to measure these investments using this method until they no longer qualify to be measured in accordance with this method. Changes in the carrying value of other investments are recognized through net loss. Each reporting period, the Company performs a qualitative assessment to evaluate whether the investment is impaired. The Company’s assessment includes a review of recent operating results and trends, recent sales/acquisitions of the investee securities and other factors that raise concerns about the investee’s ability to continue as a going concern. If the investment is impaired, an impairment charge is recognized in the amount by which the carrying amount of the investment exceeds the estimated fair value of the investment, with the impairment charge recognized through net loss. See Note 7, Other Investments, for details related to investment impairments recognized during the years ended December 31, 2025, 2024 and 2023. Property and Equipment, Net Property and equipment primarily consist of laboratory equipment, computer equipment and software, furniture and fixtures and leasehold improvements. Property and equipment are stated at cost less accumulated depreciation and amortization and, if applicable, impairment charges. Depreciation is calculated using the straight-line method based on the estimated useful lives of the related assets, which are generally three to five years. For leasehold improvements, amortization is calculated using the straight‑line method based on the shorter of the useful life or the lease term. When assets are retired or otherwise disposed of, the cost and related accumulated depreciation and amortization are removed from the balance sheet and the resulting gain or loss is recorded in other operating income, net in the period realized. Maintenance and repairs are expensed as incurred. The Company reviews its property and equipment for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Valuation of Long-lived Assets Long-lived assets are reviewed each reporting period for impairment or whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable, which may warrant adjustments to carrying values or estimated useful lives. Recoverability is measured by comparison of the carrying amount of an asset group to the future net undiscounted cash flows that the assets are expected to generate. If the carrying amount of an asset group exceeds its estimated future cash flows, an impairment charge is recognized in the amount by which the carrying amount of the asset group exceeds the fair value of the asset group. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the projected discounted future net cash flows arising from the asset group. Any impairment loss is allocated to the long-lived assets of the group on a pro rata basis using the relative carrying amounts of those assets, except that the carrying amount of an individual asset shall not be reduced below its fair value. The Company recognized impairment of long-lived assets expense of $1.4 million for the year ended December 31, 2025, $51.3 million for the year ended December 31, 2024 and zero for the year ended December 31, 2023. See Note 5, Impairment of Long-Lived Assets, for details related to long-lived asset impairments recognized during the years ended December 31, 2025 and 2024. Factors that may indicate potential impairment and trigger an impairment test include, but are not limited to, general macroeconomic conditions, conditions specific to the industry and market, business climate or operational performance of the business and sustained decline in the stock price and market capitalization compared to net book value. Calculating the fair value of a reporting unit, an asset group and an individual asset involves significant estimates and assumptions. These estimates and assumptions include, among others, projected future cash flows, risk-adjusted discount rates, future economic and market conditions, and the determination of appropriate market comparisons. Changes in these factors and assumptions used can materially affect the amount of impairment loss recognized in the period the asset or asset group was considered impaired. Leases The Company leases certain office, laboratory and manufacturing spaces. In addition to minimum rent, the leases require payment of real estate taxes, insurance, common area maintenance charges and other executory costs. At inception of a contract, the Company determines whether an arrangement is or contains a lease based on the unique facts and circumstances present in the arrangement. For all leases, the Company determines the classification of the lease as either operating or financing. As of December 31, 2025 and 2024, all of the Company’s leases were classified as operating leases. The Company recognizes right-of-use (“ROU”) assets and lease liabilities at the lease commencement date based on the present value of future lease payments over the lease term. As the Company’s leases do not provide an implicit rate, an incremental borrowing rate at each lease commencement date is used to determine the present value of future lease payments. The incremental borrowing rate is the rate of interest that the Company would pay to borrow equivalent funds on a collateralized basis at the lease commencement date. To estimate the incremental borrowing rate, a credit rating applicable to the Company is estimated using a synthetic credit rating analysis since the Company does not currently have a rating agency-based credit rating. The ROU asset includes any lease payments made prior to the lease commencement date and is reduced by any lease incentives received or deemed payable to the Company. The lease term may include options to extend or terminate the lease when it is reasonably certain that a lease option will be exercised. Lease expense is recognized on a straight-line basis over the lease term within operating expenses on the consolidated statements of operations and comprehensive loss. The Company has elected the practical expedient to not separate lease and non-lease components for real estate leases. Additionally, the Company has elected the short-term lease recognition exemption for all short-term leases and as a result, lease liabilities and ROU assets are not included on the consolidated balance sheets for leases with an initial term of 12 months or less. The Company evaluates lease arrangements for impairment whenever events or changes in circumstances indicate that the carrying amounts of the right-of-use asset may not be fully recoverable. To the extent an impairment of the right-of-use asset is identified, the Company recognizes a lease impairment and subsequently amortizes the remaining lease asset on a straight-line basis (unless another systematic basis is more representative of the pattern in which the Company expects to consume the future economic benefits from the asset) from the date of impairment to the earlier of the right‑of‑use asset’s useful life or the end of the lease term. Fair Value Measurements The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. The fair value hierarchy prioritizes valuation inputs based on the observable nature of those inputs. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The hierarchy defines three levels of valuation inputs: Level 1 – Quoted prices in active markets for identical assets or liabilities. Level 2 – Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 3 – Unobservable inputs that reflect the Company’s own assumptions about the assumptions market participants would use in pricing the asset or liability. The Company’s financial instruments, in addition to those presented in Note 8, Fair Value Measurements, include cash, restricted cash, other investments, accounts payable and accrued liabilities and other current liabilities. The carrying amount of cash, restricted cash, accounts payable and accrued liabilities and other current liabilities approximate fair value because of the short-term nature of these instruments. As described in Note 7, Other Investments, other investments are carried at cost, minus impairment and any changes, plus or minus, resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Research and Development Expense The Company records expense for research and development costs as incurred. Research and development expenses consist of costs incurred by the Company for the discovery and development of its technology platforms and product candidates and includes costs incurred in connection with strategic collaborations, costs to license technology, personnel-related costs, including stock-based compensation expense, facility and technology related costs, research and laboratory expenses, as well as other expenses, which include consulting fees and other costs. Upfront payments and milestones paid to third parties in connection with technology platforms that have not reached technological feasibility and do not have an alternative future use are expensed as incurred. Clinical expenses are a component of research and development expense. The Company accrues and expenses clinical trial services performed by third parties based upon actual work completed in accordance with agreements established with its service providers. The Company estimates the costs through discussions with internal personnel and external service providers as to the progress or stage of completion of services and the agreed-upon fees to be paid for such services. General and Administrative Expense General and administrative costs are expensed as incurred and include personnel-related expenses, including stock-based compensation expense for personnel in executive, legal, finance and other administrative functions, legal costs, transaction costs related to collaboration and licensing agreements, as well as fees paid for accounting and tax services, consulting fees and facilities costs not otherwise included in research and development expenses. Legal costs include those related to corporate, dispute and patent matters. Concentrations of Credit Risk and Off-balance Sheet Risk The Company maintains its cash, cash equivalents and restricted cash with high quality, accredited financial institutions. Restricted cash is cash held in a bank account and is used as collateral associated with the Company’s corporate credit card program as well as collateral for a letter of credit in favor of one of the Company’s landlords. Cash, cash equivalents and restricted cash amounts, at times, may exceed federally insured limits. The Company also makes short-term investments in money market funds, U.S. Treasury securities, U.S. government agency securities and corporate debt securities, which can be subject to certain credit risk. However, the Company mitigates the risks by investing in high‑grade instruments, limiting exposure to any one issuer or type of investment and monitoring the ongoing creditworthiness of the financial institutions and issuers. The Company has not experienced any credit losses in such accounts and does not believe it is exposed to significant risk on these funds. The Company has no off‑balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements. Claims and Contingencies From time to time, the Company may become involved in litigation and proceedings relating to claims arising from the ordinary course of business. The Company accrues a liability if the likelihood of an adverse outcome is probable and the amount is estimable. If the likelihood of an adverse outcome is only reasonably possible (as opposed to probable), or if an estimate is not determinable, the Company provides disclosure of a material claim or contingency. Stock-based Compensation Under ASC 718, the Company measures and recognizes expense for restricted stock units (“RSUs”), performance-based restricted stock units (“PSUs”), employee stock purchases related to the Employee Stock Purchase Plan, stock options, performance awards and contingent milestone payments granted to employees, directors, consultants or other third parties based on the fair value of the awards on the date of grant. Stock-based compensation expense for RSAs, RSUs, stock options and contingent milestone payments are recognized on a straight-line basis over the requisite service period, which is generally the vesting period of the respective award. The Company accounts for forfeitures as they occur. For RSAs, RSUs, certain PSUs and contingent milestone payments, the fair value of the Company’s common stock is used to determine the resulting stock-based compensation expense. The fair value of certain stock options is estimated on the date of grant using a Black-Scholes option pricing model, which requires management to apply judgment and make estimates using inputs including: •Fair Value of Common Stock—The fair value of common stock is based on the closing price as reported on the Nasdaq Global Select Market on the date of grant. •Expected Term—The expected term represents the period that a stock-based award is expected to be outstanding. The Company generally uses the simplified method to determine the expected term, which is based on the average of the time-to-vesting and the contractual life of the option. The Company generally uses the simplified method as provided for under the applicable guidance for entities with a limited history of relevant stock option exercise activity. •Expected Volatility—The expected volatility of stock options is determined by weighting the historical volatility of the Company’s common stock with the historical volatilities of the stock of similar entities within the Company’s industry over a period commensurate with the Company’s expected term assumption. •Risk-Free Interest Rate—The risk-free interest rate is based on the interest rate payable on U.S. Treasury securities in effect at the time of grant for a period that is commensurate with the Company’s expected term assumption. •Expected Dividend—The Company has not historically paid, and does not expect for the foreseeable future to pay a dividend. Therefore, the Company used an expected dividend yield of zero. For awards with performance conditions that vest upon a performance condition being met, compensation expense is recognized for the number of shares expected to be earned after assessing the probability that a certain performance condition will be met and the targeted payout level associated with the performance condition expected to be achieved. At each reporting date, the Company is required to evaluate whether achievement of a performance condition or a contingent milestone payment is probable. Cumulative adjustments are recorded each quarter to reflect the estimated outcome of the performance-related conditions until the date results are determined and settled. If performance conditions are not met or not expected to be met, any compensation expense previously recognized associated with the awards will be reversed. The fair values of the Company’s PSUs and performance-based stock options that have market-based metrics are estimated using Monte Carlo simulations. The Company applies an accelerated attribution method to recognize stock-based compensation expense over the applicable service period for these awards. The number of shares expected to be earned is considered in the grant date valuation; therefore, the expense is not subsequently adjusted to reflect the actual shares ultimately earned. Income Taxes The Company determines its deferred tax assets and liabilities based on the differences between the financial reporting and tax basis of assets and liabilities. The deferred tax assets and liabilities are measured using the enacted tax rates that will be in effect when the differences are expected to reverse. A valuation allowance is recorded when it is more likely than not that the deferred tax asset will not be recovered. The Company applies judgment in the determination of the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The Company recognizes any material interest and penalties related to unrecognized tax benefits in income tax expense. Segments Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business in one operating segment and one reportable segment. Acquisitions The Company evaluates acquisitions of assets and other similar transactions to assess whether or not the transaction should be accounted for as a business combination or asset acquisition by first applying a screen to determine if substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or group of similar identifiable assets. If the screen is met, the transaction is accounted for as an asset acquisition. If the screen is not met, further determination is required as to whether or not the Company has acquired inputs and processes that have the ability to create outputs which would meet the requirements of a business in which case the transaction is accounted for using the acquisition method of accounting, which requires, among other things, that assets acquired and liabilities assumed be recognized at their estimated fair values as of the acquisition date, and that the fair value of acquired intangibles be recorded on the balance sheet. Any excess of the purchase price over the assigned fair values of the net assets acquired is recorded as goodwill in a business combination. If the Company determines an acquisition does not meet the definition of a business combination under the acquisition method of accounting, the transaction is accounted for as an asset acquisition. Direct transaction costs are recognized as part of the cost of an asset acquisition. The cost of an asset acquisition, including transaction costs, is allocated to identifiable assets acquired and liabilities assumed based on a relative fair value basis. Goodwill is not recognized in an asset acquisition. In an asset acquisition, upfront payments allocated to in-process research and development (“IPR&D”) are recorded in acquired in‑process research and development expense if it is determined that there is no alternative future use, and subsequent milestone payments are recorded in research and development expense when achieved for technology that has not yet met product feasibility. Contingent Consideration Contingent consideration relates to the potential payments for achieving certain clinical and/or regulatory milestones. For transactions accounted for as asset acquisitions, the Company records contingent consideration at fair value at the date of the acquisition when deemed probable. Liabilities for contingent consideration are remeasured each reporting period and subsequent changes in fair value are recognized within other (expense) income, net in the consolidated statements of operations and comprehensive loss. The assumptions utilized in the calculation of the fair values include the probability of success and the Company’s stock price. Contingent consideration involves certain assumptions requiring significant judgment and actual results may differ from estimated amounts. Recently Adopted Accounting Pronouncements Derivatives In September 2025, the FASB issued Accounting Standards Update (“ASU”) 2025-07, Derivatives and Hedging (Topic 815) and Revenue from Contracts with Customers (Topic 606). The guidance refines the scope of Topic 815 to clarify which contracts are subject to derivative accounting. The amendments in ASU 2025-07 are effective for fiscal years and interim periods beginning after December 15, 2026, with early adoption permitted. The Company early adopted ASU 2025-07 for fiscal 2025 on a prospective basis and the adoption of this standard did not have a significant impact on the Company’s consolidated financial statements. Income Taxes In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The amendments are effective for annual periods beginning after December 15, 2024 and may be applied either prospectively or retrospectively. The Company adopted ASU 2023-09 for the fiscal 2025 year prospectively with no significant updates. Recently Issued Accounting Pronouncements Income Statement Expense Disaggregation In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures, to require more detailed information about specified categories of expenses (purchases of inventory, employee compensation, depreciation and amortization) included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The amendments may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of this ASU or (2) retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on its consolidated financial statements. Interim Reporting In December 2025, the FASB issued ASU 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements, which clarifies the guidance in Topic 270 to improve the consistency of interim financial reporting. The ASU provides a comprehensive list of required interim disclosures and introduces a disclosure principle requiring entities to disclose events since the end of the last annual reporting period that have a material impact on the entity. ASU 2025-11 is effective for fiscal years beginning after December 15, 2027, including interim periods within those fiscal years, with early adoption permitted. The Company is currently evaluating the impact of ASU 2025-11 on its consolidated financial statements.

Income Taxes

12 Months Ended

Dec. 31, 2025

Income Tax Disclosure [Abstract]

Income Taxes

The Company has reported pre-tax operating losses for all periods presented. The Company generated losses in the U.S. and had a minimal amount of income in Israel. The Company has not reflected any benefit for corresponding tax net operating loss carryforwards in the accompanying consolidated financial statements. The Company has established a full valuation allowance against its deferred tax assets due to the uncertainty surrounding the realization of such assets.

Beginning with 2025 annual reporting, the Company adopted ASU 2023-09, Improvements to Income Tax Disclosures, prospectively as described in Note 2, Summary of Significant Accounting Policies. A reconciliation of the U.S. federal statutory income tax rate to the effective tax rate pursuant to the disclosure requirements of ASU 2023-09 for the year ended December 31, 2025 was as follows (in thousands, except percentages):


	Year Ended December 31, 2025
U.S. federal statutory tax	$	(57,634)	21.00	%
Change in valuation allowance	53,781		(19.60)
Nontaxable or nondeductible items
Stock-based compensation	5,830		(2.12)
Fair value adjustment on PIPE	4,029		(1.47)
Other nondeductible items	(2,314)		0.84
R&D Tax credits	(3,563)		1.30
Worldwide changes in UTB	(115)		0.04
Other	(14)		0.01
Effective income tax rate	$	—	0.00	%

A reconciliation of income taxes computed using the U.S. federal statutory rate to that reflected in operations was as follows:


	Year Ended December 31,
	2024		2023
U.S. federal statutory tax	21.00	%	21.00	%
State tax, net of federal benefit	4.61		7.45
Change in valuation allowance	(20.39)		(29.10)
Stock-based compensation	(2.17)		(2.25)
Tax credits	2.23		2.96
IPR&D	(5.34)		—
Other	0.06		(0.06)
Effective income tax rate	0.00	%	0.00	%

The principal components of the Company’s net deferred tax assets were as follows (in thousands), noting certain prior year items were reclassified to conform to the current year presentation:


	Year Ended December 31,
	2025		2024
Deferred tax assets:
Net operating loss carryforward	$	242,841	$	176,298
Tax credit carryforward	42,501		37,611
Capital loss carryforward	14,585		14,705
Accrued liabilities and allowances	3,070		3,818
Property and equipment	10,758		10,551
Intangibles capitalized for tax	30,107		5,582
Capitalized research and development	59,709		82,389
Investment basis difference	7,761		7,820
Lease liability	14,134		16,486
Stock-based compensation	7,893		10,036
Other	819		1,061
Gross deferred tax assets	434,178		366,357
Valuation allowance	(428,947)		(359,440)
Deferred tax assets, net of valuation allowance	5,231		6,917
Deferred tax liabilities:
Operating lease right-of-use assets	(5,231)		(6,917)
Deferred tax liabilities	(5,231)		(6,917)
Net deferred tax assets	$	—	$	—

The changes in the Company’s valuation allowance were as follows (in thousands):


	Year Ended December 31,
	2025		2024
Beginning balance	$	359,440	$	248,420
Change charged to income tax expense	69,507		111,020
Ending balance	$	428,947	$	359,440

The One Big Beautiful Bill Act (“OBBBA”) enacted on July 4, 2025, introduced notable changes to the U.S. Internal Revenue Code, including immediate expensing of domestic Section 174 costs. Section 174 costs are expenditures which represent research and development costs that are incident to the development or improvement of a product, process, formula, invention, computer software or technique. As previously required under the Tax Cuts and Jobs Act, the Company capitalized research and development expenditures in the years ended December 31, 2022 through December 31, 2024. With the enactment of OBBBA, the Company began deducting Section 174 costs in 2025. As of December 31, 2025, the Company has a deferred tax asset of $59.7 million related to capitalized Section 174 expenditures.

