0001628280-26-034585 | 10-Q | XBRL Viewer | Allogene Therapeutics INC

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Commitments and Contingencies - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 2,344	$ 2,525
Variable lease cost	601	556
Total lease costs	$ 2,945	$ 3,081

Summary of Significant Accounting Policies	3 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2026
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) for interim financial information and pursuant to Form 10-Q and Article 10 of Regulation S-X of the SEC. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the Company’s opinion, all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair presentation of the results of operations and cash flows for the periods presented have been included. The condensed balance sheet as of March 31, 2026, the condensed statements of operations and comprehensive loss for the three months ended March 31, 2026 and 2025, the condensed statements of stockholders’ equity as of March 31, 2026 and 2025, the condensed statements of cash flows for the three months ended March 31, 2026 and 2025, and the financial data and other financial information disclosed in the notes to the condensed financial statements are unaudited. The results of operations for the three months ended March 31, 2026 are not necessarily indicative of the results to be expected for the year ending December 31, 2026, or for any other future annual or interim period. These condensed financial statements should be read in conjunction with the Company’s audited financial statements and related notes for the year ended December 31, 2025, included in the Company’s Annual Report on Form 10-K, filed with the SEC on March 12, 2026 (Annual Report). Use of Estimates The preparation of condensed financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying condensed financial statements include but are not limited to the fair value of common stock, the fair value of stock options, the fair value of investments, income tax uncertainties, the CIRM (as defined below) award liability, and certain accruals. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances change. Actual results could differ from those estimates. Significant Accounting Policies There have been no significant changes to the accounting policies during the three months ended March 31, 2026, as compared to the significant accounting policies described in Note 1 of the “Notes to Financial Statements” in the Company’s audited financial statements included in its Annual Report. Recently Adopted Accounting Pronouncements There have been no new accounting pronouncements issued or effective that are expected to have a material impact on the Company’s condensed financial statements. Recent Accounting Pronouncements Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40), which requires new disclosures to disaggregate prescribed natural expenses underlying any income statement caption. ASU 2024-03 is effective for annual periods in fiscal years beginning after December 15, 2026, and interim periods thereafter. Early adoption is permitted. ASU 2024-03 applies on a prospective basis for periods beginning after the effective date. However, retrospective application to any or all prior periods presented is permitted. The Company is currently assessing the impact ASU 2024-03 will have on the financial statements and disclosures. In September 2025, the FASB issued ASU 2025-06, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which modernizes the accounting for internal-use software costs. ASU 2025-06 removes all references to prescriptive and sequential software development stages throughout Subtopic 350-40. Therefore, an entity is required to start capitalizing software costs when both of the following occur: 1) Management has authorized and committed to funding the software project and 2) It is probable that the project will be completed and the software will be used to perform the function intended. ASU 2025-06 is effective for annual periods beginning after December 15, 2027, with early adoption permitted as of the beginning of an annual period. The Company is currently in the process of evaluating the impact of this pronouncement on the financial statements and disclosures.

Description of Business	3 Months Ended
Description of Business	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Allogene Therapeutics, Inc. (the Company or Allogene) was incorporated on November 30, 2017 in the State of Delaware and is headquartered in South San Francisco, California. Allogene is a clinical stage immuno-oncology company pioneering the development of genetically engineered allogeneic T cell product candidates for the treatment of cancer and autoimmune diseases. The Company is developing a pipeline of off-the-shelf T cell product candidates that are designed to target and kill cancer cells in patients or eliminate pathogenic autoreactive cells in patients with autoimmune disorders. The Company’s engineered T cells are allogeneic, meaning they are derived from healthy donors for intended use in any patient, rather than from an individual patient for that patient’s use, as in the case of autologous T cells. The Company believes this key difference will enable it to deliver readily available treatments faster, more reliably, at greater scale, and to more patients. Public Offerings In November 2019, the Company entered into a sales agreement with TD Securities (USA) LLC (f/k/a Cowen and Company, LLC) (TD Cowen), as amended on November 2, 2022 and November 2, 2023, under which the Company may from time to time issue and sell shares of its common stock through TD Cowen in at-the-market (ATM) offerings. The aggregate compensation payable to TD Cowen as the Company’s sales agent equals up to 3.0% of the gross sales price of the shares sold through TD Cowen pursuant to the sales agreement. The specified dollar limit on the amount of common stock that may be sold under the sales agreement was removed pursuant to the November 2, 2023 amendment to the sales agreement. During the three months ended March 31, 2026, the Company sold an aggregate of 12,476,533 shares of common stock in ATM offerings resulting in net proceeds of $20.7 million. On April 13, 2026, in connection with the Company’s April 2026 Public Offering as described in Notes 9 and 13, the Company suspended any further ATM offering under the TD Cowen sales agreement until a new prospectus or prospectus supplement is filed with the Securities and Exchange Commission (SEC). Need for Additional Capital The Company has sustained operating losses and expects to continue to generate operating losses for the foreseeable future. The Company’s ultimate success depends on the outcome of its research and development activities as well as the ability to commercialize the Company’s product candidates. The Company had cash, cash equivalents and investments of $266.9 million as of March 31, 2026. Since inception through March 31, 2026, the Company has incurred cumulative net losses of $2,053.3 million. Management expects to incur additional losses in the future to fund its operations and conduct product research and development and recognizes the need to raise additional capital to fully implement its business plan. The Company may raise additional capital through the issuance of equity securities, debt financings, collaborations or other sources to further implement its business plan. If additional financing is not available at adequate levels, the Company may need to reevaluate its operating plan and may be required to delay the development of its product candidates. The Company expects that its cash, cash equivalents and investments as of March 31, 2026, together with the net proceeds from the April 2026 Public Offering as described in Notes 9 and 13, will be sufficient to fund its operations for at least the next 12 months from the date the accompanying unaudited condensed financial statements are filed with the SEC.