As of December 31, 2025 and 2024, the Company had U.S. federal net operating loss (“NOL”) carryforwards of approximately $868.6 million and $599.2 million, respectively, which were available to reduce future taxable income and do not expire. The Company also had U.S. state NOL carryforwards of $876.5 million that begin to expire in 2038 and foreign carryforwards of $7.5 million that do not expire. The Company had gross U.S. federal and state tax credits of $48.6 million and $43.6 million as of December 31, 2025 and 2024, respectively, which may be used to offset future tax liabilities. The federal NOL carryforward period is indefinite, while the tax credits will begin to expire in 2039. The attributed carryforwards may become subject to annual limitations in the event of certain cumulative changes in the ownership interest of significant stockholders. This could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. As of both December 31, 2025 and 2024, the Company had a capital loss carryforward of $52.5 million, which will expire in 2028.

The Company maintains a full valuation allowance on its net U.S. deferred tax assets. The assessment regarding whether a valuation allowance is required considers the evaluation of both positive and negative evidence when concluding

whether it is more likely than not that deferred tax assets are realizable. In making this assessment, significant weight is given to evidence that can be objectively verified. In its evaluation, the Company considered its cumulative loss in recent years and its forecasted losses in the near-term as significant negative evidence. Based upon a review of the four sources of income identified within ASC 740, Accounting for Income Taxes (“ASC 740”), the Company determined that the negative evidence outweighed the positive evidence and a full valuation allowance on its U.S. net deferred tax assets will be maintained. The valuation allowance relates primarily to net U.S. deferred tax assets from net operating loss carryforwards, research and development tax credit carryforwards, research and development expenses and intangibles capitalized and amortized for tax but deducted for GAAP. The Company will continue to assess the realizability of its deferred tax assets and adjust the valuation allowance as required by ASC 740.

In connection with the October 2024 acquisition of ImmPACT stock, the Company recorded U.S. deferred tax assets of $39.6 million, which are mainly related to capitalized research costs and tax attribute carryforwards. The deferred tax assets were considered not more likely than not to be realized and therefore were fully offset by a valuation allowance of $39.6 million.

As of December 31, 2025 and 2024, the Company has an Israeli subsidiary with deferred tax assets of $1.8 million and $1.4 million, respectively, which are mainly related to tax attribute carryforwards. These deferred tax assets are also fully offset by a valuation allowance. The U.S. Company is not dependent on repatriation from its foreign operations to support its liquidity needs. The undistributed earnings of the Company’s foreign operations are intended to be permanently reinvested in those operations. U.S. income taxes have not been recognized on any undistributed earnings that are intended to be permanently reinvested. It is not practical at this time to estimate the additional tax that may become payable upon the eventual repatriation of these amounts, but it is not expected to be material.

The Company evaluates its uncertain tax positions based on a determination of whether it is more likely than not such position will be sustained based upon its technical merits and upon examination by the relevant income tax authorities with all facts known. The Company applies judgment in its measurement of an uncertain tax position recorded in its consolidated financial statements and tax return.

As of December 31, 2025 and 2024, the Company has an unrecognized tax benefit (“UTB”) of $3.5 million and $3.7 million, respectively, as a reduction to the deferred tax asset. If recognized, it would have no impact to our effective tax rate as we have a full valuation allowance. There are no penalties or accrued interest recorded in the consolidated financial statements.

The following table summarized changes to the Company’s unrecognized tax benefits (in thousands):


	Year Ended December 31,
	2025		2024
Beginning balance	$	3,659	$	400
Additions based on tax position related to the current year	—		1,625
Adjustments based on prior year tax positions	(202)		1,634
Ending balance	$	3,457	$	3,659

The Company files income tax returns in the U.S. federal, various state jurisdictions and Israel. The Company is generally subject to examination by the U.S. federal and local income tax authorities for all tax years in which a loss carryforward is available. The Company is currently not under examination by the Internal Revenue Service or other jurisdictions for any tax years.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478822/944-740-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 12
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-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 5: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12C

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12B

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477891/740-270-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/740/tableOfContent

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-14

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-21

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-17

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-2

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Other Investments	12 Months Ended
Other Investments	Dec. 31, 2025
Investments, All Other Investments [Abstract]
Other Investments	Other Investments In prior years the Company made minority ownership strategic investments. As of both December 31, 2025 and 2024, the aggregate carrying amount of the Company’s strategic investments in non-publicly traded companies was $19.0 million. These investments are measured at initial cost, minus impairment, if any, and plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Cumulative impairments of strategic investments in equity investments without readily determinable fair values still held as of both December 31, 2025 and 2024 were $23.0 million, reflecting the full impairment of two of the Company’s other investments. As a part of the acquisition of each of the Company’s other investments, the Company determines whether an investment or other interest is considered a variable interest. As of both December 31, 2025 and 2024, the Company held an interest in one entity that was concluded to be a variable interest for which the Company was not the primary beneficiary as the Company did not have the power to direct the activities that most significantly impact the economic performance of the variable interest entity. As of both December 31, 2025 and 2024, the carrying value and maximum exposure to loss of the Company’s variable interests were zero. During the years ended December 31, 2025, 2024 and 2023, the Company performed qualitative assessments of potential indicators of impairment. For the years ended December 31, 2024 and 2023, the Company determined that indicators existed for certain of its other investments with carrying amounts of $13.0 million and $12.9 million, respectively. While no single event or factor was solely responsible for the impairments in each year, the Company considered the underlying companies’ operating cash flow requirements over the next year, liquid asset balances to fund those requirements and the underlying companies’ inability to raise funds as indicators of impairment. Due to these indicators, the Company assessed the valuation of these investments and determined the fair values to be negligible and the impairments to be other-than-temporary in nature. As a result, the Company recorded impairment expenses of $13.0 million for one investment for the year ended December 31, 2024 and $12.9 million for two investments for the year ended December 31, 2023. No impairment was recorded for the year ended December 31, 2025. The impairment expenses were recorded within impairment of other investments on the consolidated statements of operations and comprehensive loss and as reductions to the investment balances within other investments on the consolidated balance sheets.

Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Oct. 01, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Proceeds from securities purchase agreement equity issuance		$ 50,000	$ 0	$ 0
Equity issued for contingent consideration - ImmPACT Bio USA Inc. acquisition		5,894	0	0
Marketable equity security			30
Impairment of other investments		0	13,001	12,923
Securities Purchase Agreement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Proceeds from securities purchase agreement equity issuance	$ 50,000
Sale of stock, shares required to purchase by purchaser	$ 50,000
ImmPACT Bio USA Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration, shares issued (in shares)	625,000
Equity issued for contingent consideration - ImmPACT Bio USA Inc. acquisition	$ 5,900
Other Investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of other investments		$ 0	$ 13,000	12,900
PACT \| Other Investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable equity security					$ 2,900
Impairment of other investments				$ 2,900

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2025
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Collaboration and License Agreements The Company has entered into certain collaboration and license agreements, including those identified in Note 4, License, Collaboration and Success Payment Agreements above, with third parties that include the funding of certain development, manufacturing and commercialization efforts with the potential for future milestone and royalty payments upon the achievement of pre-established developmental, regulatory and/or commercial milestones. The Company’s obligation to fund these efforts is contingent upon continued involvement in the programs and/or the lack of any adverse events that could cause the discontinuance of the programs, including termination of such agreements. Due to the nature of these agreements, the future potential payments are inherently uncertain, and accordingly no amounts had been recorded for the potential future achievement of these targets as of December 31, 2025 and 2024.

Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Financial assets:
Fair Value	$ 236,805	$ 358,553
Marketable equity security		30
Total financial assets	236,805	358,583
Financial liabilities:
SPA put/call	11,411
Contingent consideration payable		7,600
Success payment liabilities	1,242	411
Total financial liabilities	12,653	8,011
U.S. Treasury securities
Financial assets:
Fair Value	176,072	226,271
U.S. government agency securities
Financial assets:
Fair Value	6,533	36,815
Corporate debt securities
Financial assets:
Fair Value	4,434	21,492
Level 1
Financial assets:
Marketable equity security		30
Total financial assets	49,766	74,005
Financial liabilities:
SPA put/call	0
Contingent consideration payable		0
Success payment liabilities	0	0
Total financial liabilities	0	0
Level 1 \| U.S. Treasury securities
Financial assets:
Fair Value	0	0
Level 1 \| U.S. government agency securities
Financial assets:
Fair Value	0	0
Level 1 \| Corporate debt securities
Financial assets:
Fair Value	0	0
Level 2
Financial assets:
Marketable equity security		0
Total financial assets	187,039	284,578
Financial liabilities:
SPA put/call	0
Contingent consideration payable		0
Success payment liabilities	0	0
Total financial liabilities	0	0
Level 2 \| U.S. Treasury securities
Financial assets:
Fair Value	176,072	226,271
Level 2 \| U.S. government agency securities
Financial assets:
Fair Value	6,533	36,815
Level 2 \| Corporate debt securities
Financial assets:
Fair Value	4,434	21,492
Level 3
Financial assets:
Marketable equity security		0
Total financial assets	0	0
Financial liabilities:
SPA put/call	11,411
Contingent consideration payable		7,600
Success payment liabilities	1,242	411
Total financial liabilities	12,653	8,011
Level 3 \| U.S. Treasury securities
Financial assets:
Fair Value	0	0
Level 3 \| U.S. government agency securities
Financial assets:
Fair Value	0	0
Level 3 \| Corporate debt securities
Financial assets:
Fair Value	0	0
Money market funds
Financial assets:
Money market funds	49,766	73,975
Money market funds \| Level 1
Financial assets:
Money market funds	49,766	73,975
Money market funds \| Level 2
Financial assets:
Money market funds	0	0
Money market funds \| Level 3
Financial assets:
Money market funds	$ 0	$ 0

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2025
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Acquisitions - Schedule of Consideration Paid for Merger (Details) - USD ($) $ in Thousands		12 Months Ended
	Oct. 31, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Asset Acquisition [Line Items]
Common Stock		$ 33,972	$ 36,011	$ 0
Contingent consideration payable		$ 0	$ 11,404	$ 0
ImmPACT Bio USA Inc.
Asset Acquisition [Line Items]
Cash	$ 41,913
Common Stock	36,011
Representative holdback	200
Contingent consideration payable	11,404
Company’s capitalizable transaction expenses	4,215
Total consideration paid	93,743
Cash acquired from acquisition	$ 11,900

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Feb. 28, 2024	Jul. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Class of Stock [Line Items]
Preferred stock authorized (in shares)			10,000,000	10,000,000
Preferred stock, par value (in dollars per share)			$ 0.0001	$ 0.0001
Preferred stock outstanding (in shares)			0	0
Common stock authorized (in shares)			500,000,000	500,000,000
Common stock, par value (in dollars per share)			$ 0.0001	$ 0.0001
Common stock outstanding (in shares)			21,251,353	14,743,777
Proceeds from sale of stock			$ 50,000	$ 0	$ 0
Securities Purchase Agreement
Class of Stock [Line Items]
Sale of stock, sold and issued (in shares)		3,753,752
Sale of stock, price per share (in dollars per share)		$ 13.32
Proceeds from sale of stock		$ 50,000
Sale of stock, shares required to purchase by purchaser		$ 50,000
Sale of stock, shares required to purchase by purchaser, achieved milestone event, period		12 months
Sale of stock, shares required to purchase by purchaser, achieved milestone event, price per share (in dollars per share)		$ 25.61
Sale of stock, shares required to purchase by purchaser, achieved milestone event, minimum price per share (in dollars per share)		$ 10.41
Sale of stock, purchase option by purchaser, achieved milestone event, notice period		40 days
Sale of stock, purchase option by purchaser, achieved milestone event, price per share (in dollars per share)		$ 30.73
Cowen and Company, LLC \| At The Market Offering
Class of Stock [Line Items]
Sale of stock, maximum aggregate offering amount	$ 150,000
Commissions payment, percentage of gross sale proceeds	3.00%

Consolidated Statements of Stockholders’ Equity - USD ($)
$ in Thousands

Total

Common Stock

Additional Paid-in Capital

Accumulated Other Comprehensive Income (Loss)

Accumulated Deficit

Beginning balance, (in shares) at Dec. 31, 2022

^[1]

12,479,000

Beginning balance at Dec. 31, 2022

^[1]

$ 833,252

$ 1

$ 1,608,330

$ (7,599)

$ (767,480)

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Stock-based compensation

47,084

Issuance of common stock upon exercise of stock options (in shares)

150,000

Issuance of common stock upon exercise of stock options

306

Issuance of common stock under employee stock purchase plan (in shares)

49,000

Issuance of common stock under employee stock purchase plan

1,894

Issuance of common stock in connection with restricted stock units, net of tax (in shares)

20,000

Issuance of common stock in connection with restricted stock units, net of tax

(457)

Other comprehensive (loss) income

7,505

Net loss

(234,632)

Ending balance, (in shares) at Dec. 31, 2023

^[1]

12,698,000

Ending balance at Dec. 31, 2023

^[1]

654,952

$ 1

1,657,157

(94)

(1,002,112)

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Stock-based compensation

33,144

Issuance of common stock upon exercise of stock options (in shares)

62,000

Issuance of common stock upon exercise of stock options

154

Issuance of common stock under employee stock purchase plan (in shares)

48,000

Issuance of common stock under employee stock purchase plan

1,248

Issuance of common stock in connection with restricted stock units, net of tax (in shares)

61,000

Issuance of common stock in connection with restricted stock units, net of tax

(76)

Issuance of common stock as payment for acquisition of IPR&D asset (in shares)

1,875,000

Issuance of common stock for acquisition of IPR&D

36,011

Other comprehensive (loss) income

385

Net loss

$ (342,994)

(342,994)

Ending balance, (in shares) at Dec. 31, 2024

14,743,777

14,744,000

^[1]

Ending balance at Dec. 31, 2024

^[1]

$ 382,824

$ 1

1,727,638

291

(1,345,106)

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Stock-based compensation

$ 41,829

41,829

Issuance of common stock upon exercise of stock options (in shares)

3,750

3,000

Issuance of common stock upon exercise of stock options

$ 42

Issuance of common stock under employee stock purchase plan (in shares)

52,000

Issuance of common stock under employee stock purchase plan

365

Issuance of common stock in connection with restricted stock units, net of tax (in shares)

173,000

Issuance of common stock in connection with restricted stock units, net of tax

(1)

Issuance of common stock in connect with contingent consideration milestone (in shares)

625,000

Issuance of common stock in connect with contingent consideration milestone

5,894

Issuance of common stock in connection with PIPE financing (in shares)

3,754,000

Issuance of common stock in connection with PIPE financing

57,774

$ 1

57,773

Issuance of common stock as payment for acquisition of IPR&D asset (in shares)

1,900,000

Issuance of common stock for acquisition of IPR&D

33,972

Other comprehensive (loss) income

(49)

Net loss

$ (274,448)

(274,448)

Ending balance, (in shares) at Dec. 31, 2025

21,251,353

21,251,000

Ending balance at Dec. 31, 2025

$ 248,202

$ 2

$ 1,867,512

$ 242

$ (1,619,554)

[1]	1. Amounts previously reported have been retroactively adjusted to reflect the 1-for-20 reverse stock split effected on May 30, 2025. See Note 2

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
Cybersecurity Risk Management and Strategy Disclosure	Dec. 31, 2025
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	We rely on information technology and data to operate our business and develop and advance our pipeline of product candidates. Our critical information technology includes computer networks, third-party hosted services, communications systems, software and infrastructure, and our critical data includes confidential, personal, proprietary and sensitive data (collectively, Information Assets). Accordingly, we maintain certain risk assessment processes intended to identify cybersecurity threats, determine their likelihood of occurring and assess potential material impact to our business. Based on our assessment, we implement and maintain risk management processes designed to protect the confidentiality, integrity and availability of our Information Assets and mitigate harm to our business. Risks from cybersecurity threats are among those that we review and address in our general risk management program. We identify such threats by, among other things, monitoring the threat environment using manual and automated tools, subscribing to reports and services that identify cybersecurity threats, analyzing reports of threats and actors, conducting scans of the threat environment, evaluating our and our industry’s risk profile, evaluating threats reported to us, conducting threat assessments for internal and external threats and conducting vulnerability assessments to identify vulnerabilities. We rely on a multidisciplinary team (including from our information security function, management and third‑party service providers, as described further below) to assess how cybersecurity threats could impact our business. We routinely assess the likelihood that such threats could result in a material impact to our Information Assets, business and clinical operations, core business functions, personnel, reputation and identified critical business objectives. Based on our assessment process and depending on the environment, we implement and maintain various technical, physical and organizational measures designed to manage and mitigate material risks from cybersecurity threats to our Information Assets, including, for example: policies and procedures designed to address cybersecurity threats, including an incident response plan, disaster recovery and business continuity plans; incident detection and response; internal and/or external audits to assess our exposure to cybersecurity threats, compliance with risk mitigation procedures and effectiveness of relevant controls; documented risk assessments; background checks on our personnel; encryption of data; network security controls; access controls; physical security; asset management; systems monitoring; employee training; penetration testing; and cyber insurance. We prioritize our efforts based on the threats that we believe are more likely to lead to a material impact to our business, such as ransomware, theft of intellectual property and interruption of services and processes on which we rely. We work with third parties that assist us to identify, assess and manage cybersecurity risks, including professional services firms, cybersecurity consultants, cybersecurity software providers, managed cybersecurity service providers and penetration testing firms. To operate our business, we utilize certain third‑party service providers to perform a variety of functions, such as outsourced business functions, professional services, software-as-a-service platforms, managed services, property management, cloud-based infrastructure, data center facilities, encryption and authentication technology and corporate productivity services. Depending on the nature of the services provided, the sensitivity and quantity of information processed and the identity of the service provider, our vendor management process may include reviewing the cybersecurity practices of such provider, contractually imposing obligations on the provider related to the services they provide and/or the information they process, conducting security assessments, conducting on-site inspections and requiring their completion of written questionnaires regarding their cybersecurity programs. For additional information about the risks from cybersecurity threats that may materially affect us and how they may do so, see the section entitled “Risk Factors” in Part I, Item 1A of this Annual Report on Form 10-K, including “If our information technology systems or those third parties with whom we work, or our data, are or were compromised, we could experience adverse consequences resulting from such compromise, including but not limited to regulatory investigations or actions, litigation, fines and penalties, disruptions of our business operations, reputational harm and other adverse consequences.”
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	We rely on information technology and data to operate our business and develop and advance our pipeline of product candidates. Our critical information technology includes computer networks, third-party hosted services, communications systems, software and infrastructure, and our critical data includes confidential, personal, proprietary and sensitive data (collectively, Information Assets). Accordingly, we maintain certain risk assessment processes intended to identify cybersecurity threats, determine their likelihood of occurring and assess potential material impact to our business. Based on our assessment, we implement and maintain risk management processes designed to protect the confidentiality, integrity and availability of our Information Assets and mitigate harm to our business.
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	Our board of directors has overall responsibility for evaluating key business risks faced by us, including cyber security and information technology.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	The audit committee of our board of directors assists the board of directors in the oversight and assessment of risks relating to data privacy, technology and information security, including cybersecurity.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	Our audit committee holds regular meetings to discuss issues including our cybersecurity threats and has a dedicated agenda during such meetings that are designed to assist our board of directors and our audit committee in exercising their oversight function.
Cybersecurity Risk Role of Management [Text Block]	Our cybersecurity risk management strategy relies on input from management, including our Chief Operating Officer, Mr. Stephen Hill, to help us understand cybersecurity risks, establish priorities and determine the scope and details of our cybersecurity program and to implement it. Mr. Hill has held senior management positions at numerous pharmaceutical companies for over a decade. Management is responsible for hiring appropriate personnel, integrating cybersecurity considerations into our overall risk management strategy and for communicating key priorities to employees and other stakeholders. Our cybersecurity incident response and vulnerability management processes involve management, who participate in our disclosure controls and procedures. Management meets regularly to discuss cybersecurity risk and to review our cybersecurity program. Management is also responsible for approving budgets, helping prepare for cybersecurity incidents, responding to cybersecurity incidents, approving cybersecurity policies and procedures, reviewing audit reports and reporting to our board of directors, testing incident response plans and engaging vendors that provide cybersecurity services. Management participates in cybersecurity incident response efforts by being members of the incident response team and helping direct our response to cybersecurity incidents.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	Our cybersecurity risk management strategy relies on input from management, including our Chief Operating Officer, Mr. Stephen Hill, to help us understand cybersecurity risks, establish priorities and determine the scope and details of our cybersecurity program and to implement it.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Mr. Hill has held senior management positions at numerous pharmaceutical companies for over a decade.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	Our board of directors has overall responsibility for evaluating key business risks faced by us, including cyber security and information technology. The audit committee of our board of directors assists the board of directors in the oversight and assessment of risks relating to data privacy, technology and information security, including cybersecurity. Our audit committee holds regular meetings to discuss issues including our cybersecurity threats and has a dedicated agenda during such meetings that are designed to assist our board of directors and our audit committee in exercising their oversight function. The meetings involve presentations and reports from our management and specifically include updates of current cybersecurity threats faced by us and steps we are taking to address them.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

Related-Party Transactions

12 Months Ended

Dec. 31, 2025

Related-Party Transactions

In September 2021, the Company entered into a sublease with Sonoma (“Sonoma Sublease”), with whom the Company has common stockholders with board seats, whereby the Company agreed to sublease approximately 18,000 square feet of space in South San Francisco, California currently leased by the Company. Dr. Klausner, the Chair of the Company’s board of directors, also serves as Board Chair of the board of directors of Sonoma. As a part of the Sonoma Sublease, a $4.6 million tenant improvement contribution payment was made by Sonoma, which is recognized over the term of the Sonoma Sublease. As of December 31, 2025 and 2024, there were accrued liabilities and other current liabilities of $2.5 million and $0.5 million, respectively, and as of December 31, 2025 and 2024, there were other non-current liabilities of zero and $2.5 million, respectively, in connection with the Sonoma Sublease. Total operating income from Sonoma and income solely attributable to the Sonoma Sublease are shown in the table below (in thousands). Total operating income includes income attributable to the sublease, as well as additional operating fees recognized in “other operating income, net” such as common area maintenance charges. See Note 11, Leases, for more detail on the Sonoma Sublease.


	Year Ended December 31,
	2025		2024		2023
Sonoma other operating income, net	$	2,740	$	2,838	$	2,592
Sonoma sublease income	$	1,861	$	1,861	$	1,861

In connection with the SPA, ARCH Venture XIII, L.P. participated as a Purchaser by acquiring approximately 0.9 million shares of common stock for aggregate gross proceeds to the Company of $12.5 million at a purchase price of $13.32 per share. ARCH Venture Fund XIII, L.P. filed a Form 3 in July 2025 stating it beneficially owned greater than 10% of the Company’s outstanding common stock as of that date. See Note 13, Stockholders’ Equity, for additional information regarding the SPA.

- 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.

+ References

Reference 1: 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 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-5

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 7: 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)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 8: 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))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 9: 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)(e))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

+ Details

License, Collaboration and Success Payment Agreements - Schedule of Aggregate Potential Success Payments (Details) - Collaborative Arrangement, Transaction with Party to Collaborative Arrangement	Dec. 31, 2025 USD ($)	Oct. 31, 2020 USD ($) $ / shares	Dec. 31, 2018 USD ($) $ / shares
Fred Hutch
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Aggregate success payment(s) (in millions)	$ 0
Stanford
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Aggregate success payment(s) (in millions)	$ 0
Ten Times \| Fred Hutch
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance			10
Per share common stock price required for payment (in dollars per share) \| $ / shares			$ 365.76
Aggregate success payment(s) (in millions)			$ 10,000,000
Ten Times \| Stanford
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance		10
Per share common stock price required for payment (in dollars per share) \| $ / shares		$ 365.76
Aggregate success payment(s) (in millions)		$ 10,000,000
Twenty Times \| Fred Hutch
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance			20
Per share common stock price required for payment (in dollars per share) \| $ / shares			$ 731.52
Aggregate success payment(s) (in millions)			$ 40,000,000
Twenty Times \| Stanford
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance		20
Per share common stock price required for payment (in dollars per share) \| $ / shares		$ 731.52
Aggregate success payment(s) (in millions)		$ 40,000,000
Thirty Times \| Fred Hutch
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance			30
Per share common stock price required for payment (in dollars per share) \| $ / shares			$ 1,097.28
Aggregate success payment(s) (in millions)			$ 90,000,000
Thirty Times \| Stanford
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance		30
Per share common stock price required for payment (in dollars per share) \| $ / shares		$ 1,097.28
Aggregate success payment(s) (in millions)		$ 90,000,000
Forty Times \| Fred Hutch
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance			40
Per share common stock price required for payment (in dollars per share) \| $ / shares			$ 1,463.04
Aggregate success payment(s) (in millions)			$ 140,000,000
Forty Times \| Stanford
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance		40
Per share common stock price required for payment (in dollars per share) \| $ / shares		$ 1,463.04
Aggregate success payment(s) (in millions)		$ 140,000,000
Fifty Times \| Fred Hutch
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance			50
Per share common stock price required for payment (in dollars per share) \| $ / shares			$ 1,828.8
Aggregate success payment(s) (in millions)			$ 200,000,000
Fifty Times \| Stanford
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Multiple of initial equity value at issuance		50
Per share common stock price required for payment (in dollars per share) \| $ / shares		$ 1,828.8
Aggregate success payment(s) (in millions)		$ 200,000,000

Leases - Narrative (Details) $ in Thousands	12 Months Ended
Leases - Narrative (Details) $ in Thousands	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2019 ft² option contract	Oct. 31, 2024 ft² option	Sep. 30, 2024 ft²	Sep. 30, 2021 USD ($) ft²	May 31, 2021 ft²	Dec. 31, 2018 ft² option
Lessee, Lease, Description [Line Items]
Operating lease cost \| $	$ 9,100	$ 9,200	$ 9,000
Variable lease cost \| $	$ 6,900	$ 7,100	5,400
Weighted average remaining lease term of operating leases (in years)	4 years 9 months 18 days	5 years 8 months 12 days
Operating lease, weighted average discount rate (as a percent)	8.50%	8.50%
Sonoma sublease income \| $	$ 3,601	$ 3,004	2,729
Impairment of long-lived assets \| $	1,443	51,297	0
South San Francisco, California
Lessee, Lease, Description [Line Items]
Rentable area (in square feet) \| ft²						12,150		11,000
Related Party
Lessee, Lease, Description [Line Items]
Rentable area (in square feet) \| ft²							18,000
Related Party \| Sonoma
Lessee, Lease, Description [Line Items]
Rentable area (in square feet) \| ft²							18,000
Sonoma sublease income \| $	$ 1,861	1,861	1,861
Tenant improvements \| $							$ 4,600
Building \| ImmPACT Bio USA Inc.
Lessee, Lease, Description [Line Items]
Area of space (in square feet) \| ft²					26,000
Renewal term (in years)					5 years
Number of options to extend the lease \| option					1
Building \| Expires in December 2028
Lessee, Lease, Description [Line Items]
Area of space (in square feet) \| ft²									34,000
Number of renewal options \| option									2
Renewal term (in years)									5 years
Building \| Expires in May 2030
Lessee, Lease, Description [Line Items]
Area of space (in square feet) \| ft²				73,000
Number of renewal options \| option				2
Renewal term (in years)				90 months
Number of operating lease agreements \| contract				2
Building \| Expires In March 2031
Lessee, Lease, Description [Line Items]
Area of space (in square feet) \| ft²				108,000
Renewal term (in years)				10 years
Right Of Use Asset
Lessee, Lease, Description [Line Items]
Impairment of long-lived assets \| $		$ 12,600	$ 0

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (274,448)	$ (342,994)	$ (234,632)
Adjustments to reconcile net loss to net cash used in operating activities:
Acquired IPR&D expense	66,332	87,184	0
Stock-based compensation expense	41,829	33,144	47,084
Loss on securities purchase agreement put/call	19,185	0	0
Depreciation and amortization expense	11,539	19,631	20,250
Net amortization and accretion on marketable securities	(4,959)	(14,681)	(9,596)
Non-cash lease income	(3,550)	(2,198)	(1,873)
Loss on property and equipment disposals, net	3,344	1,341	1,509
Change in fair value of contingent consideration payable	(1,706)	(3,804)	0
Impairment of long-lived assets	1,443	51,297	0
Change in fair value of success payment liabilities	831	(1,165)	(2,780)
Impairment of other investments	0	13,001	12,923
Loss (gain) on marketable equity security	30	(30)	0
Changes in operating assets and liabilities:
Prepaid expenses, other current assets and other assets	2,823	1,775	3,125
Accounts payable	(2,339)	(3,234)	1,464
Accrued liabilities and other current liabilities	(7,642)	(1,250)	(719)
Other non-current liabilities	(2,736)	(411)	(449)
Net cash used in operating activities	(150,024)	(162,394)	(163,694)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of property and equipment	(780)	(464)	(2,686)
Sales of property and equipment	287	0	0
Purchases of marketable securities	(278,899)	(394,707)	(476,880)
Maturities of marketable securities	374,684	548,941	663,614
Acquisition of assets, net of cash acquired	(41,195)	(31,346)	0
Net cash provided by investing activities	54,097	122,424	184,048
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from securities purchase agreement equity issuance	50,000	0	0
Proceeds from exercise of stock options	42	154	306
Proceeds from employee stock purchase plan	365	1,248	1,894
Taxes paid related to net share settlement of equity awards	(1)	(76)	(457)
Net cash provided by financing activities	50,406	1,326	1,743
Net (decrease) increase in cash, cash equivalents and restricted cash	(45,521)	(38,644)	22,097
Cash, cash equivalents and restricted cash at beginning of period	107,287	145,931	123,834
Cash, cash equivalents and restricted cash at end of period	61,766	107,287	145,931
Represented by:
Cash and cash equivalents	60,181	105,597	145,647
Restricted cash	1,585	1,690	284
Total	61,766	107,287	145,931
SUPPLEMENTAL CASH FLOW INFORMATION
Cash paid for amounts included in the measurement of lease liabilities	12,587	11,467	10,845
Non-cash investing and financing activities:
Equity issued for Acquisition (Note 3)	33,972	36,011	0
Securities purchase agreement put/call issuance	7,774	0	0
Equity issued for contingent consideration - ImmPACT Bio USA Inc. acquisition	5,894	0	0
Contingent consideration payable related to the purchase of the IPR&D asset on Closing Date (Note 3 & 8)	0	11,404	0
Purchases of property and equipment included in accounts payable and accrued liabilities	$ 0	$ 144	$ 29

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2025
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

License, Collaboration and Success Payment Agreements - Narrative (Details)

12 Months Ended

Dec. 31, 2025

USD ($)

$ / shares

Dec. 31, 2024

USD ($)

$ / shares

Dec. 31, 2023

USD ($)

$ / shares

Oct. 31, 2020

USD ($)

$ / shares

Dec. 31, 2018

USD ($)

$ / shares

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Reduction in net loss

$ (274,448,000)

$ (342,994,000)

$ (234,632,000)

Reduction in net loss per common share, basic (in dollars per share) | $ / shares

^[1]

$ (16.06)

$ (26.23)

$ (18.70)

Reduction in net loss per common share, diluted (in dollars per share) | $ / shares

^[1]

$ (16.06)

$ (26.23)

$ (18.70)

Impairment of other investments

$ 0

$ 13,001,000

$ 12,923,000

Other Investment

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Impairment of other investments

13,000,000.0

12,900,000

Series A Convertible Preferred Stock

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Convertible preferred stock, par value (in dollars per share) | $ / shares

$ 36.58

Fred Hutch | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Potential aggregate success payments

Term of success payment agreement (in years)

9 years

Trigger period from IPO date (in years)

1 year

Trigger period thereafter (in years)

2 years

Fair value of potential success payments due

400,000

100,000

Success payment expense/(gain)

300,000

(500,000)

(1,900,000)

Fred Hutch | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Minimum

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Multiple of initial equity value at issuance

Potential aggregate success payments

$ 10,000,000.0

Per share common stock price required for payment (in dollars per share) | $ / shares

$ 365.76

Fred Hutch | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Maximum

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Multiple of initial equity value at issuance

Potential aggregate success payments

$ 200,000,000.0

Per share common stock price required for payment (in dollars per share) | $ / shares

$ 1,828.8

Stanford | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Potential aggregate success payments

Term of success payment agreement (in years)

9 years

Trigger period from IPO date (in years)

1 year

Trigger period thereafter (in years)

2 years

Success payment expense/(gain)

500,000

(600,000)

(900,000)

Success payment liability

$ 800,000

$ 300,000

Stanford | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Minimum

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Multiple of initial equity value at issuance

Potential aggregate success payments

$ 10,000,000.0

Per share common stock price required for payment (in dollars per share) | $ / shares

$ 365.76

Stanford | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Maximum

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Multiple of initial equity value at issuance

Potential aggregate success payments

$ 200,000,000.0

Per share common stock price required for payment (in dollars per share) | $ / shares

$ 1,828.8

PACT | Other Investment

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Impairment of other investments

$ 2,900,000

[1]	1. Amounts previously reported have been retroactively adjusted to reflect the 1-for-20 reverse stock split effected on May 30, 2025. See Note 2.

Other Investments (Details) $ in Thousands	12 Months Ended
Other Investments (Details) $ in Thousands	Dec. 31, 2025 USD ($) entity	Dec. 31, 2024 USD ($) entity	Dec. 31, 2023 USD ($)
Schedule of Investments [Line Items]
Other investments	$ 19,000	$ 19,000
Variable interest entity, number of entities company is not primary beneficiary \| entity	1	1
Variable interest entity maximum loss exposure, amount	$ 0	$ 0
Impairment of other investments	0	13,001	$ 12,923
Variable Interest Entity, Not Primary Beneficiary
Schedule of Investments [Line Items]
Other investments	0	0
Other Investment
Schedule of Investments [Line Items]
Cumulative impairments of strategic investments	23,000	23,000
Impairment of other investments	$ 0	$ 13,000	$ 12,900

- 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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-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 19
-Subparagraph (3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477271/946-320-S99-19

+ Details

Property and Equipment, Net

12 Months Ended

Dec. 31, 2025

Property, Plant and Equipment [Abstract]

Property and Equipment, Net

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


	December 31,
	2025		2024
Leasehold improvements	$	79,739	$	79,613
Laboratory equipment	26,372		36,106
Computer equipment and software	1,672		1,805
Furniture and fixtures	814		1,114
Construction in progress	452		241
Property and equipment, at cost	109,049		118,879
Less: Accumulated depreciation and amortization	(74,278)		(70,679)
Total property and equipment, net	$	34,771	$	48,200

Depreciation and amortization expense was $10.4 million, $19.4 million and $20.2 million for the years ended December 31, 2025, 2024 and 2023, respectively.