Commitments and Contingencies - Undiscounted Future Lease Payments (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Commitments and Contingencies Disclosure [Abstract]
2026 (remaining 9 months)	$ 9,897
2027	13,574
2028	14,037
2029	15,437
2030	16,148
2031 and thereafter	33,597
Total undiscounted lease payments	102,690
Less: Present value adjustment	(21,639)
Total	$ 81,051	$ 83,253

Commitments and Contingencies

3 Months Ended

Mar. 31, 2026

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Leases

In August 2018, the Company entered into an operating lease agreement (HQ Lease) for office and laboratory space which consists of approximately 68,000 square feet located in South San Francisco, California. In December 2021, the

Company amended its lease agreement to lease an additional 47,566 square feet of office and laboratory space in South San Francisco, California, as part of the same building as the Company’s current headquarters. The lease term commenced in April 2022. The rent payments for the expansion premises began in August 2022. The lease term for both the existing and expansion premises will expire on March 31, 2032 with an option to extend the term for eight years which is not reasonably assured of exercise.

In October 2018, the Company entered into an operating lease agreement for office and laboratory space which consists of 14,943 square feet located in South San Francisco, California. The lease term will expire March 31, 2032 with an option to extend the term for eight years which is not reasonably assured of exercise.

In February 2019, the Company entered into a lease agreement for approximately 118,000 square feet of space to develop a cell therapy manufacturing facility in Newark, California. The lease term will expire on July 31, 2036 with two ten-year options to extend the lease, both of which are not reasonably assured of exercise.

In February 2023, the Company entered into a sublease with Bellco Capital Advisors Inc. (Bellco) for 2,218 square feet of office space in Los Angeles, California, which was subsequently reduced to 1,944 square feet in February 2026. The sublease term is 115 months, subject to certain early termination rights. The sublease commenced on January 1, 2024.

The Company maintains letters of credit for the benefit of landlords which is disclosed as restricted cash in the condensed balance sheets. Restricted cash related to letters of credit due to landlords was $6.0 million as of March 31, 2026 and December 31, 2025.

The balance sheet classification of the Company’s lease liabilities was as follows (in thousands):


	March 31, 2026		December 31, 2025
Operating lease liabilities
Current portion included in accrued and other current liabilities	$	8,418	$	8,208
Lease liability, noncurrent	72,633		75,045
Total operating lease liabilities	$	81,051	$	83,253

The components of lease costs for operating leases, which were recognized in operating expenses, were as follows (in thousands):


	Three Months Ended March 31,
	2026		2025
Operating lease cost	$	2,344	$	2,525
Variable lease cost	601		556
Total lease costs	$	2,945	$	3,081

The undiscounted future non-cancellable lease payments under the Company’s operating leases as of March 31, 2026 were as follows:


Year ending December 31:	(In thousands)
2026 (remaining 9 months)	$	9,897
2027	13,574
2028	14,037
2029	15,437
2030	16,148
2031 and thereafter	33,597
Total undiscounted lease payments	102,690
Less: Present value adjustment	(21,639)
Total	$	81,051

Operating lease liabilities are based on the net present value of the remaining lease payments over the remaining lease term. In determining the present value of lease payments, the Company uses its estimated incremental borrowing rate. The weighted average discount rate used to determine the operating lease liability was 6.50%. As of March 31, 2026, the weighted average remaining lease term for the Company’s operating leases is 6.94 years.