During the year ended December 31, 2024, the Company recorded impairment losses of $38.7 million for leasehold improvements. The Company did not record any impairment losses related to leasehold improvements in 2025 or 2023. See Note 5, Impairment of Long‑Lived Assets, for further information.

Income Taxes - Narrative (Details) - USD ($)	Dec. 31, 2025	Dec. 31, 2024	Oct. 31, 2024	Dec. 31, 2023
Income Tax Examination [Line Items]
Capitalized research and development	$ 59,709,000	$ 82,389,000
Gross deferred tax assets	434,178,000	366,357,000
Deferred tax assets, valuation allowance	428,947,000	359,440,000		$ 248,420,000
Uncertain tax positions	3,457,000	3,659,000		$ 400,000
Penalties or interest accrued on income taxes	0	0
ImmPACT Bio USA Inc.
Income Tax Examination [Line Items]
Gross deferred tax assets			$ 39,600,000
Deferred tax assets, valuation allowance			$ 39,600,000
Deferred tax assets, foreign tax attribute carryforwards	1,800,000	1,400,000
Tax Year 2028 \| Capital Loss Carryforward
Income Tax Examination [Line Items]
Tax credit carryforwards	52,500,000
Federal and State
Income Tax Examination [Line Items]
Tax credit carryforwards	48,600,000	43,600,000
Federal
Income Tax Examination [Line Items]
Operating loss carryforwards not subject to expiration	868,600,000	$ 599,200,000
State
Income Tax Examination [Line Items]
Operating loss carryforwards subject to expiration	876,500,000
Foreign Tax Jurisdiction
Income Tax Examination [Line Items]
Operating loss carryforwards not subject to expiration	$ 7,500,000

Employee Benefit Plan (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefit Plan (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Retirement Benefits [Abstract]
Defined contribution, employer contribution amount	$ 0.8	$ 1.0	$ 1.2

Stock-based Compensation - Schedule of Stock-Based Compensation Expense by Classification (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	$ 41,829	$ 33,144	$ 47,084
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	28,743	14,577	18,207
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	$ 13,086	$ 18,567	$ 28,877

Cash Equivalents and Marketable Securities

12 Months Ended

Dec. 31, 2025

Cash and Cash Equivalents [Abstract]

Cash Equivalents and Marketable Securities

The fair value and amortized cost of cash equivalents and fixed income marketable securities by major security type are as follows (in thousands):


	December 31, 2025
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	$	49,766	$	—	$	—	$	49,766
U.S. Treasury securities	175,839		233		—		176,072
U.S. government agency securities	6,528		5		—		6,533
Corporate debt securities	4,430		4		—		4,434
Total cash equivalents and fixed income marketable securities	$	236,563	$	242	$	—	$	236,805


Classified as:	Fair Value
Cash equivalents	$	49,766
Marketable securities	187,039
Marketable securities, non-current	—
Total cash equivalents and fixed income marketable securities	$	236,805


	December 31, 2024
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	$	73,975	$	—	$	—	$	73,975
U.S. Treasury securities	226,049		262		(40)		226,271
U.S. government agency securities	36,765		51		(1)		36,815
Corporate debt securities	21,473		20		(1)		21,492
Total cash equivalents and fixed income marketable securities	$	358,262	$	333	$	(42)	$	358,553


Classified as:	Fair Value
Cash equivalents	$	80,639
Marketable securities	264,900
Marketable securities, non-current	13,014
Total cash equivalents and fixed income marketable securities	$	358,553

The fair values of money market and fixed income marketable securities held by the Company in an unrealized loss position for less than 12 months were zero and $31.7 million, as of December 31, 2025 and 2024, respectively. The fair values of money market and fixed income marketable securities held by the Company in an unrealized loss position for greater than 12 months were zero as of both December 31, 2025 and 2024. As of December 31, 2025 and 2024, all of the Company’s money market and fixed income marketable securities had a maturity date of two years or less, were available

for use and were classified as available-for-sale. The Company does not intend to sell these securities nor does the Company believe that it will be required to sell these securities before recovery of their amortized cost basis. The Company determined that there was no material change in the credit risk of the above investments as of both December 31, 2025 and 2024. As such, an allowance for credit losses has not been recognized. Gross realized gains and losses were de minimis for the years ended December 31, 2025 and 2024 and as a result, amounts reclassified out of accumulated other comprehensive loss for the years ended December 31, 2025 and 2024 were also de minimis. See Note 8, Fair Value Measurements, for additional information regarding cash equivalents and fixed income marketable securities.

Acquisitions - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Nov. 06, 2025	Oct. 31, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Business Combination [Line Items]
Acquired in-process research and development			$ 66,332	$ 87,184	$ 0
Asset acquisition, upfront payment			41,195	31,346	$ 0
ICT License Acquisition
Business Combination [Line Items]
Increase (decrease) in prepaid supplies			1,300
Prepaid clinical supply			$ 7,500
Asset acquisition, contingent consideration, possible achievement, issuance of common shares			1,100,000
Asset acquisition, contingent consideration probable achievement, share-based compensation expense			$ 19,700
Acquired in-process research and development	$ 66,300
ImmPACT Bio USA Inc.
Business Combination [Line Items]
Total consideration		$ 93,743
Acquired in-process research and development				$ 87,200
Asset acquisition, upfront payment		30,000
Cash acquired from acquisition		$ 11,900
Stock issued during period, shares, acquisitions (in shares)		1,875,000
Asset acquisition, contingent consideration payable, shares held (in shares)		625,000		625,000
Asset acquisition, equity consideration, price per share (in dollars per share)		$ 19.21
Innovative Cellular Therapeutics Holdings Limited and Innovative Cellular Therapeutics, Inc \| ICT License Acquisition
Business Combination [Line Items]
Prepaid clinical supply cap	10,000
Asset acquisition, upfront cash payment	$ 40,000
Asset acquisition, share issuance (in shares)	1,900,000
Asset acquisition, fair value of equity consideration price per share	$ 17.88
Total consideration	$ 75,200
Asset acquisition, clinical milestone, contingent cash payment	30,000
Asset acquisition, late-stage regulatory milestone, maximum contingent cash payment	115,000
Asset acquisition, commercial sales milestones, maximum contingent cash payment	$ 675,000
Asset acquisition, clinical and regulatory milestones, maximum contingent share issuance	1,850,000
Asset acquisition, tiered royalties, annual net sales, maximum percentage	10.00%
ICT License Acquisition \| ICT License Acquisition
Business Combination [Line Items]
Prepaid clinical supply cap	$ 10,000

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2025

Fair Value Disclosures [Abstract]

Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis


	December 31, 2025
	Level 1		Level 2		Level 3		Total
Financial assets:
Money market funds	$	49,766	$	—	$	—	$	49,766
U.S. Treasury securities	—		176,072		—		176,072
U.S. government agency securities	—		6,533		—		6,533
Corporate debt securities	—		4,434		—		4,434
Total financial assets	$	49,766	$	187,039	$	—	$	236,805
Financial liabilities:
SPA put/call	$	—	$	—	$	11,411	$	11,411
Success payment liabilities	—		—		1,242		1,242
Total financial liabilities	$	—	$	—	$	12,653	$	12,653


	December 31, 2024
	Level 1		Level 2		Level 3		Total
Financial assets:
Money market funds	$	73,975	$	—	$	—	$	73,975
U.S. Treasury securities	—		226,271		—		226,271
U.S. government agency securities	—		36,815		—		36,815
Corporate debt securities	—		21,492		—		21,492
Marketable equity security	30		—		—		30
Total financial assets	$	74,005	$	284,578	$	—	$	358,583
Financial liabilities:
Contingent consideration payable	$	—	$	—	$	7,600	$	7,600
Success payment liabilities	—		—		411		411
Total financial liabilities	$	—	$	—	$	8,011	$	8,011

Schedule of SPA Put/Call is Classified as a Level 3 Financial Instrument and the Fair Value Estimated using a Monte Carlo Simulation Valuation Method

The SPA put/call is classified as a Level 3 financial instrument and the fair value at inception on July 24, 2025 and period-end on December 31, 2025 were estimated using the Monte Carlo simulation valuation method including the following assumptions:


	July 24, 2025		December 31, 2025
Time to maturity (years)	1.11		0.67
Risk-free rate	4.08	%	3.55	%
Volatility	91	%	90	%

Schedule of Changes in the Estimated Fair Value of Level 3 Financial Assets

The following table sets forth a summary of the changes in the fair value of the Company’s Level 3 financial liabilities (in thousands):


	Contingent Consideration Payable		Success Payment Liabilities		SPA put/call (Asset) Liability
Balance at December 31, 2023	$	—	$	1,576	$	—
Issuance	11,404		—		—
Change in fair value (1)	(3,804)		(1,165)		—
Balance at December 31, 2024	7,600		411		—
Issuance	—		—		(7,774)
Change in fair value (1)	(1,706)		831		19,185
Settlement via equity issuance	(5,894)		—		—
Balance at December 31, 2025	$	—	$	1,242	$	11,411

__________

Schedule of Changes in the Estimated Fair Value of Level 3 Financial Liabilities

The following table sets forth a summary of the changes in the fair value of the Company’s Level 3 financial liabilities (in thousands):


	Contingent Consideration Payable		Success Payment Liabilities		SPA put/call (Asset) Liability
Balance at December 31, 2023	$	—	$	1,576	$	—
Issuance	11,404		—		—
Change in fair value (1)	(3,804)		(1,165)		—
Balance at December 31, 2024	7,600		411		—
Issuance	—		—		(7,774)
Change in fair value (1)	(1,706)		831		19,185
Settlement via equity issuance	(5,894)		—		—
Balance at December 31, 2025	$	—	$	1,242	$	11,411

__________

- Definition

Tabular disclosure of the fair value measurement of assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income (loss), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset.

+ References + Details

Leases (Tables)

12 Months Ended

Dec. 31, 2025

Leases [Abstract]

Schedule of Future Minimum Operating Lease Commitments, Including Expected Lease Incentives to be Received

The following table summarizes the Company’s future minimum operating lease commitments, including lease incentives, as of December 31, 2025 (in thousands):


Year Ending December 31:
2026	$	12,959
2027	13,341
2028	13,005
2029	10,398
2030	9,855
Thereafter	2,333
Total undiscounted lease payments	61,891
Less: imputed interest	(10,897)
Total operating lease liabilities	$	50,994

Reported as of December 31, 2025:
Short-term portion of lease liabilities (included in accrued liabilities and other current liabilities)	$	9,073
Operating lease liabilities, non-current	41,921
Total	$	50,994

Schedule of Current and Non-current Lease Liabilities

The following table summarizes the Company’s future minimum operating lease commitments, including lease incentives, as of December 31, 2025 (in thousands):


Year Ending December 31:
2026	$	12,959
2027	13,341
2028	13,005
2029	10,398
2030	9,855
Thereafter	2,333
Total undiscounted lease payments	61,891
Less: imputed interest	(10,897)
Total operating lease liabilities	$	50,994

Reported as of December 31, 2025:
Short-term portion of lease liabilities (included in accrued liabilities and other current liabilities)	$	9,073
Operating lease liabilities, non-current	41,921
Total	$	50,994

Schedule of Total Income Attributable to Sublease

Total operating income from the subleases and income solely attributable to the subleases are shown in the table below (in thousands). Total operating income includes income attributable to the subleases, as well as additional operating fees recognized in other operating income, net such as common area maintenance charges.


	Year Ended December 31,
	2025		2024		2023
Other operating income, net - subleases	$	5,466	$	4,530	$	4,152
Sublease income	$	3,601	$	3,004	$	2,729

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2025

Income Tax Disclosure [Abstract]

Schedule of Reconciliation of Federal Statutory Income Tax Rate

A reconciliation of the U.S. federal statutory income tax rate to the effective tax rate pursuant to the disclosure requirements of ASU 2023-09 for the year ended December 31, 2025 was as follows (in thousands, except percentages):


	Year Ended December 31, 2025
U.S. federal statutory tax	$	(57,634)	21.00	%
Change in valuation allowance	53,781		(19.60)
Nontaxable or nondeductible items
Stock-based compensation	5,830		(2.12)
Fair value adjustment on PIPE	4,029		(1.47)
Other nondeductible items	(2,314)		0.84
R&D Tax credits	(3,563)		1.30
Worldwide changes in UTB	(115)		0.04
Other	(14)		0.01
Effective income tax rate	$	—	0.00	%

A reconciliation of income taxes computed using the U.S. federal statutory rate to that reflected in operations was as follows:


	Year Ended December 31,
	2024		2023
U.S. federal statutory tax	21.00	%	21.00	%
State tax, net of federal benefit	4.61		7.45
Change in valuation allowance	(20.39)		(29.10)
Stock-based compensation	(2.17)		(2.25)
Tax credits	2.23		2.96
IPR&D	(5.34)		—
Other	0.06		(0.06)
Effective income tax rate	0.00	%	0.00	%

Schedule of Deferred Tax Assets

The principal components of the Company’s net deferred tax assets were as follows (in thousands), noting certain prior year items were reclassified to conform to the current year presentation:


	Year Ended December 31,
	2025		2024
Deferred tax assets:
Net operating loss carryforward	$	242,841	$	176,298
Tax credit carryforward	42,501		37,611
Capital loss carryforward	14,585		14,705
Accrued liabilities and allowances	3,070		3,818
Property and equipment	10,758		10,551
Intangibles capitalized for tax	30,107		5,582
Capitalized research and development	59,709		82,389
Investment basis difference	7,761		7,820
Lease liability	14,134		16,486
Stock-based compensation	7,893		10,036
Other	819		1,061
Gross deferred tax assets	434,178		366,357
Valuation allowance	(428,947)		(359,440)
Deferred tax assets, net of valuation allowance	5,231		6,917
Deferred tax liabilities:
Operating lease right-of-use assets	(5,231)		(6,917)
Deferred tax liabilities	(5,231)		(6,917)
Net deferred tax assets	$	—	$	—

Schedule of Changes in Company’s Valuation Allowance

The changes in the Company’s valuation allowance were as follows (in thousands):


	Year Ended December 31,
	2025		2024
Beginning balance	$	359,440	$	248,420
Change charged to income tax expense	69,507		111,020
Ending balance	$	428,947	$	359,440

Schedule of Changes to Company’s Unrecognized Tax Benefits

The following table summarized changes to the Company’s unrecognized tax benefits (in thousands):


	Year Ended December 31,
	2025		2024
Beginning balance	$	3,659	$	400
Additions based on tax position related to the current year	—		1,625
Adjustments based on prior year tax positions	(202)		1,634
Ending balance	$	3,457	$	3,659

Segment

12 Months Ended

Dec. 31, 2025

Segment Reporting [Abstract]

Segment

The Company reports segment information in accordance with the management approach, which reflects the internal reporting utilized by the Chief Operating Decision Maker (“CODM”), the Company’s President and Chief Executive Officer. Based on the information used by the CODM to allocate resources and assess the Company’s performance, the Company has determined it operates in one segment. The CODM reviews financial information presented on a consolidated basis for purposes of making operating decisions and assessing financial performance. Prior period segment information has been recast to reflect the manner in which financial information is currently reviewed by the CODM to allocate resources and assess performance, conforming to the current period presentation.

The CODM evaluates the performance of the Company’s sole reportable segment based on net income or loss that also is reported on the consolidated statements of operations and comprehensive loss as net income or loss. The table below details the Company’s segment net loss, significant expenses, and other segment items (in thousands). The measure of segment assets is reported on the consolidated balance sheets as total assets.


	Year Ended December 31,
	2025		2024		2023
Revenue	$	36	$	61	$	130
Less:
Technical operations	47,202		46,102		49,851
Clinical development	36,671		38,561		27,241
Support functions	25,737		29,870		34,096
Lease costs	16,643		16,885		14,788
Operations management	13,106		14,145		22,814
Research activities	11,038		25,284		33,309
Other segment items(1)	124,087		172,208		52,663
Net loss	$	274,448	$	342,994	$	234,632

1.Includes stock-based compensation, depreciation, other operating income, net, acquired in-process research and development, impairment of long-lived assets, interest income, net, other (expense) income, net, and impairment of other investments.

Total expenditures for additions to the Company’s property and equipment, net were $0.6 million, $0.6 million and $1.4 million for the years ended December 31, 2025, 2024 and 2023, respectively.

The Company’s long-lived assets as of December 31, 2025 and 2024 are located in the United States.

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-21

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-21

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-31

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
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-Topic 280
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
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-Section 55
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
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-Subparagraph (f)
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
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-Paragraph 1
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Reference 11: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 280
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-Topic 280
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26C

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26B

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-40

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
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Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
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Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-41

+ Details

Income Taxes - Schedule of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Deferred tax assets:
Net operating loss carryforward	$ 242,841	$ 176,298
Tax credit carryforward	42,501	37,611
Capital loss carryforward	14,585	14,705
Accrued liabilities and allowances	3,070	3,818
Property and equipment	10,758	10,551
Intangibles capitalized for tax	30,107	5,582
Capitalized research and development	59,709	82,389
Investment basis difference	7,761	7,820
Lease liability	14,134	16,486
Stock-based compensation	7,893	10,036
Other	819	1,061
Gross deferred tax assets	434,178	366,357
Valuation allowance	(428,947)	(359,440)	$ (248,420)
Deferred tax assets, net of valuation allowance	5,231	6,917
Deferred tax liabilities:
Operating lease right-of-use assets	(5,231)	(6,917)
Deferred tax liabilities	(5,231)	(6,917)
Net deferred tax assets	$ 0	$ 0

Stock-based Compensation

12 Months Ended

Dec. 31, 2025

Share-Based Payment Arrangement [Abstract]

Stock-based Compensation

Equity Incentive and Employee Stock Purchase Plans

In June 2021, the Company adopted the 2021 Equity Incentive Plan (“2021 Plan”) and the 2021 Employee Stock Purchase Plan (“2021 ESPP”), both of which became effective on the date of the underwriting agreement related to the Company’s IPO. Under the 2021 Plan, the Company may grant incentive stock options, non-statutory stock options, restricted stock awards (“RSAs”), RSUs, PSUs, stock appreciation rights, performance awards and other stock-based awards. The term of any stock option granted under the 2021 Plan cannot exceed ten years. Generally, stock options (other than performance-based stock options, discussed below) and RSU awards granted by the Company vest over four years,

but may be granted with different vesting terms. PSUs and PBOs generally have a three-year performance period, with vesting subject to the achievement of the associated performance condition. On January 1, 2025, the Company reserved an additional 737,188 shares of common stock for issuance under the 2021 Plan representing 5% of the total common shares outstanding as of December 31, 2024. The Company’s board of directors elected to reserve no additional shares under the 2021 ESPP for the year beginning January 1, 2025.

The 2021 ESPP allows eligible employees to purchase shares of the Company’s common stock at a discount through payroll deductions of up to 15% of their earnings, subject to plan limitations. Unless otherwise determined by the Company’s board of directors, employees are able to purchase shares at 85% of the lower of the fair market value of the Company’s common stock on the first date of an offering or on the purchase date. Under the 2021 ESPP, 51,799, 47,738 and 49,320 shares were issued for the years ended December 31, 2025, 2024 and 2023, respectively.

As of December 31, 2025, 2,105,974 and 200,833 shares were available for future issuance pursuant to the 2021 Plan and the 2021 ESPP, respectively.

Stock-based Compensation Expense

Stock-based compensation expense by classification included within the consolidated statements of operations and comprehensive loss was as follows (in thousands):


	Year Ended December 31,
	2025		2024		2023
Research and development	$	28,743	$	14,577	$	18,207
General and administrative	13,086		18,567		28,877
Total stock-based compensation expense	$	41,829	$	33,144	$	47,084

Research and development stock-based compensation expense for the year ended December 31, 2025 reflects the expense associated with an ICT equity milestone deemed probable of achievement of $19.7 million. See Note 3, Acquisitions, for additional information regarding ICT equity milestones. At December 31, 2025, total stock-based compensation cost related to unvested awards not yet recognized was $26.6 million, which is expected to be recognized over a remaining weighted-average period of 2.4 years.

Stock Options Repricing

In November 2023, the Board of Directors of the Company approved, effective November 16, 2023, a one-time repricing of certain stock option awards that had been granted to date under the 2021 Plan and 2018 Plan. The repricing impacted stock options with exercise prices greater than $47.40 held by employees who remained employed as-of November 16, 2023 and were not impacted by the Company’s November 16, 2023 reduction in workforce. The original exercise prices of the repriced stock options ranged from $52.20 to $359.00 per share for 200 total grantees with 1,170,843 shares repriced. Each stock option was repriced to have a per share exercise price of $37.40, which was the closing price of the Company’s common stock on November 16, 2023. To receive the new exercise price, option holders were required to be employed with the Company through November 15, 2024. Additionally, the vesting schedule for the unvested shares underlying repriced stock options held by executives at the level of senior vice president and above was extended for an additional year. There were no changes to the vesting schedules for employees below the level of senior vice president. No changes were made to the expiration dates of or number of shares underlying the repriced stock options. Incremental stock-based compensation expense resulting from the repricing was $8.9 million in the aggregate. Expense for vested awards was recognized through November 15, 2024 and expense for unvested awards will be recognized over the remaining service life of the option.

Performance-Based Stock Options

During the year ended December 31, 2025, the Company granted performance-based stock options to certain key employees. Performance-based stock options (“PBOs”) awarded to employees have a three-year performance period and vest based upon the Company’s performance against a two and three-year relative total shareholder return (“rTSR”) metric or upon the achievement of certain clinical development milestones. Certain of the clinical development milestones were probable of achievement as of December 31, 2025, representing 7,062 shares. For the portion of PBOs subject to certain clinical development milestones, 50% vest upon the achievement of the applicable milestone and the remaining 50% vest upon the earlier of (a) one year of service from the date of such achievement and (b) the end of the three-year performance period. The vesting of all PBOs granted is also subject to the respective employee’s continued employment. The Company

valued the portion of the PBOs subject to the rTSR metric using a Monte Carlo simulation. The number of PBOs granted subject to the rTSR metrics represents the target number of options that are eligible to be earned based on the achievement of the metrics established at the beginning of the performance period, which ends on December 31st of the three-year performance period. For the portion of PBOs subject to the rTSR metrics, employees may ultimately earn between zero and 200% of the target number of PBOs granted based on the degree of achievement of the applicable rTSR metric. Accordingly, additional PBOs may be issued or currently outstanding PBOs may be cancelled upon final determination of the degree of achievement of the applicable rTSR metric. PBOs have contractual terms of ten years from grant date.

A summary of the Company’s PBO activity was as follows:


	Number of PBOs	Weighted-Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
PBOs outstanding as of December 31, 2024	—	$	—	—	$	—
Granted(1)	138,250	$	11.07
Exercised	—	$	—
Canceled or forfeited	(39,382)	$	11.07
PBOs outstanding as of December 31, 2025	98,868	$	11.07	9.11	$	1,949
PBOs exercisable as of December 31, 2025	—	$	—	—	$	—

(1) PBO grants reflect the target number of shares eligible to be earned at the time of grant.

Performance-Based Restricted Stock Units

During the year ended December 31, 2024, the Company granted PSU awards to certain key employees. PSUs awarded to employees have a three-year performance period and vest based upon the Company’s performance against a two and three-year rTSR metric, or upon the achievement of certain clinical development milestones. Certain of the clinical development milestones were determined to be probable of achievement as of December 31, 2025, representing 58,238 shares. For the portion of PSUs subject to certain clinical development milestones (other than the bonus clinical development milestone), 50% vest upon the achievement of the applicable milestone, and the remaining 50% vest upon the earlier of (a) one year of service from the date of such achievement and (b) the end of the three-year performance period. The vesting of all PSU awards granted is also subject to the respective employee’s continued employment. The Company valued the portion of PSUs subject to the rTSR metric using a Monte Carlo simulation. The number of PSUs granted subject to the rTSR metrics represents the target number of units that are eligible to be earned based on the achievement of the metrics established at the beginning of the performance period, which ends on December 31st of the three-year performance period. For the portion of PSUs subject to the rTSR metrics, employees may ultimately earn between zero and 200% of the target number of PSUs granted based on the degree of achievement of the applicable rTSR metric. Accordingly, additional PSUs may be issued or currently outstanding PSUs may be cancelled upon final determination of the degree of the achievement of the applicable rTSR metric. Stock-based compensation expense recognized for the PSU awards was $1.7 million and $1.9 million for the years ended December 31, 2025 and 2024, respectively and zero for the year ended December 31, 2023.

A summary of the Company’s PSU activity was as follows:


	Performance-Based Restricted Stock Units Outstanding	Weighted-Average Value at Grant Date Per Share
Unvested PSUs as of December 31, 2024	135,170	$	37.63
PSUs granted(1)	—	$	—
PSUs vested	(33,623)	$	36.00
PSUs forfeited or canceled	(36,029)	$	39.36
Unvested PSUs as of December 31, 2025	65,518	$	37.51

(1) PSU grants reflect the target number of shares eligible to be earned at the time of grant.

The fair value of PSUs vested during the year ended December 31, 2025 was $0.4 million and was zero during both the years ended December 31, 2024 and 2023. As of December 31, 2025, certain of the PSU metrics have been met, resulting in 33,623 shares vesting.

Restricted Stock Units

A summary of the Company’s RSU activity was as follows:


	Restricted Stock Units Outstanding	Weighted-Average Value at Grant Date Per Share
Unvested RSUs as of December 31, 2024	281,190	$	34.40
RSUs granted	287,735	$	11.82
RSUs vested	(139,928)	$	25.66
RSUs forfeited or canceled	(122,582)	$	24.88
Unvested RSUs as of December 31, 2025	306,415	$	19.77

The fair value of RSUs vested during the years ended December 31, 2025, 2024 and 2023 was $1.7 million, $2.0 million and $1.4 million, respectively.

Stock Options

A summary of the Company’s stock option activity was as follows:


	Number of Stock Options	Weighted-Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Options outstanding as of December 31, 2024	2,239,354	$	49.80	6.62	$	1,479
Granted	864,491	$	14.25
Exercised	(3,750)	$	11.07
Canceled or forfeited	(403,651)	$	36.96
Options outstanding as of December 31, 2025	2,696,444	$	40.32	6.14	$	17,090
Options exercisable as of December 31, 2025	1,660,556	$	52.51	4.40	$	4,704


	Year Ended December 31,
	2025		2024		2023
Risk-free interest rate	4.05	%	4.17	%	4.13	%
Expected volatility	85.7	%	75.9	%	88.0	%
Expected term (in years)	6.04		5.89		6.06
Expected dividend yield	0	%	0	%	0	%

The weighted-average grant date fair value of options granted for the years ended December 31, 2025, 2024 and 2023 was $10.31 per share, $26.00 per share and $33.80 per share, respectively. The intrinsic value of options exercised during the years ended December 31, 2025, 2024 and 2023 was $0.1 million, $2.9 million and $6.5 million, respectively.

Segment - Narrative (Details) $ in Millions	12 Months Ended
Segment - Narrative (Details) $ in Millions	Dec. 31, 2025 USD ($) segment	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	1
Reportable segment
Segment Reporting Information [Line Items]
Capital expenditures \| $	$ 0.6	$ 0.6	$ 1.4

Related-Party Transactions (Tables)

12 Months Ended

Dec. 31, 2025

Schedule of Total Income Attributable to Sonoma Sublease

Total operating income from Sonoma and income solely attributable to the Sonoma Sublease are shown in the table below (in thousands). Total operating income includes income attributable to the sublease, as well as additional operating fees recognized in “other operating income, net” such as common area maintenance charges. See Note 11, Leases, for more detail on the Sonoma Sublease.


	Year Ended December 31,
	2025		2024		2023
Sonoma other operating income, net	$	2,740	$	2,838	$	2,592
Sonoma sublease income	$	1,861	$	1,861	$	1,861

Stock-based Compensation - Schedule of Assumptions Used in Black-Scholes Option-Pricing Model for Estimating Fair Value of Stock Options Granted (Details)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Risk-free interest rate (as a percent)	4.05%	4.17%	4.13%
Expected volatility (as a percent)	85.70%	75.90%	88.00%
Expected term (in years)	6 years 14 days	5 years 10 months 20 days	6 years 21 days
Expected dividend yield (as a percent)	0.00%	0.00%	0.00%

Fair Value Measurements - Schedule of SPA Put/Call is Classified as a Level 3 Financial Instrument and the Fair Value Estimated using a Monte Carlo Simulation Valuation Method (Details) - Level 3	Dec. 31, 2025	Jul. 24, 2025
Time to maturity (years)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchase agreement, measurement input	0.67	1.11
Risk-free rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchase agreement, measurement input	0.0355	0.0408
Volatility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchase agreement, measurement input	0.90	0.91

Impairment of Long-Lived Assets	12 Months Ended
Impairment of Long-Lived Assets	Dec. 31, 2025
Property, Plant and Equipment [Abstract]
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets As a result of the successful transition of the manufacturing of ronde-cel from the Company’s West Hills, Los Angeles manufacturing facility to the Company's LyFE Manufacturing CenterTM in Bothell, Washington, and in connection with the planned closure of the West Hills facility, the associated lease has been classified as a separate asset group in 2025. The Company performed an impairment assessment in 2025 and concluded that the carrying value of the West Hills asset group was not recoverable as it exceeded the future undiscounted cash flows the asset was expected to generate from its use and eventual disposition. The Company applied a discounted cash flow method to estimate the fair value of the right‑of-use asset, which represented level 3 nonrecurring fair value measurements. Based on this analysis, the Company recognized long-lived asset impairment charges of $1.4 million for the year ended December 31, 2025 within impairment of long-lived assets in the consolidated statements of operations and comprehensive loss. The Company performed an impairment assessment of long-lived assets for the year ended December 31, 2024 as a result of the sustained decline in the Company’s stock price and related market capitalization, deferral and reprioritization of certain research and development programs and associated reduction in force. The Company operates as a single reporting unit based on its business and reporting structure. The Company determined all of its long-lived assets represent one asset group for the purposes of the long-lived asset impairment assessment. The Company concluded that the carrying value of the asset group was not recoverable as it exceeded the future undiscounted cash flows the assets are expected to generate from their use and eventual disposition over the remaining useful life of the Company’s primary asset; approximately 5 years remain on the initial term of the Company’s operating lease in South San Francisco, California, which expires in March 2031. To allocate and recognize the impairment loss, the Company determined individual fair values of its long-lived assets. The Company applied a discounted cash flow method to estimate the fair values of its leasehold improvements and right-of-use assets. These represented level 3 nonrecurring fair value measurements. The remaining property and equipment, net was determined to not be impaired. Based on this analysis, the Company recognized long‑lived asset impairment charges of $12.6 million on the lease right-of-use assets and $38.7 million on the related leasehold improvements during the year ended December 31, 2024. No impairment was recognized on the remaining long-lived assets as their carrying values were not in excess of their fair values.

Stock-based Compensation - Schedule of RSA and RSU Activity (Details) - Restricted Stock Units (RSUs)	12 Months Ended
	Dec. 31, 2025 $ / shares shares
Number of Shares
Balance at beginning of period (in shares) \| shares	281,190
Granted (in shares) \| shares	287,735
Vested (in shares) \| shares	(139,928)
Forfeited (in shares) \| shares	(122,582)
Balance at end of period (in shares) \| shares	306,415
Weighted-Average Value at Grant Date Per Share
Unvested shares of beginning balance (in dollars per share) \| $ / shares	$ 34.40
Granted (in dollars per share) \| $ / shares	11.82
Vested (in dollars per share) \| $ / shares	25.66
Forfeited (in dollars per share) \| $ / shares	24.88
Unvested shares of ending balance (in dollars per share) \| $ / shares	$ 19.77

Acquisitions (Tables)

12 Months Ended

Dec. 31, 2025

Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]

Schedule of Fair Value of Assets Acquired

The estimated fair value of the assets acquired on November 6, 2025 are as follows (in thousands):


Assets acquired:	As of November 6, 2025
Prepaid clinical supply	$	8,835
LYL273 license	66,332
Total assets	$	75,167

The total consideration paid for the Merger consisted of the following (in thousands):


Fair value of components of purchase price consideration at closing:	As of Closing Date
Cash (including $11.9 million for existing cash balances)	$	41,913
Common Stock	36,011
Representative holdback	200
Contingent consideration payable	11,404
Company’s capitalizable transaction expenses	4,215
Total consideration paid	$	93,743

The estimated fair value of the net assets acquired at Closing Date are as follows (in thousands):


Assets acquired:	As of Closing Date
Cash and cash equivalents	$	14,982
Prepaid expenses and other current assets	1,211
Property and equipment, net	4,446
Long-term deposits	459
Operating lease right-of-use assets	1,816
Assembled workforce intangible asset	1,315
IPR&D asset	87,184
Total assets	$	111,413
Liabilities Assumed:
Accounts payable and other current liabilities	$	16,090
Operating lease liability, long-term	1,580
Total liabilities assumed	17,670
Total net assets acquired	$	93,743

Related-Party Transactions - Schedule of Total Income Attributable to Sonoma Sublease (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Related Party Transaction [Line Items]
Sonoma other operating income, net	$ 2,145	$ 3,309	$ 2,790
Sonoma sublease income	3,601	3,004	2,729
Sonoma \| Related Party
Related Party Transaction [Line Items]
Sonoma other operating income, net	2,740	2,838	2,592
Sonoma sublease income	$ 1,861	$ 1,861	$ 1,861

- Definition

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

+ References

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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Paragraph 1
-Subparagraph (SX 210.4-08(k)(2))
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-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: 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)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

+ Details

Acquisitions

12 Months Ended

Dec. 31, 2025

Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]

Acquisitions

ICT License Acquisition

On November 6, 2025, the Company entered into an Exclusive License Agreement with Innovative Cellular Therapeutics Holdings Limited and Innovative Cellular Therapeutics, Inc. (together, “ICT”) for the development and commercialization of LYL273, a novel GCC-targeted CAR T-cell product candidate for the treatment of mCRC and other GCC-expressing cancers (the “ICT License Agreement”). Pursuant to the terms of the ICT License Agreement, the Company received exclusive global rights, outside of mainland China, Hong Kong, Macau and Taiwan, to research, develop, manufacture, commercialize and otherwise exploit LYL273 (“LYL273 license”), along with clinical supply through the technology transfer period (subject to a $10 million cap) (“Prepaid clinical supply”), in exchange for an upfront payment of $40 million in cash and the issuance of 1.9 million shares of the Company’s common stock. The fair value of the common stock consideration transferred for the ICT License Agreement was calculated based on the closing stock price of the Company’s common stock on November 6, 2025, which was $17.88 per share, resulting in total upfront consideration of approximately $75.2 million. In addition, ICT is eligible to receive additional cash and equity payments of (i) a potential $30 million clinical milestone payment, up to $115 million upon the achievement of certain late-stage regulatory milestones and up to $675 million in commercial sales milestones; (ii) up to an additional 1.85 million shares of the Company’s common stock based on the achievement of certain clinical and regulatory milestones; and (iii) tiered royalties ranging from mid-single-digits up to 10% on annual net sales in the United States and low to mid-single-digit royalties on annual net sales in other countries within the licensed territory.