In December 2024 and January 2025, the Company entered into non-cancelable agreements under which it subleased approximately 46,011 square feet of its HQ Lease to two unaffiliated companies. In July 2025, the Company entered into a non-cancelable agreement under which it subleased one of its leased buildings in South San Francisco to one unaffiliated company. During the three months ended March 31, 2026 and 2025, the Company recognized $0.8 million and $0.3 million, respectively, in sublease income under the interest and other income, net caption within the condensed statements of operations.

Other Commitments

In July 2020, the Company entered into a Solar Power Purchase and Energy Services Agreement for the installation and operation of a solar photovoltaic generating system and battery energy storage system at the Company’s cell therapy manufacturing facility in Newark, California. The agreement has a term of 20 years and commenced in September 2022. The Company is obligated to pay for electricity generated from the system at an agreed rate for the duration of the agreement term. Termination of the agreement by the Company will result in a termination payment due of approximately $4.3 million. In connection with the agreement, the Company maintains a letter of credit for the benefit of the service provider in the amount of $4.3 million which is recorded as restricted cash in the condensed balance sheets as of March 31, 2026 and December 31, 2025.

The Company has entered into certain license agreements for intellectual property which is used as part of its development and manufacturing processes. Each of these respective agreements are generally cancellable by the Company. These agreements require payment of annual license fees and may include conditional milestone payments for achievement of specific research, clinical and commercial events, and royalty payments. The timing and likelihood of any significant conditional milestone payments or royalty payments becoming due was not probable as of March 31, 2026.

Legal Proceedings

In the ordinary course of business, the Company or its business partners are from time to time subject to legal claims and regulatory actions that could have a material adverse effect on its business or financial position. The Company assesses its potential liability in such situations by analyzing the possible outcomes of various litigation, regulatory, and settlement strategies. If the Company determines that a material loss is probable and its amount can be reasonably estimated, it will accrue an amount equal to the estimated loss. As of March 31, 2026, the Company did not accrue any estimated losses related to its ongoing legal proceedings.

Balance Sheet Components (Tables)

3 Months Ended

Mar. 31, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Property and Equipment

Property and Equipment consist of the following:


	March 31, 2026		December 31, 2025
	(In thousands)
Leasehold improvements	$	107,537	$	107,537

Laboratory equipment	28,792		28,748
Computer equipment and purchased software	4,873		4,873
Furniture and fixtures	4,223		4,214
Total	145,425		145,372
Less: accumulated depreciation	(75,402)		(72,533)
Total property and equipment, net	$	70,023	$	72,839

Description of Business (Details) - USD ($) $ in Thousands	3 Months Ended
Description of Business (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Nov. 30, 2019
Subsidiary, Sale of Stock [Line Items]
Stock issuance, maximum compensation due to third party, percent			3.00%
Cash and cash equivalents and marketable securities	$ 266,900
Accumulated deficit	$ (2,053,316)	$ (2,010,709)
ATM offering
Subsidiary, Sale of Stock [Line Items]
Shares sold in offering (in shares)	12,476,533
Sale of stock, consideration received on transaction	$ 20,700

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

License and Collaboration Agreements - Antion (Details) - USD ($) $ in Millions	1 Months Ended
	Jul. 31, 2023	Mar. 31, 2026	Dec. 31, 2025
Antion
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Warrants and rights outstanding	$ 3.0
Antion Collaboration Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Prior investment obligation	3.0
Antion Collaboration Agreement \| Other Noncurrent Assets
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Equity investment		$ 0.0	$ 0.0
Antion Collaboration Agreement \| Preferred Stock
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Preferred stock investment payable	$ 2.0

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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+ Details

Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 145,425	$ 145,372
Less: accumulated depreciation	(75,402)	(72,533)
Total property and equipment, net	70,023	72,839
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	107,537	107,537
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	28,792	28,748
Computer equipment and purchased software
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	4,873	4,873
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 4,223	$ 4,214

License and Collaboration Agreements - Notch Therapeutics (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development	$ 32,003,000	$ 50,200,000
Pre-Clinical Development Milestone \| Notch Therapeutics, Inc. \| Research Collaboration And License Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development	0	$ 0
Notch Therapeutics, Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Equity investment	$ 0		$ 0

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

+ Details

License and Collaboration Agreements - Pfizer (Details) - Asset Contribution Agreement - Pfizer - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone payments	$ 0	$ 0
Royalties payments	$ 0	$ 0