The estimated fair value of the assets acquired on November 6, 2025 are as follows (in thousands):


Assets acquired:	As of November 6, 2025
Prepaid clinical supply	$	8,835
LYL273 license	66,332
Total assets	$	75,167

The fair value of the Prepaid clinical supply was estimated using a market approach as the fair value a market participant would require for the materials (Level 3 of the fair value hierarchy), which resulted in a fair value that differs from the $10 million contractual limit. The Company utilized estimates and assumptions in determining the number of patients and the fair value of Prepaid clinical supply per patient during the technology transfer period to estimate the fair value of the Prepaid clinical supply using the market approach. A small change in the number of patients or the estimate of the fair value of Prepaid clinical supply per patient may have a material change in the total estimated fair value of the

Prepaid clinical supply. During the year ended December 31, 2025, the Company received $1.3 million in prepaid clinical supply, resulting in a remaining prepaid clinical supply balance of $7.5 million as of December 31, 2025. Prepaid clinical supply balances are recorded in prepaid expenses and other current assets in the Company’s consolidated balance sheets.

The Company determined that the cash milestones and royalty payments are not subject to derivative accounting under ASC 815, Derivatives and Hedging, as their settlement is contingent upon future net sales and operational milestones related to LYL273. The Company did not record an associated liability on the acquisition date for the cash milestones or royalty payments as the milestones had not yet been achieved. The Company will recognize any future cash milestones or royalty payments in the period in which the cash milestones or royalty payments become due and payable. The Company has not made or accrued for cash milestones or royalty payments as these have not become due and payable.

The Company determined that the milestone payments payable in the Company’s common stock are subject to accounting under ASC 718, Compensation - Stock Compensation. Consistent with the Company’s treatment of other performance-based equity awards, compensation expense is recognized for the number of shares expected to be earned after assessing the probability that a certain performance condition will be met and the targeted payout level associated with the performance condition expected to be achieved. At each reporting date, the Company is required to evaluate whether achievement of a performance condition is probable. If performance conditions are not met or not expected to be met, any compensation expense previously recognized associated with the awards will be reversed. As of December 31, 2025, it was determined a clinical milestone of 1.1 million shares of common stock was probable of achievement resulting in stock compensation expense of $19.7 million, which was recognized in research and development expense.

The Company concluded that the arrangement met the definition of an asset acquisition rather than a business combination, as the transaction failed to meet the definition of a business under ASC 805, Business Combinations. The $66.3 million fair value of the LYL273 license IPR&D acquired was charged to acquired IPR&D expense during the year ended December 31, 2025 as it had no alternative future use as of November 6, 2025.

ImmPACT Acquisition

On October 31, 2024 (the “Closing Date”), the Company completed its previously announced acquisition of ImmPACT Bio USA Inc., a Delaware corporation (“ImmPACT”), pursuant to the Agreement and Plan of Merger (the “Merger Agreement”), dated as of October 24, 2024, by and among the Company, ImmPACT, Inspire Merger Sub Inc., a Delaware corporation and an indirect, wholly owned subsidiary of the Company (“Merger Sub”), and an attorney-in-fact of ImmPACT securityholders (the “Representative”).

Pursuant to the terms of the Merger Agreement, on the Closing Date, the Company acquired all of the outstanding equity interests of ImmPACT in exchange for an upfront payment of $30.0 million in cash (in addition to approximately $11.9 million for ImmPACT’s existing cash balance, net of certain of ImmPACT’s unpaid transaction expenses) and 1.875 million shares of Company common stock. The acquisition was effected via a merger whereby Merger Sub merged with and into ImmPACT (the “Merger”), with ImmPACT surviving the merger as an indirect, wholly-owned subsidiary of the Company. Contingent consideration following the Closing Date includes (a) additional equity consideration of 625,000 shares of Company Common Stock (“contingent consideration payable”) that may be earned upon the achievement of the earlier to occur of (i) the demonstration of certain clinical milestones or (ii) the receipt of certain regulatory approvals and (b) a low single-digit royalty on future net sales of the dual-targeting CD19/20 CAR T‑cell product in the United States. Contingent consideration payable in the Company’s consolidated balance sheet as of December 31, 2024 consisted of the additional equity consideration of 625,000 shares of Company common stock. All per-share values have been retroactively adjusted to reflect the Reverse Split effected on May 30, 2025. See Note 2, Summary of Significant Accounting Policies, for additional information regarding the Reverse Split.

The total consideration paid for the Merger consisted of the following (in thousands):


Fair value of components of purchase price consideration at closing:	As of Closing Date
Cash (including $11.9 million for existing cash balances)	$	41,913
Common Stock	36,011
Representative holdback	200
Contingent consideration payable	11,404
Company’s capitalizable transaction expenses	4,215
Total consideration paid	$	93,743

The fair value of the common stock consideration transferred for the acquisition of ImmPACT was calculated based on the closing stock price of the Company’s common stock on October 31, 2024, which was $19.21 per share. The fair value of the contingent consideration payable was derived based on certain valuation inputs, including the closing share price of Lyell common stock on October 31, 2024 and the probability of meeting the milestone, as further discussed in Note 8, Fair Value Measurements. Pursuant to the terms of the Merger Agreement, the Company has a right to offset and cause the sellers to forfeit shares underlying the contingent consideration payable against certain indemnification claims and indemnifiable losses. As a result of this provision, the number of shares underlying the contingent consideration payable is contingently subject to adjustments and the Company has concluded that the arrangement is not indexed to the Company’s equity pursuant to guidance in Accounting Standards Codification (“ASC”) 815-40. Accordingly, the contingent consideration payable was classified as a liability and remeasured at fair value at each reporting date with changes in fair value reported in earnings until the liability was settled in accordance with the terms of the Merger Agreement.

The Company determined that the contingent consideration for the royalty payments is not subject to derivative accounting under ASC 815, Derivatives and Hedging, as its settlement is contingent upon future net sales of the Company's dual-targeting CD19/20 CAR T-cell product in the United States. Therefore, the Company did not record an associated contingent consideration liability on the acquisition date for the royalty payments. The Company will recognize any future contingent consideration payments in the period in which the royalty payments become due and payable. The Company has not made or accrued for contingent payments relating to the royalty payments as these have not become due and payable.

The estimated fair value of the net assets acquired at Closing Date are as follows (in thousands):


Assets acquired:	As of Closing Date
Cash and cash equivalents	$	14,982
Prepaid expenses and other current assets	1,211
Property and equipment, net	4,446
Long-term deposits	459
Operating lease right-of-use assets	1,816
Assembled workforce intangible asset	1,315
IPR&D asset	87,184
Total assets	$	111,413
Liabilities Assumed:
Accounts payable and other current liabilities	$	16,090
Operating lease liability, long-term	1,580
Total liabilities assumed	17,670
Total net assets acquired	$	93,743

The Company concluded that the arrangement met the definition of an asset acquisition rather than a business combination, as substantially all of the fair value of the gross assets acquired was concentrated in a single identifiable asset,

IPR&D of product candidate ronde-cel. The $87.2 million fair value of the IPR&D acquired was charged to acquired IPR&D expense during the year ended December 31, 2024 as it had no alternative future use at the time of the Closing Date.

Consolidated Statements of Operations and Comprehensive Loss (Parenthetical)	May 30, 2025
Statement of Comprehensive Income [Abstract]
Reverse stock split	0.05

Consolidated Balance Sheets (Parenthetical)	Dec. 31, 2025 $ / shares shares	Dec. 31, 2024 $ / shares shares
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share) \| $ / shares	$ 0.0001	$ 0.0001
Preferred stock authorized (in shares)	10,000,000	10,000,000
Preferred stock issued (in shares)	0	0
Preferred stock outstanding (in shares)	0	0
Common stock, par value (in dollars per share) \| $ / shares	$ 0.0001	$ 0.0001
Common stock authorized (in shares)	500,000,000	500,000,000
Common stock issued (in shares)	21,251,000	14,744,000
Common stock outstanding (in shares)	21,251,353	14,743,777

Basis of Presentation and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2025
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All significant intercompany transactions and balances have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform with the current period presentation.
Consolidations	All significant intercompany transactions and balances have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform with the current period presentation.
Use of Estimates	Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with GAAP requires management to make judgments, estimates and assumptions that affect reported amounts and related disclosures. Specific accounts that require management estimates include, but are not limited to, stock-based compensation, valuation of long‑lived and acquired assets, the SPA put/call (as defined below) liability, other investments and accrued expenses. See Note 13, Stockholders’ Equity, for additional information regarding the SPA put/call. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results could differ materially from those estimates.
Comprehensive Loss	Comprehensive Loss Comprehensive loss includes net loss and certain changes in stockholders’ equity that are excluded from net loss. For the years ended December 31, 2025, 2024 and 2023, this was comprised of net unrealized gains and losses on the Company’s marketable securities.
Cash and Cash Equivalents	The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents consist primarily of amounts invested in investment grade fixed income securities and money market accounts.
Restricted Cash	Restricted cash is cash held in a bank account and is used as collateral associated with the Company’s corporate credit card program as well as collateral for a letter of credit in favor of one of the Company’s landlords.
Marketable Securities	Marketable Securities The Company generally invests its excess cash in investment grade short- to intermediate-term fixed income securities. Such investments are classified as available-for-sale and are carried at fair value, with the unrealized gains and losses reported as a component of comprehensive loss. Realized gains and losses on available-for-sale securities are included in other (expense) income, net. The cost of investments sold is based on the specific-identification method. The Company classifies those investments that are not required for use in current operations and that mature in more than 12 months as non-current marketable securities in the accompanying consolidated balance sheets. Each reporting period, the Company evaluates whether declines in fair value below carrying value are due to expected credit losses, as well as the Company’s ability and intent to hold the investment until a forecasted recovery occurs. Expected credit losses, if any, are recorded as an allowance through other (expense) income, net.
Valuation of Other Investments	Valuation of Other Investments The Company accounts for its strategic equity interests in common stock and in-substance common stock in non‑publicly traded companies for which it does not have the ability to exercise significant influence in accordance with Accounting Standards Codification (“ASC”) 321, Investments – Equity Securities (“ASC 321”). Upon acquisition, these investments are measured at cost, which represents the then fair value. Under ASC 321, the Company can elect to subsequently measure the investments at initial cost, minus impairment and any changes, plus or minus, resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer (“measurement alternative”). This election must be made for each investment separately. The Company has made this election for all investments in this category and will continue to measure these investments using this method until they no longer qualify to be measured in accordance with this method. Changes in the carrying value of other investments are recognized through net loss. Each reporting period, the Company performs a qualitative assessment to evaluate whether the investment is impaired. The Company’s assessment includes a review of recent operating results and trends, recent sales/acquisitions of the investee securities and other factors that raise concerns about the investee’s ability to continue as a going concern. If the investment is impaired, an impairment charge is recognized in the amount by which the carrying amount of the investment exceeds the estimated fair value of the investment, with the impairment charge recognized through net loss. See Note 7, Other Investments, for details related to investment impairments recognized during the years ended December 31, 2025, 2024 and 2023.
Property and Equipment, Net	Property and Equipment, Net Property and equipment primarily consist of laboratory equipment, computer equipment and software, furniture and fixtures and leasehold improvements. Property and equipment are stated at cost less accumulated depreciation and amortization and, if applicable, impairment charges. Depreciation is calculated using the straight-line method based on the estimated useful lives of the related assets, which are generally three to five years. For leasehold improvements, amortization is calculated using the straight‑line method based on the shorter of the useful life or the lease term. When assets are retired or otherwise disposed of, the cost and related accumulated depreciation and amortization are removed from the balance sheet and the resulting gain or loss is recorded in other operating income, net in the period realized. Maintenance and repairs are expensed as incurred. The Company reviews its property and equipment for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable.
Valuation of Long-lived Assets	Valuation of Long-lived Assets Long-lived assets are reviewed each reporting period for impairment or whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable, which may warrant adjustments to carrying values or estimated useful lives. Recoverability is measured by comparison of the carrying amount of an asset group to the future net undiscounted cash flows that the assets are expected to generate. If the carrying amount of an asset group exceeds its estimated future cash flows, an impairment charge is recognized in the amount by which the carrying amount of the asset group exceeds the fair value of the asset group. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the projected discounted future net cash flows arising from the asset group.
Leases	Leases The Company leases certain office, laboratory and manufacturing spaces. In addition to minimum rent, the leases require payment of real estate taxes, insurance, common area maintenance charges and other executory costs. At inception of a contract, the Company determines whether an arrangement is or contains a lease based on the unique facts and circumstances present in the arrangement. For all leases, the Company determines the classification of the lease as either operating or financing. As of December 31, 2025 and 2024, all of the Company’s leases were classified as operating leases. The Company recognizes right-of-use (“ROU”) assets and lease liabilities at the lease commencement date based on the present value of future lease payments over the lease term. As the Company’s leases do not provide an implicit rate, an incremental borrowing rate at each lease commencement date is used to determine the present value of future lease payments. The incremental borrowing rate is the rate of interest that the Company would pay to borrow equivalent funds on a collateralized basis at the lease commencement date. To estimate the incremental borrowing rate, a credit rating applicable to the Company is estimated using a synthetic credit rating analysis since the Company does not currently have a rating agency-based credit rating. The ROU asset includes any lease payments made prior to the lease commencement date and is reduced by any lease incentives received or deemed payable to the Company. The lease term may include options to extend or terminate the lease when it is reasonably certain that a lease option will be exercised. Lease expense is recognized on a straight-line basis over the lease term within operating expenses on the consolidated statements of operations and comprehensive loss. The Company has elected the practical expedient to not separate lease and non-lease components for real estate leases. Additionally, the Company has elected the short-term lease recognition exemption for all short-term leases and as a result, lease liabilities and ROU assets are not included on the consolidated balance sheets for leases with an initial term of 12 months or less. The Company evaluates lease arrangements for impairment whenever events or changes in circumstances indicate that the carrying amounts of the right-of-use asset may not be fully recoverable. To the extent an impairment of the right-of-use asset is identified, the Company recognizes a lease impairment and subsequently amortizes the remaining lease asset on a straight-line basis (unless another systematic basis is more representative of the pattern in which the Company expects to consume the future economic benefits from the asset) from the date of impairment to the earlier of the right‑of‑use asset’s useful life or the end of the lease term.
Fair Value Measurements	Fair Value Measurements The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. The fair value hierarchy prioritizes valuation inputs based on the observable nature of those inputs. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The hierarchy defines three levels of valuation inputs: Level 1 – Quoted prices in active markets for identical assets or liabilities. Level 2 – Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 3 – Unobservable inputs that reflect the Company’s own assumptions about the assumptions market participants would use in pricing the asset or liability. The Company’s financial instruments, in addition to those presented in Note 8, Fair Value Measurements, include cash, restricted cash, other investments, accounts payable and accrued liabilities and other current liabilities. The carrying amount of cash, restricted cash, accounts payable and accrued liabilities and other current liabilities approximate fair value because of the short-term nature of these instruments. As described in Note 7, Other Investments, other investments are carried at cost, minus impairment and any changes, plus or minus, resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer.
Research and Development Expense	Research and Development Expense The Company records expense for research and development costs as incurred. Research and development expenses consist of costs incurred by the Company for the discovery and development of its technology platforms and product candidates and includes costs incurred in connection with strategic collaborations, costs to license technology, personnel-related costs, including stock-based compensation expense, facility and technology related costs, research and laboratory expenses, as well as other expenses, which include consulting fees and other costs. Upfront payments and milestones paid to third parties in connection with technology platforms that have not reached technological feasibility and do not have an alternative future use are expensed as incurred. Clinical expenses are a component of research and development expense. The Company accrues and expenses clinical trial services performed by third parties based upon actual work completed in accordance with agreements established with its service providers. The Company estimates the costs through discussions with internal personnel and external service providers as to the progress or stage of completion of services and the agreed-upon fees to be paid for such services.
General and Administrative Expense	General and Administrative Expense General and administrative costs are expensed as incurred and include personnel-related expenses, including stock-based compensation expense for personnel in executive, legal, finance and other administrative functions, legal costs, transaction costs related to collaboration and licensing agreements, as well as fees paid for accounting and tax services, consulting fees and facilities costs not otherwise included in research and development expenses. Legal costs include those related to corporate, dispute and patent matters.
Concentrations of Credit Risk	Concentrations of Credit Risk and Off-balance Sheet Risk The Company maintains its cash, cash equivalents and restricted cash with high quality, accredited financial institutions. Restricted cash is cash held in a bank account and is used as collateral associated with the Company’s corporate credit card program as well as collateral for a letter of credit in favor of one of the Company’s landlords. Cash, cash equivalents and restricted cash amounts, at times, may exceed federally insured limits. The Company also makes short-term investments in money market funds, U.S. Treasury securities, U.S. government agency securities and corporate debt securities, which can be subject to certain credit risk. However, the Company mitigates the risks by investing in high‑grade instruments, limiting exposure to any one issuer or type of investment and monitoring the ongoing creditworthiness of the financial institutions and issuers. The Company has not experienced any credit losses in such accounts and does not believe it is exposed to significant risk on these funds.
Off-balance Sheet Risk	The Company has no off‑balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements.
Claims and Contingencies	Claims and Contingencies From time to time, the Company may become involved in litigation and proceedings relating to claims arising from the ordinary course of business. The Company accrues a liability if the likelihood of an adverse outcome is probable and the amount is estimable. If the likelihood of an adverse outcome is only reasonably possible (as opposed to probable), or if an estimate is not determinable, the Company provides disclosure of a material claim or contingency.
Stock-based Compensation	Stock-based Compensation Under ASC 718, the Company measures and recognizes expense for restricted stock units (“RSUs”), performance-based restricted stock units (“PSUs”), employee stock purchases related to the Employee Stock Purchase Plan, stock options, performance awards and contingent milestone payments granted to employees, directors, consultants or other third parties based on the fair value of the awards on the date of grant. Stock-based compensation expense for RSAs, RSUs, stock options and contingent milestone payments are recognized on a straight-line basis over the requisite service period, which is generally the vesting period of the respective award. The Company accounts for forfeitures as they occur. For RSAs, RSUs, certain PSUs and contingent milestone payments, the fair value of the Company’s common stock is used to determine the resulting stock-based compensation expense. The fair value of certain stock options is estimated on the date of grant using a Black-Scholes option pricing model, which requires management to apply judgment and make estimates using inputs including: •Fair Value of Common Stock—The fair value of common stock is based on the closing price as reported on the Nasdaq Global Select Market on the date of grant. •Expected Term—The expected term represents the period that a stock-based award is expected to be outstanding. The Company generally uses the simplified method to determine the expected term, which is based on the average of the time-to-vesting and the contractual life of the option. The Company generally uses the simplified method as provided for under the applicable guidance for entities with a limited history of relevant stock option exercise activity. •Expected Volatility—The expected volatility of stock options is determined by weighting the historical volatility of the Company’s common stock with the historical volatilities of the stock of similar entities within the Company’s industry over a period commensurate with the Company’s expected term assumption. •Risk-Free Interest Rate—The risk-free interest rate is based on the interest rate payable on U.S. Treasury securities in effect at the time of grant for a period that is commensurate with the Company’s expected term assumption. •Expected Dividend—The Company has not historically paid, and does not expect for the foreseeable future to pay a dividend. Therefore, the Company used an expected dividend yield of zero. For awards with performance conditions that vest upon a performance condition being met, compensation expense is recognized for the number of shares expected to be earned after assessing the probability that a certain performance condition will be met and the targeted payout level associated with the performance condition expected to be achieved. At each reporting date, the Company is required to evaluate whether achievement of a performance condition or a contingent milestone payment is probable. Cumulative adjustments are recorded each quarter to reflect the estimated outcome of the performance-related conditions until the date results are determined and settled. If performance conditions are not met or not expected to be met, any compensation expense previously recognized associated with the awards will be reversed. The fair values of the Company’s PSUs and performance-based stock options that have market-based metrics are estimated using Monte Carlo simulations. The Company applies an accelerated attribution method to recognize stock-based compensation expense over the applicable service period for these awards. The number of shares expected to be earned is considered in the grant date valuation; therefore, the expense is not subsequently adjusted to reflect the actual shares ultimately earned.
Income Taxes	Income Taxes The Company determines its deferred tax assets and liabilities based on the differences between the financial reporting and tax basis of assets and liabilities. The deferred tax assets and liabilities are measured using the enacted tax rates that will be in effect when the differences are expected to reverse. A valuation allowance is recorded when it is more likely than not that the deferred tax asset will not be recovered. The Company applies judgment in the determination of the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The Company recognizes any material interest and penalties related to unrecognized tax benefits in income tax expense.
Segments	Segments Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business in one operating segment and one reportable segment.
Acquisitions and Contingent Consideration	Acquisitions The Company evaluates acquisitions of assets and other similar transactions to assess whether or not the transaction should be accounted for as a business combination or asset acquisition by first applying a screen to determine if substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or group of similar identifiable assets. If the screen is met, the transaction is accounted for as an asset acquisition. If the screen is not met, further determination is required as to whether or not the Company has acquired inputs and processes that have the ability to create outputs which would meet the requirements of a business in which case the transaction is accounted for using the acquisition method of accounting, which requires, among other things, that assets acquired and liabilities assumed be recognized at their estimated fair values as of the acquisition date, and that the fair value of acquired intangibles be recorded on the balance sheet. Any excess of the purchase price over the assigned fair values of the net assets acquired is recorded as goodwill in a business combination. If the Company determines an acquisition does not meet the definition of a business combination under the acquisition method of accounting, the transaction is accounted for as an asset acquisition. Direct transaction costs are recognized as part of the cost of an asset acquisition. The cost of an asset acquisition, including transaction costs, is allocated to identifiable assets acquired and liabilities assumed based on a relative fair value basis. Goodwill is not recognized in an asset acquisition. In an asset acquisition, upfront payments allocated to in-process research and development (“IPR&D”) are recorded in acquired in‑process research and development expense if it is determined that there is no alternative future use, and subsequent milestone payments are recorded in research and development expense when achieved for technology that has not yet met product feasibility. Contingent Consideration Contingent consideration relates to the potential payments for achieving certain clinical and/or regulatory milestones. For transactions accounted for as asset acquisitions, the Company records contingent consideration at fair value at the date of the acquisition when deemed probable. Liabilities for contingent consideration are remeasured each reporting period and subsequent changes in fair value are recognized within other (expense) income, net in the consolidated statements of operations and comprehensive loss. The assumptions utilized in the calculation of the fair values include the probability of success and the Company’s stock price. Contingent consideration involves certain assumptions requiring significant judgment and actual results may differ from estimated amounts.
Recently Adopted Accounting Pronouncements and Recently Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements Derivatives In September 2025, the FASB issued Accounting Standards Update (“ASU”) 2025-07, Derivatives and Hedging (Topic 815) and Revenue from Contracts with Customers (Topic 606). The guidance refines the scope of Topic 815 to clarify which contracts are subject to derivative accounting. The amendments in ASU 2025-07 are effective for fiscal years and interim periods beginning after December 15, 2026, with early adoption permitted. The Company early adopted ASU 2025-07 for fiscal 2025 on a prospective basis and the adoption of this standard did not have a significant impact on the Company’s consolidated financial statements. Income Taxes In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The amendments are effective for annual periods beginning after December 15, 2024 and may be applied either prospectively or retrospectively. The Company adopted ASU 2023-09 for the fiscal 2025 year prospectively with no significant updates. Recently Issued Accounting Pronouncements Income Statement Expense Disaggregation In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures, to require more detailed information about specified categories of expenses (purchases of inventory, employee compensation, depreciation and amortization) included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The amendments may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of this ASU or (2) retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on its consolidated financial statements. Interim Reporting In December 2025, the FASB issued ASU 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements, which clarifies the guidance in Topic 270 to improve the consistency of interim financial reporting. The ASU provides a comprehensive list of required interim disclosures and introduces a disclosure principle requiring entities to disclose events since the end of the last annual reporting period that have a material impact on the entity. ASU 2025-11 is effective for fiscal years beginning after December 15, 2027, including interim periods within those fiscal years, with early adoption permitted. The Company is currently evaluating the impact of ASU 2025-11 on its consolidated financial statements.