Balance Sheet Components - Additional Information (Details)			3 Months Ended		12 Months Ended
	May 12, 2025	Apr. 26, 2024 USD ($) patient	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)	Apr. 28, 2025 USD ($)
Restructuring Cost and Reserve [Line Items]
Proceeds from CIRM award (Note 5)			$ 0	$ 3,350,000
Interest expense			300,000	150,000
California Institute For Regenerative Medicine (CIRM)
Restructuring Cost and Reserve [Line Items]
Grant award, amount		$ 15,000,000.0				$ 9,200,000
Number of patients treated \| patient		20
Grant award, grantee maximum expected contribution		$ 15,700,000
Grant award, royalty fee, amount due to other party, multiplier		9
Grant award, loan conversion period deadline, anniversary of award		10 years
Basis spread on variable rate		10.00%
Proceeds from CIRM award (Note 5)			9,200,000
Interest expense			300,000	200,000
Accrued interest			1,600,000
California Institute For Regenerative Medicine (CIRM) \| Minimum
Restructuring Cost and Reserve [Line Items]
Converted to loan, repayment percentage		0.80
California Institute For Regenerative Medicine (CIRM) \| Maximum
Restructuring Cost and Reserve [Line Items]
Converted to loan, repayment percentage		1
Workforce Reduction
Restructuring Cost and Reserve [Line Items]
Positions eliminated, percent	28.00%
Restructuring costs			0	$ 0
Restructuring reserve			$ 0
Workforce Reduction \| Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring costs					$ 3,100,000
Workforce Reduction \| General and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs					300,000
Workforce Reduction \| Equipment impairment
Restructuring Cost and Reserve [Line Items]
Restructuring costs					$ 1,300,000

Fair Value Measurements

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Fair Value Measurements

The Company measures and reports its cash equivalents, restricted cash, and investments at fair value.

Money market funds are measured at fair value on a recurring basis using quoted prices and are classified as Level 1. Investments are measured at fair value based on inputs other than quoted prices that are derived from observable market data and are classified as Level 2 inputs, except for investments in U.S. treasury securities which are classified as Level 1.

There were no Level 3 assets or liabilities as of March 31, 2026 and as of December 31, 2025.

Financial assets subject to fair value measurements on a recurring basis and the level of inputs used in such measurements by major security type as of March 31, 2026 and as of December 31, 2025 are presented in the following tables:


	March 31, 2026
	Level 1		Level 2		Level 3		Fair Value
	(In thousands)
Financial Assets:
Money market funds (1)	$	25,055	$	—	$	—	$	25,055
Commercial paper	—		86,739		—		86,739
Corporate bonds	—		69,100		—		69,100
U.S. treasury securities	61,834		—		—		61,834
U.S. agency securities	—		18,904		—		18,904

Total financial assets	$	86,889	$	174,743	$	—	$	261,632


	December 31, 2025
	Level 1		Level 2		Level 3		Fair Value
	(In thousands)
Financial Assets:
Money market funds (1)	$	48,576	$	—	$	—	$	48,576
Commercial paper	—		42,704		—		42,704
Corporate bonds	—		53,705		—		53,705
U.S. treasury securities	76,157		—		—		76,157
U.S. agency securities	—		33,999		—		33,999

Total financial assets	$	124,733	$	130,408	$	—	$	255,141

(1)Included within cash and cash equivalents on the Company’s condensed balance sheets.

- 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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-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

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

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

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

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

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

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

+ Details

Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 261,632	$ 255,141
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	25,055	48,576
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	86,739	42,704
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	69,100	53,705
U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	61,834	76,157
U.S. agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	18,904	33,999
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	86,889	124,733
Level 1 \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	25,055	48,576
Level 1 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 1 \| Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 1 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	61,834	76,157
Level 1 \| U.S. agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	174,743	130,408
Level 2 \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 2 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	86,739	42,704
Level 2 \| Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	69,100	53,705
Level 2 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 2 \| U.S. agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	18,904	33,999
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 3 \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 3 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 3 \| Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 3 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Level 3 \| U.S. agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 0	$ 0

License and Collaboration Agreements - MD Anderson Cancer Center (Details) - University Of Texas M D Anderson Cancer Center - USD ($) $ in Millions		3 Months Ended
	Oct. 06, 2020	Mar. 31, 2026	Mar. 31, 2025
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaboration agreement, term (in years)	5 years
Committed funding	$ 15.0
Committed funding remaining		$ 6.0
Collaboration costs		$ 0.1	$ 0.4