Income Taxes - Schedule of Changes in Company’s Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Deferred Tax Assets, Valuation Allowance [Roll Forward]
Beginning balance	$ 359,440	$ 248,420
Change charged to income tax expense	69,507	111,020
Ending balance	$ 428,947	$ 359,440

Cash Equivalents and Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2025

Cash and Cash Equivalents [Abstract]

Schedule of Fair Value and Amortized Cost of Cash Equivalents

The fair value and amortized cost of cash equivalents and fixed income marketable securities by major security type are as follows (in thousands):


	December 31, 2025
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	$	49,766	$	—	$	—	$	49,766
U.S. Treasury securities	175,839		233		—		176,072
U.S. government agency securities	6,528		5		—		6,533
Corporate debt securities	4,430		4		—		4,434
Total cash equivalents and fixed income marketable securities	$	236,563	$	242	$	—	$	236,805


Classified as:	Fair Value
Cash equivalents	$	49,766
Marketable securities	187,039
Marketable securities, non-current	—
Total cash equivalents and fixed income marketable securities	$	236,805


	December 31, 2024
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	$	73,975	$	—	$	—	$	73,975
U.S. Treasury securities	226,049		262		(40)		226,271
U.S. government agency securities	36,765		51		(1)		36,815
Corporate debt securities	21,473		20		(1)		21,492
Total cash equivalents and fixed income marketable securities	$	358,262	$	333	$	(42)	$	358,553


Classified as:	Fair Value
Cash equivalents	$	80,639
Marketable securities	264,900
Marketable securities, non-current	13,014
Total cash equivalents and fixed income marketable securities	$	358,553

Schedule of Fair Value and Amortized Cost of Marketable Securities

The fair value and amortized cost of cash equivalents and fixed income marketable securities by major security type are as follows (in thousands):


	December 31, 2025
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	$	49,766	$	—	$	—	$	49,766
U.S. Treasury securities	175,839		233		—		176,072
U.S. government agency securities	6,528		5		—		6,533
Corporate debt securities	4,430		4		—		4,434
Total cash equivalents and fixed income marketable securities	$	236,563	$	242	$	—	$	236,805


Classified as:	Fair Value
Cash equivalents	$	49,766
Marketable securities	187,039
Marketable securities, non-current	—
Total cash equivalents and fixed income marketable securities	$	236,805


	December 31, 2024
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	$	73,975	$	—	$	—	$	73,975
U.S. Treasury securities	226,049		262		(40)		226,271
U.S. government agency securities	36,765		51		(1)		36,815
Corporate debt securities	21,473		20		(1)		21,492
Total cash equivalents and fixed income marketable securities	$	358,262	$	333	$	(42)	$	358,553


Classified as:	Fair Value
Cash equivalents	$	80,639
Marketable securities	264,900
Marketable securities, non-current	13,014
Total cash equivalents and fixed income marketable securities	$	358,553

- 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
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
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Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
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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

Segment (Tables)

12 Months Ended

Dec. 31, 2025

Segment Reporting [Abstract]

Schedule of Reporting Segment

The measure of segment assets is reported on the consolidated balance sheets as total assets.


	Year Ended December 31,
	2025		2024		2023
Revenue	$	36	$	61	$	130
Less:
Technical operations	47,202		46,102		49,851
Clinical development	36,671		38,561		27,241
Support functions	25,737		29,870		34,096
Lease costs	16,643		16,885		14,788
Operations management	13,106		14,145		22,814
Research activities	11,038		25,284		33,309
Other segment items(1)	124,087		172,208		52,663
Net loss	$	274,448	$	342,994	$	234,632

Consolidated Balance Sheets - USD ($)
$ in Thousands

Dec. 31, 2025

Dec. 31, 2024

Current assets:

Cash and cash equivalents

$ 60,181

$ 105,597

Marketable securities

187,039

264,930

Prepaid expenses and other current assets

13,719

9,067

Total current assets

260,939

379,594

Restricted cash

1,585

1,690

Marketable securities, non-current

13,014

Other investments

19,000

Property and equipment, net

34,771

48,200

Operating lease right-of-use assets

18,871

24,739

Other non-current assets

4,886

4,622

Total assets

340,052

490,859

Current liabilities:

Accounts payable

2,893

5,366

Accrued liabilities and other current liabilities

46,519

40,822

Contingent consideration payable

7,600

Total current liabilities

49,412

53,788

Operating lease liabilities, non-current

41,921

50,994

Other non-current liabilities

517

3,253

Total liabilities

91,850

108,035

Commitments and contingencies (Note 18)

Stockholders’ equity:

Preferred stock, $0.0001 par value; 10,000 shares authorized at December 31, 2025 and 2024, respectively; no shares issued and outstanding at December 31, 2025 and 2024

Common stock, $0.0001 par value; 500,000 shares authorized at December 31, 2025 and 2024, respectively; 21,251 and 14,744 shares issued and outstanding at December 31, 2025 and 2024, respectively

^[1]

Additional paid-in capital

^[1]

1,867,512

1,727,638

Accumulated other comprehensive income

242

291

Accumulated deficit

(1,619,554)

(1,345,106)

Total stockholders’ equity

248,202

382,824

^[2]

Total liabilities and stockholders’ equity

$ 340,052

$ 490,859

[1]	1. Amounts previously reported have been retroactively adjusted to reflect the 1-for-20 reverse stock split effected on May 30, 2025. See Note 2.
[2]	1. Amounts previously reported have been retroactively adjusted to reflect the 1-for-20 reverse stock split effected on May 30, 2025. See Note 2

Income Taxes - Schedule of Reconciliation of Federal Statutory Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
U.S. federal statutory tax	21.00%	21.00%	21.00%
State tax, net of federal benefit		4.61%	7.45%
Change in valuation allowance	(19.60%)	(20.39%)	(29.10%)
Stock-based compensation	(2.12%)	(2.17%)	(2.25%)
Tax credits	1.30%	2.23%	2.96%
IPR&D		(0.0534)	0
Other	0.01%	0.06%	(0.06%)
Effective income tax rate	0.00%	0.00%	0.00%

Cover - USD ($) $ in Millions	12 Months Ended
Cover - USD ($) $ in Millions	Dec. 31, 2025	Mar. 09, 2026	Jun. 30, 2025
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-40502
Entity Registrant Name	Lyell Immunopharma, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	83-1300510
Entity Address, Address Line One	201 Haskins Way
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	650
Local Phone Number	695-0677
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	LYEL
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction Flag	false
Entity Shell Company	false
Entity Public Float			$ 129
Entity Common Stock, Shares Outstanding		23,307,143
Documents Incorporated by Reference	Portions of the registrant’s Proxy Statement for the 2026 Annual Meeting of Stockholders are incorporated herein by reference in Part III of this Annual Report on Form 10-K to the extent stated herein. Such proxy statement will be filed with the Securities and Exchange Commission within 120 days of the registrant’s fiscal year ended December 31, 2025.
Entity Central Index Key	0001806952
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Amendment Flag	false

Convertible Preferred Stock	12 Months Ended
Convertible Preferred Stock	Dec. 31, 2025
Equity [Abstract]
Convertible Preferred Stock	Convertible Preferred Stock As of December 31, 2025, no shares of convertible preferred stock were outstanding.

Cash Equivalents and Marketable Securities - Schedule of Fair Value and Amortized Cost of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Marketable Securities [Line Items]
Amortized Cost	$ 236,563	$ 358,262
Gross Unrealized Gains	242	333
Gross Unrealized Losses	0	(42)
Classified as:
Fair Value	236,805	358,553
Cash equivalents
Classified as:
Fair Value	49,766	80,639
Marketable securities
Classified as:
Fair Value	187,039	264,900
Marketable securities, non-current
Classified as:
Fair Value	0	13,014
Money market funds
Marketable Securities [Line Items]
Amortized Cost	49,766	73,975
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Classified as:
Fair Value	49,766	73,975
U.S. Treasury securities
Marketable Securities [Line Items]
Amortized Cost	175,839	226,049
Gross Unrealized Gains	233	262
Gross Unrealized Losses	0	(40)
Classified as:
Fair Value	176,072	226,271
U.S. government agency securities
Marketable Securities [Line Items]
Amortized Cost	6,528	36,765
Gross Unrealized Gains	5	51
Gross Unrealized Losses	0	(1)
Classified as:
Fair Value	6,533	36,815
Corporate debt securities
Marketable Securities [Line Items]
Amortized Cost	4,430	21,473
Gross Unrealized Gains	4	20
Gross Unrealized Losses	0	(1)
Classified as:
Fair Value	$ 4,434	$ 21,492

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2025
Audit Information [Abstract]
Auditor Name	Ernst & Young LLP
Auditor Location	San Mateo, California
Auditor Firm ID	42

Stock-based Compensation - Schedule of Performance Shares Units (Details) - Performance Shares	12 Months Ended
	Dec. 31, 2025 $ / shares shares
Performance-Based Restricted Stock Units Outstanding
Balance at beginning of period (in shares) \| shares	135,170
PSUs granted (in shares) \| shares	0
PSUs vested (in shares) \| shares	(33,623)
PSUs forfeited or canceled (in shares) \| shares	(36,029)
Balance at end of period (in shares) \| shares	65,518
Weighted-Average Value at Grant Date Per Share
Unvested shares of beginning balance (in dollars per share) \| $ / shares	$ 37.63
Granted (in dollars per share) \| $ / shares	0
Vested (in dollars per share) \| $ / shares	36.00
Forfeited (in dollars per share) \| $ / shares	39.36
Unvested shares of ending balance (in dollars per share) \| $ / shares	$ 37.51

Accrued Liabilities and Other Current Liabilities

12 Months Ended

Dec. 31, 2025

Accrued Liabilities and Other Liabilities [Abstract]

Accrued Liabilities and Other Current Liabilities

Accrued liabilities and other current liabilities consisted of the following (in thousands):


	December 31,
	2025		2024
SPA put/call	$	11,411	$	—
Accrued compensation and related benefits	11,154		19,235
Accrued research and development expenses	9,117		9,439
Current lease liabilities	9,073		7,974
Other	2,559		2,999
Deferred lease income	2,535		483
Accrued legal	670		692

Total accrued liabilities and other current liabilities	$	46,519	$	40,822

Impairment of Long-Lived Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Remaining lease term (in years)	5 years
Impairment of long-lived assets	$ 1,443	$ 51,297	$ 0
Right Of Use Asset
Property, Plant and Equipment [Line Items]
Impairment of long-lived assets		12,600	0
Leasehold improvements
Property, Plant and Equipment [Line Items]
Impairment of long-lived assets	$ 0	$ 38,700	$ 0

Consolidated Statements of Stockholders’ Equity (Parenthetical)	May 30, 2025
Statement of Stockholders' Equity [Abstract]
Reverse stock split	0.05

Organization	12 Months Ended
Organization	Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	OrganizationLyell Immunopharma, Inc. (the “Company”) was incorporated in Delaware in June 2018. The Company is a late‑stage clinical cell therapy company advancing a pipeline of proprietary next-generation autologous chimeric antigen receptor (“CAR”) T-cell product candidates for patients with hematologic malignancies and solid tumors. The Company’s lead product candidate, rondecabtagene autoleucel (“ronde-cel”, also known as LYL314), is an autologous dual‑targeting CD19/CD20 CAR T‑cell therapy in development for large B-cell lymphoma (“LBCL”). The Company has recently acquired exclusive global rights outside of mainland China, Hong Kong, Macau and Taiwan, to a novel guanylyl cyclase C (“GCC”)-targeted CAR T-cell product candidate in early clinical development for refractory metastatic colorectal cancer (“mCRC”) and other GCC-expressing cancers. The Company’s primary activities since incorporation have been to develop investigational T‑cell therapies, conduct research and development, execute clinical trials, enable and execute manufacturing activities in support of its product candidate development efforts, submit regulatory submissions, acquire technology and product candidates, enter into strategic license and collaboration arrangements, organize and staff the Company, conduct business planning, establish its intellectual property portfolio, raise capital and provide general and administrative support for these activities.