Commitments and Contingencies - Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Commitments and Contingencies Disclosure [Abstract]
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued and other current liabilities	Accrued and other current liabilities
Current portion included in accrued and other current liabilities	$ 8,418	$ 8,208
Lease liability, noncurrent	72,633	75,045
Total operating lease liabilities	$ 81,051	$ 83,253

Segment Reporting (Tables)

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Schedule of Segment Profit or Loss and Segment Expenses

The table below is the summary of the segment profit or loss information, including the significant segment expenses (in thousands):


	Three Months Ended March 31,
	2026		2025

Significant operating expenses:
Cema-cel	$	7,669	$	6,222
All other development costs	1,999		10,390
Payroll	14,444		19,601
Facilities & IT-related spend	6,418		7,319
Supporting external spend	4,372		5,846
Other operating expenses	11,190		15,813
Total operating expenses	46,092		65,191
Other income (expenses), net	3,485		5,458
Net loss	(42,607)		(59,733)

Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2026

Investments, All Other Investments [Abstract]

Schedule of Fair Value and Amortized Cost

The fair value and amortized cost of cash equivalents and available-for-sale securities by major security type as of March 31, 2026 and as of December 31, 2025 are presented in the following tables:


	March 31, 2026
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(In thousands)
Money market funds	$	25,055	$	—	$	—	$	25,055
Commercial paper	86,915		2		(178)		86,739
Corporate bonds	69,145		10		(55)		69,100
U.S. treasury securities	61,791		52		(9)		61,834
U.S. agency securities	18,909		2		(7)		18,904

Total cash equivalents and investments	$	261,815	$	66	$	(249)	$	261,632

Classified as:
Cash equivalents							$	25,055
Short-term investments							236,577
Long-term investments							—
Total cash equivalents and investments							$	261,632


	December 31, 2025
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(In thousands)
Money market funds	$	48,576	$	—	$	—	$	48,576
Commercial paper	42,696		18		(10)		42,704
Corporate bonds	53,636		69		—		53,705
U.S. treasury securities	75,990		167		—		76,157
U.S. agency securities	33,974		25		—		33,999

Total cash equivalents and investments	$	254,872	$	279	$	(10)	$	255,141

Classified as:
Cash equivalents							$	48,576
Short-term investments							198,522
Long-term investments							8,043
Total cash equivalents and investments							$	255,141

- 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
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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

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

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

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

License and Collaboration Agreements - Servier (Details) € in Millions		3 Months Ended
	Feb. 13, 2026 USD ($)	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2026 EUR (€)	May 10, 2024 EUR (€)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development \| $		$ 32,003,000	$ 50,200,000
Regulatory And Sales Milestones
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalties payments \| $		0	0
Servier \| License and Collaboration Agreement \| UNITED STATES
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty rate, percent					10.00%
Reduction to royalty rate, percent					10.00%
Servier \| Regulatory Milestone \| License and Collaboration Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate milestone payments					€ 75.0
Aggregate potential milestone payments, remaining obligation					60.0
Milestone payable per indication					55.0
Milestone payable remaining				€ 50.0
Aggregate potential milestone payable					20.0
Net cash proceeds \| $	$ 23,700,000
Servier \| Sales Milestone \| License and Collaboration Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate milestone payments					€ 80.0
Servier \| Regulatory And Sales Milestones \| License and Collaboration Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development \| $		$ 0	$ 0

Stock-Based Compensation - Schedule of Stock Option Activity (Details) - 2018 Plan - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Number of Options
Beginning balance (in shares)	31,138,077
Options granted (in shares)	6,995,020
Options exercised (in shares)	(2,438)
Options forfeited (in shares)	(214,612)
Ending balance (in shares)	37,916,047	31,138,077
Number of options, exercisable (in shares)	22,823,105
Number of options, vested and expected to vest (in shares)	37,916,047
Weighted- Average Exercise Price
Beginning balance (in dollars per share)	$ 6.31
Options granted (in dollars per share)	1.87
Options exercised (in dollars per share)	1.94
Options forfeited (in dollars per share)	4.81
Ending balance (in dollars per share)	5.50	$ 6.31
Weighted-average exercise price, exercisable (in dollars per share)	7.81
Weighted-average exercise price, vested and expected to vest (in dollars per share)	$ 5.50
Weighted-average remaining contract term, outstanding (in years)	7 years 5 months 23 days	7 years 2 months 1 day
Weighted-average remaining contract term, exercisable (in years)	6 years 3 months 25 days
Weighted-average remaining contract term, vested and expected to vest (in years)	7 years 5 months 23 days
Aggregate intrinsic value, beginning balance	$ 97
Aggregate intrinsic value, ending balance	9,302	$ 97
Aggregate intrinsic value, exercisable	1,282
Aggregate intrinsic value, vested and expected to vest	$ 9,302

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2026
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company has a history of losses and expects to record a loss in 2026. The Company continues to maintain a full valuation allowance against its net deferred tax assets.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477617/942-740-50-1

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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 740
-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
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-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

License and Collaboration Agreements - Foresight Diagnostics (Details) - USD ($) $ in Thousands			3 Months Ended
	Feb. 19, 2025	Jan. 03, 2024	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development			$ 32,003	$ 50,200
Accrued and other current liabilities			23,397		$ 28,244
Foresight Diagnostics Collaboration Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Committed funding	$ 37,300	$ 26,200
Research and development			2,500	$ 1,300
Foresight Diagnostics Collaboration Agreement \| Current Accrued and Other Liabilities
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Accrued and other current liabilities			$ 2,500		$ 1,400

Net Loss Per Share (Details) - shares	3 Months Ended
Net Loss Per Share (Details) - shares	Mar. 31, 2026	Mar. 31, 2025
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of diluted net loss per share (in shares)	55,046,291	51,421,484
Stock options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of diluted net loss per share (in shares)	37,916,047	31,532,800
Restricted stock units outstanding (Excluding vested but unreleased shares, which are included in weighted-average common shares outstanding)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of diluted net loss per share (in shares)	15,720,910	18,079,422
Expected shares to be purchased under Employee Stock Purchase Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of diluted net loss per share (in shares)	1,409,334	1,809,262

Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	$ 8,270	$ 12,175
Research and development
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	2,696	5,040
General and administrative
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	$ 5,574	$ 7,135

Related Party Transactions	3 Months Ended
Related Party Transactions	Mar. 31, 2026
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Collaboration Revenue and Equity Method Investment In December 2020, the Company entered into the License Agreement with Overland Therapeutics, a corporate joint venture entity and related party (see Note 6). The License Agreement was subsequently assigned to a wholly-owned subsidiary of Allogene Overland, Allogene Overland HK. On April 1, 2022, Allogene Overland HK assigned the License Agreement to Allogene Overland Biopharm (PRC) Co., Limited. On May 24, 2024, the License Agreement was amended. On May 12, 2026, the License Agreement was terminated. Sublease Agreement In December 2018, the Company entered into a sublease with Bellco Capital LLC (Bellco) for 1,293 square feet of office space in Los Angeles, California for a three year term. On April 1, 2020, Bellco assumed all rights, title, interests and obligations under the sublease from Bellco. In November 2021, the sublease was extended to June 30, 2025. The sublease was amended, effective in July 2022, to move to a nearby location, with office space of 737 square feet. In 2023, the Company exercised its early termination right under the sublease agreement and the sublease was terminated effective December 31, 2023. In February 2023, the Company entered into a new sublease agreement with Bellco for 2,218 square feet of office space in Los Angeles, California, which was subsequently reduced to 1,944 square feet in February 2026. The Company’s executive chairman, Arie Belldegrun, M.D., is a trustee of the Belldegrun Family Trust, which controls Bellco. The sublease term is 115 months, subject to certain early termination rights. The sublease commenced on January 1, 2024. The total right of use asset and associated lease liability recorded related to this related party lease were $2.0 million and $2.0 million, respectively, as of March 31, 2026. The Company paid approximately $0.2 million towards its share of the security deposit. Rent expense related to this sublease were $0.1 million and $0.1 million for the three months ended March 31, 2026 and 2025, respectively. Consulting Agreements In August 2018, the Company entered into a consulting agreement with Bellco. Pursuant to the consulting agreement, Bellco provides certain services for the Company, which are performed by Dr. Belldegrun, the Company’s executive chair, and include without limitation, providing advice and analysis with respect to the Company’s business, business strategy and potential opportunities in the field of allogeneic CAR T cell therapy and any other aspect of the CAR T cell therapy business as the Company may agree. In consideration for these services, the Company paid Bellco $40,217 per month in arrears commencing January 2022. Effective January 2026, the monthly consulting service fee was increased by 2% to $41,021 per month. The Company may also, at its discretion, pay Bellco an annual performance award in an amount up to 60% of the aggregate compensation payable to Bellco in a calendar year. The Company also reimburses Bellco for out of pocket expenses incurred in performing the services. The costs incurred for services provided, bonus, and out-of-pocket expenses incurred under this consulting agreement were $0.2 million and $0.2 million for the three months ended March 31, 2026 and 2025, respectively. Co-Manager Agreement On April 14, 2026, the Company entered into an underwriting agreement (Underwriting Agreement) with Goldman Sachs & Co. LLC, Jefferies LLC and TD Securities (USA) LLC, as representatives of the several underwriters named therein (Underwriters), relating to the issuance and sale in a public offering of shares of the Company’s common stock (April 2026 Public Offering). On April 16, 2026, the Company sold 100,200,000 shares to the Underwriters. The price to the public in the offering was $2.00 per share. The underwriting discount was $0.12 per share. TPG Capital BD, LLC served as an Underwriter for the offering and purchased an aggregate of 3,807,600 shares from the Company at a price of $1.88 per share, resulting in an aggregate underwriting discount to TPG Capital BD, LLC of approximately $0.5 million. Todd Sisitsky, a member of the Company’s Board of Directors, has served as President and on the Board of Directors of TPG Inc., an affiliate of TPG Capital BD, LLC, since TPG Inc.’s inception.