License, Collaboration and Success Payment Agreements

12 Months Ended

Dec. 31, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

License, Collaboration and Success Payment Agreements

Fred Hutch

License Agreement - In 2018, the Company entered into a license agreement with Fred Hutchinson Cancer Center (“Fred Hutch”) that grants the Company a worldwide, sublicensable license under certain patent rights (exclusive) and certain technology (non-exclusive) to research, develop and commercialize products and processes for all fields of use utilizing CARs and/or T-cell receptors (“TCRs”), subject to certain exceptions.

Collaboration and Success Payments - In 2018, the Company entered into a research and collaboration agreement with Fred Hutch (“Fred Hutch Collaboration Agreement”), pursuant to which it granted Fred Hutch rights to certain success payments. The potential payments for the Fred Hutch success payments are based on multiples of increased value ranging from 10 times to 50 times based on a comparison of the per share fair market value of the Company’s common stock relative to the original $36.58 per share issuance price of the Company’s Series A convertible preferred stock, which converted into an equal number of shares of the Company’s common stock in connection with the closing of the Company’s initial public offering (“IPO”). The aggregate success payments to Fred Hutch are not to exceed $200.0 million, which would only occur upon a 50 times increase in value relative to the original $36.58 per share issuance price of the Company’s Series A convertible preferred stock. Each threshold is associated with a success payment, ascending from $10.0 million at $365.76 per share to $200.0 million at $1,828.80 per share, payable if such threshold is reached during the measurement period. The term of the success payment agreement ends on the earlier to occur of (i) the nine-year anniversary of the date of the agreement and (ii) a change in control transaction. All per-share values, including the original Series A issuance price referenced herein, have been retroactively adjusted to reflect the Reverse Split effected on May 30, 2025. See Note 2, Summary of Significant Accounting Policies, for additional information regarding the Reverse Split.

The following table summarizes the aggregate potential success payments, which are payable to Fred Hutch in cash or cash equivalents, or at the Company’s discretion, publicly-tradeable shares of the Company’s common stock:


Multiple of initial equity value at issuance	10x		20x		30x		40x		50x
Per share common stock price required for payment	$	365.76	$	731.52	$	1,097.28	$	1,463.04	$	1,828.80
Aggregate success payment(s) (in millions)	$	10	$	40	$	90	$	140	$	200

The success payments will be owed if the per share fair value of the Company’s common stock on the contractually specified valuation measurement dates during the term of the success payment agreement equals or exceeds the above outlined multiples. The valuation measurement dates are triggered by the following events: the one-year anniversary of the Company’s IPO and each two-year anniversary of the Company’s IPO thereafter, the closing of a change in control transaction and the last day of the term of the success payment agreement, unless the term has ended due to the closing of a change of control transaction. As of December 31, 2025, no success payments have been incurred as the per share fair value of the Company’s common stock was below the price required for payment.

The success payment liability was $0.4 million and $0.1 million as of December 31, 2025 and 2024, respectively. With respect to the Fred Hutch Collaboration Agreement success payment obligations, the Company recognized success payment expense of $0.3 million for the year ended December 31, 2025, and expense reversals of $0.5 million and $1.9 million for the years ended December 31, 2024 and 2023, respectively, which are recognized in other (expense) income, net.

Stanford

License Agreement - In 2019, the Company entered into a license agreement with The Board of Trustees of the Leland Stanford Junior University (“Stanford”) to license specified patent rights.

Collaboration and Success Payments - In October 2020, the Company entered into a research and collaboration agreement with Stanford (“Stanford Collaboration Agreement”), pursuant to which it granted Stanford rights to certain success payments. The potential payments for the Stanford Collaboration Agreement success payments are based on multiples of increased value ranging from 10 times to 50 times based on a comparison of the per share fair market value of

the Company’s common stock relative to the original $36.58 per share issuance price of the Company’s Series A convertible preferred stock, which converted into an equal number of shares of the Company’s common stock in connection with the closing of the Company’s IPO. The aggregate success payments to Stanford are not to exceed $200.0 million, which would only occur upon a 50 times increase in value relative to the original $36.58 per share issuance price of the Company’s Series A convertible preferred stock. Each threshold is associated with a success payment, ascending from $10.0 million at $365.76 per share to $200.0 million at $1,828.80 per share, payable if such threshold is reached during the measurement period. The term of each success payment agreement ends on the earlier to occur of (i) the nine year anniversary of the date of the agreement and (ii) a change in control transaction. All per-share values, including the original Series A issuance price referenced herein, have been retroactively adjusted to reflect the Reverse Split effected on May 30, 2025. See Note 2, Summary of Significant Accounting Policies, for additional information regarding the Reverse Split.

The following table summarizes the aggregate potential success payments, which are payable to Stanford in cash or cash equivalents, or at the Company’s discretion, publicly-tradeable shares of the Company’s common stock:


Multiple of initial equity value at issuance	10x		20x		30x		40x		50x
Per share common stock price required for payment	$	365.76	$	731.52	$	1,097.28	$	1,463.04	$	1,828.80
Aggregate success payment(s) (in millions)	$	10	$	40	$	90	$	140	$	200

The success payment liability is estimated at the fair value at inception and at each subsequent reporting period and the expense is accreted over the service period of the Stanford Collaboration Agreement as research and development expense through September 2024. As of October 2024, the Company’s associated success payment liability was fully accreted to fair value as Stanford had provided the requisite service obligation to earn the potential success payment consideration. For the year ended December 31, 2024 and future periods, the change in the Stanford success payment liability fair value is recognized in other (expense) income, net. The success payment liability was $0.8 million and $0.3 million as of December 31, 2025 and 2024, respectively. With respect to the Stanford Collaboration Agreement success payment obligations, the Company recognized success expense payment of $0.5 million for the year ended December 31, 2025, and expense reversals of $0.6 million and $0.9 million for the years ended December 31, 2024 and 2023, respectively.

Convertible Preferred Stock (Details)	Dec. 31, 2025 shares
Equity [Abstract]
Convertible preferred stock outstanding (in shares)	0

Leases - Schedule of Operating Lease Commitments Including Expected Lease Incentives to be Received (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Leases [Abstract]
2026	$ 12,959
2027	13,341
2028	13,005
2029	10,398
2030	9,855
Thereafter	2,333
Total undiscounted lease payments	61,891
Less: imputed interest	(10,897)
Total operating lease liabilities	50,994
Operating Lease Liability
Short-term portion of lease liabilities (included in accrued liabilities and other current liabilities)	9,073	$ 7,974
Operating lease liabilities, non-current	41,921	$ 50,994
Total	$ 50,994

Basis of Presentation and Significant Accounting Policies (Details) $ in Thousands		12 Months Ended
	May 30, 2025	Dec. 31, 2025 USD ($) segment	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Class of Stock [Line Items]
Reverse stock split	0.05
Impairment of long-lived assets \| $		$ 1,443	$ 51,297	$ 0
Number of operating segments		1
Number of reportable segments		1
Minimum
Class of Stock [Line Items]
Estimated life (in years)		3 years
Maximum
Class of Stock [Line Items]
Estimated life (in years)		5 years

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 6: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Accrued Liabilities and Other Current Liabilities (Tables)

12 Months Ended

Dec. 31, 2025

Accrued Liabilities and Other Liabilities [Abstract]

Schedule of Accrued Liabilities and Other Current Liabilities

Accrued liabilities and other current liabilities consisted of the following (in thousands):


	December 31,
	2025		2024
SPA put/call	$	11,411	$	—
Accrued compensation and related benefits	11,154		19,235
Accrued research and development expenses	9,117		9,439
Current lease liabilities	9,073		7,974
Other	2,559		2,999
Deferred lease income	2,535		483
Accrued legal	670		692

Total accrued liabilities and other current liabilities	$	46,519	$	40,822

Accrued Liabilities and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Accrued Liabilities and Other Liabilities [Abstract]
SPA put/call	$ 11,411	$ 0
Accrued compensation and related benefits	11,154	19,235
Accrued research and development expenses	9,117	9,439
Current lease liabilities	9,073	7,974
Other	2,559	2,999
Deferred lease income	2,535	483
Accrued legal	670	692
Total accrued liabilities and other current liabilities	$ 46,519	$ 40,822
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total accrued liabilities and other current liabilities	Total accrued liabilities and other current liabilities

Net Loss Per Share	12 Months Ended
Net Loss Per Share	Dec. 31, 2025
Earnings Per Share [Abstract]
Net Loss Per Share	Net Loss Per ShareBasic and diluted net loss per share is calculated by dividing net loss by the weighted-average number of common shares outstanding during the period, without consideration for common stock equivalents. The Company’s potentially dilutive shares, which include unvested RSUs, unvested PSUs and options to purchase common stock, are considered to be common stock equivalents and are only included in the calculation of diluted net loss per share when their effect is dilutive. Shares subject to options to purchase common stock, unvested RSUs and unvested PSUs were all excluded from consideration in the calculation of diluted net loss per share in all periods presented due to their anti-dilutive effects.

Related-Party Transactions - Narrative (Details) $ / shares in Units, ft² in Thousands, $ in Thousands	1 Months Ended
	Jul. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Sep. 30, 2021 USD ($) ft²
Related Party Transaction [Line Items]
Accrued liabilities and other current liabilities		$ 46,519	$ 40,822
Other non-current liabilities		517	3,253
Securities Purchase Agreement
Related Party Transaction [Line Items]
Sale of stock, sold and issued (in shares) \| shares	3,753,752
Sale of stock, price per share (in dollars per share) \| $ / shares	$ 13.32
Related Party
Related Party Transaction [Line Items]
Rentable area (in square feet) \| ft²				18
Sonoma \| Related Party
Related Party Transaction [Line Items]
Rentable area (in square feet) \| ft²				18
Tenant improvements				$ 4,600
Accrued liabilities and other current liabilities		2,500	500
Other non-current liabilities		$ 0	$ 2,500
ARCH Venture Fund XIII \| Related Party \| Securities Purchase Agreement
Related Party Transaction [Line Items]
Sale of stock, sold and issued (in shares) \| shares	900,000
Net proceeds from sale of stock, after underwriting discounts and commissions	$ 12,500
Sale of stock, price per share (in dollars per share) \| $ / shares	$ 13.32
Beneficial ownership of investor after transaction (as a percent)	10.00%

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Amount
U.S. federal statutory tax	$ (57,634)
Change in valuation allowance	53,781
Stock-based compensation	5,830
Fair value adjustment on PIPE	4,029
Other nondeductible items	(2,314)
R&D Tax credits	(3,563)
Worldwide changes in UTB	(115)
Other	(14)
Effective income tax rate	$ 0
Percent
U.S. federal statutory tax	21.00%	21.00%	21.00%
Change in valuation allowance	(19.60%)	(20.39%)	(29.10%)
Stock-based compensation	(2.12%)	(2.17%)	(2.25%)
Fair value adjustment on PIPE	(1.47%)
Other nondeductible items	0.84%
Tax credits	1.30%	2.23%	2.96%
Worldwide changes in UTB	0.04%
Other	0.01%	0.06%	(0.06%)
Effective income tax rate	0.00%	0.00%	0.00%

Subsequent Events (Details) - Common Stock - Subsequent Event - Milestone Closing $ / shares in Units, $ in Millions	Mar. 06, 2026 USD ($) $ / shares shares
Subsequent Event [Line Items]
Sale of stock, sold and issued (in shares) \| shares	1,952,360
Sale of stock, price per share (in dollars per share) \| $ / shares	$ 25.61
Gross proceeds from sale of stock \| $	$ 50.0

Stock-based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands				1 Months Ended	12 Months Ended
	Jan. 01, 2025 shares	Dec. 31, 2024 shares	Nov. 16, 2023 USD ($) grantee $ / shares shares	Jun. 30, 2021	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation cost related to unvested awards not yet recognized \| $					$ 26,600
Expected weighted-average period compensation cost to be recognized (in years)					2 years 4 months 24 days
Clinical development milestones, probable achievement (in shares) \| shares					58,238
Total stock-based compensation expense \| $					$ 41,829	$ 33,144	$ 47,084
Weighted average grant date fair value (in dollars per share) \| $ / shares					$ 10.31	$ 26.00	$ 33.80
Intrinsic value of options exercised \| $					$ 100	$ 2,900	$ 6,500
ICT License Acquisition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Asset acquisition, contingent consideration probable achievement, share-based compensation expense \| $					19,700
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense \| $					$ 28,743	$ 14,577	18,207
Stock option \| 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum exercise price of plan modifications (in dollars per share) \| $ / shares			$ 47.40
Original exercise price lower range (in dollars per share) \| $ / shares			52.20
Original exercise price upper range (in dollars per share) \| $ / shares			$ 359.00
Share-based payment arrangement, plan modification, number of grantees affected \| grantee			200
Shares repriced (in shares) \| shares			1,170,843
Plan modification, exercise price (in dollars per share) \| $ / shares			$ 37.40
Incremental stock-based compensation expense of modifications \| $			$ 8,900
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares) \| shares		281,190			306,415	281,190
Fair value of awards vested during period \| $					$ 1,700	$ 2,000	1,400
Performance-Based Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period (in years)					10 years
Award performance period (in years)					3 years
Clinical development milestones, probable achievement (in shares) \| shares					7,062
Performance-Based Stock Options \| Share-Based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage					50.00%
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period (in years)					3 years	3 years
Service period from the milestone achievement date (in years)					1 year
Total stock-based compensation expense \| $					$ 1,700	$ 1,900	0
Awards outstanding (in shares) \| shares		135,170			65,518	135,170
Fair value of awards vested during period \| $					$ 400	$ 0	$ 0
Maximum \| Performance-Based Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period relative to total shareholder return (in years)					3 years
Awards granted, percentage of target					200.00%
Maximum \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period relative to total shareholder return (in years)						3 years
Minimum \| Performance-Based Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period relative to total shareholder return (in years)					2 years
Awards granted, percentage of target					0.00%
Minimum \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period relative to total shareholder return (in years)						2 years
2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period (in years)				10 years
Proportion of stock outstanding (as a percent)		5.00%
Number of additional shares authorized for issuance (in shares) \| shares	737,188
Vesting period (in years)				4 years
Future issuance of common shares (in shares) \| shares					2,105,974
2021 Plan \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period (in years)				3 years
2021 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Future issuance of common shares (in shares) \| shares					200,833
Purchase of common stock at discount (as a percent)				15.00%
Purchase price in relation to common stock price (as a percent)				85.00%
Awards issued during period (in shares) \| shares					51,799	47,738	49,320

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2025
Retirement Benefits [Abstract]
Employee Benefit Plan	Employee Benefit Plan In January 2019, the Company adopted a 401(k) retirement and savings plan (the “401(k) Plan”) covering all of its employees. The 401(k) Plan allows employees to make pre- and post-tax contributions up to the maximum allowable amount set by the IRS. Beginning in 2022, the Company sponsors a defined-contribution savings plan with matching 401(k) contributions based upon the amount of the employees’ contributions subject to certain limitations. The Company made matching contributions to the 401(k) Plan on behalf of participants of $0.8 million, $1.0 million and $1.2 million for the years ended December 31, 2025, 2024 and 2023, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480266/715-60-50-3

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480126/715-20-S99-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/715/tableOfContent

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

License, Collaboration and Success Payment Agreements (Tables)

12 Months Ended

Dec. 31, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Aggregate Potential Success Payments


Multiple of initial equity value at issuance	10x		20x		30x		40x		50x
Per share common stock price required for payment	$	365.76	$	731.52	$	1,097.28	$	1,463.04	$	1,828.80
Aggregate success payment(s) (in millions)	$	10	$	40	$	90	$	140	$	200


Multiple of initial equity value at issuance	10x		20x		30x		40x		50x
Per share common stock price required for payment	$	365.76	$	731.52	$	1,097.28	$	1,463.04	$	1,828.80
Aggregate success payment(s) (in millions)	$	10	$	40	$	90	$	140	$	200

Income Taxes - Schedule of Changes to Company’s Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Unrecognized Tax Benefits [Roll Forward]
Beginning balance	$ 3,659	$ 400
Additions based on tax position related to the current year	0	1,625
Adjustments based on prior year tax positions	(202)
Adjustments based on prior year tax positions		1,634
Ending balance	$ 3,457	$ 3,659

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2025
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Pursuant to the SPA, the Company exercised the Put Right following achievement of the applicable milestone and, on March 6, 2026, the Company sold and issued 1,952,360 shares of common stock at a purchase price per share of $25.61 at the Milestone Closing, for gross proceeds of approximately $50.0 million.