- Definition

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

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+ Details

Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2026	May 11, 2026
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Transition Report	false
Entity File Number	001-38693
Entity Registrant Name	Allogene Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-3562771
Entity Address, Address Line One	210 East Grand Avenue
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	457-2700
Title of 12(b) Security	Common Stock, $0.001 par value per share
Trading Symbol	ALLO
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		345,154,561
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity Central Index Key	0001737287
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q1

Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future issuance (in shares)	8,964,856
Total stock-based compensation	$ 8,270,000	$ 12,175,000
Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 0	0
Certain Executive Officers And Other Employees \| Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based restricted stock units (in shares)	4,689,631
Restricted stock units, granted (in shares)	0
Certain Executive Officers And Other Employees \| Restricted Stock Units (RSUs) With Market Condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based restricted stock units (in shares)	0
Total stock-based compensation	$ 0	$ 100,000

- Definition

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

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+ Details

Segment Reporting

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Segment Reporting

The Company has one reportable segment related to developing and commercializing genetically engineered allogeneic T cell product candidates for the treatment of cancer and autoimmune diseases. The segment derives its current revenues from research and development collaborations.

The CEO, as the chief operating decision maker, manages and allocates resources for the Company’s operations at a consolidated company basis by assessing how to best deploy available resources across functions and research and development projects. The CEO uses consolidated, single-segment financial information for purposes of evaluating performance, planning and forecasting future period financial results, and allocating resources.

The table below is the summary of the segment profit or loss information, including the significant segment expenses (in thousands):


	Three Months Ended March 31,
	2026		2025

Significant operating expenses:
Cema-cel	$	7,669	$	6,222
All other development costs	1,999		10,390
Payroll	14,444		19,601
Facilities & IT-related spend	6,418		7,319
Supporting external spend	4,372		5,846
Other operating expenses	11,190		15,813
Total operating expenses	46,092		65,191
Other income (expenses), net	3,485		5,458
Net loss	(42,607)		(59,733)

Cema-cel includes external development and clinical trial costs related to ALPHA3, ALPHA2, CLL, and ALLO-501 programs. All other development costs include external development and clinical trial costs related to ALLO-329, ALLO-316, ALLO-647, BCMA, and other programs. Supporting external spend includes professional services, research and development lab supplies and other supporting activities related to the research and development and other business operations. Other operating expenses are primarily related to non-cash expenses such as stock-based compensation, impairment, and depreciation and amortization. The measure of segment assets is reported on the balance sheets as total assets. Primarily, all revenue generated and all long-lived assets are maintained in the United States.

- Definition

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-Name Accounting Standards Codification
-Section 55
-Paragraph 54
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-54

Reference 17: http://www.xbrl.org/2003/role/exampleRef
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-Subparagraph (d)
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Stock-Based Compensation - Schedule of Restricted Stock Units Activity (Details) - Restricted Stock Unit - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Restricted Stock Units
Restricted stock units, unvested, beginning balance (in shares)	16,528,226
Restricted stock units, granted (in shares)	3,854,459
Restricted stock units, Released (in shares)	(2,482,047)
Restricted stock units, forfeited (in shares)	(1,941,228)
Restricted stock units, unvested, ending balance (in shares)	15,959,410	16,528,226
Restricted stock units, expected to vest (in shares)	15,959,410
Restricted stock units, vested and unreleased (in shares)	238,500
Weighted- Average Grant Date Fair Value per Share
Weighted-average fair value at date of grant per share, beginning balance (in dollars per share)	$ 2.99
Weighted-average fair value at date of grant per share, granted (in dollars per share)	1.87
Weighted-average fair value at date of grant per share, Released (in dollars per share)	3.69
Weighted-average fair value at date of grant per share, forfeited (in dollars per share)	2.59
Weighted-average fair value at date of grant per share, ending balance (in dollars per share)	2.66	$ 2.99
Weighted-average fair value at date of grant per share, expected to vest (in dollars per share)	2.66
Weighted-average fair value at date of grant per share, vested and unreleased (in dollars per share)	$ 1.29
Weighted average remaining vesting life, unvested (in years)	2 years 9 months 21 days	2 years 4 months 20 days
Weighted average remaining vesting life, expected to vest (in years)	2 years 9 months 21 days
Aggregate intrinsic value, unvested	$ 38,941	$ 22,644
Aggregate intrinsic value, expected to vest	38,941
Aggregate intrinsic value, vested and unreleased	$ 582

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Financial Assets and Liabilities Subject to Fair Value Measurements on Recurring Basis and Level of Inputs Used in Such Measurements by Major Security Type


	March 31, 2026
	Level 1		Level 2		Level 3		Fair Value
	(In thousands)
Financial Assets:
Money market funds (1)	$	25,055	$	—	$	—	$	25,055
Commercial paper	—		86,739		—		86,739
Corporate bonds	—		69,100		—		69,100
U.S. treasury securities	61,834		—		—		61,834
U.S. agency securities	—		18,904		—		18,904

Total financial assets	$	86,889	$	174,743	$	—	$	261,632


	December 31, 2025
	Level 1		Level 2		Level 3		Fair Value
	(In thousands)
Financial Assets:
Money market funds (1)	$	48,576	$	—	$	—	$	48,576
Commercial paper	—		42,704		—		42,704
Corporate bonds	—		53,705		—		53,705
U.S. treasury securities	76,157		—		—		76,157
U.S. agency securities	—		33,999		—		33,999

Total financial assets	$	124,733	$	130,408	$	—	$	255,141

(1)Included within cash and cash equivalents on the Company’s condensed balance sheets.

License and Collaboration Agreements - Overland Therapeutics, Inc. (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	May 12, 2026	Dec. 31, 2025	May 24, 2024	Dec. 14, 2020
Overland Therapeutics (Formerly Known As Allogene Overland)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Ownership percentage						49.00%
Equity method investments	$ 0			$ 0
Collaboration revenue - related party	$ 0	$ 0
Overland Therapeutics (Formerly Known As Allogene Overland) \| Voting Interest
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Ownership percentage	20.00%
Overland Therapeutics (Formerly Known As Allogene Overland) \| Voting Interest \| Subsequent Event
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Ownership percentage			3.00%
Overland Therapeutics (Formerly Known As Allogene Overland) \| License
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenue, remaining performance obligation, amount	$ 4,600,000			$ 4,600,000
Overland Therapeutics (Formerly Known As Allogene Overland) \| License \| Maximum
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenue, remaining performance obligation, variable consideration amount					$ 115,000,000.0
Overland Pharmaceuticals Inc. \| Overland Therapeutics (Formerly Known As Allogene Overland)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Ownership percentage						51.00%
Overland Therapeutics (Formerly Known As Allogene Overland)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Subsidiary, ownership percentage, noncontrolling owner					18.00%
License agreement, minimum ownership threshold, percent					0.075
Overland Therapeutics (Formerly Known As Allogene Overland) \| Overland Pharmaceuticals Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Subsidiary, ownership percentage, parent					82.00%
Overland US \| Overland Pharmaceuticals Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Subsidiary, ownership percentage, parent					100.00%

Commitments and Contingencies - Additional Information (Details) $ in Millions	1 Months Ended				2 Months Ended	3 Months Ended
	Feb. 28, 2026 ft²	Jul. 31, 2025 company property	Feb. 28, 2023 ft²	Feb. 28, 2019 ft² renewal	Jan. 31, 2025 ft² company	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2021 ft²	Jul. 31, 2020 USD ($)	Oct. 31, 2018 ft²	Aug. 31, 2018 ft²
Operating Leased Assets [Line Items]
Letter of credit \| $						$ 6.0		$ 6.0
Weighted average discount rate, percent						6.50%
Weighted average remaining lease term (in years)						6 years 11 months 8 days
Sublease income \| $						$ 0.8	$ 0.3
Agreement term (in years)										20 years
Termination payment \| $										$ 4.3
Letter of Credit
Operating Leased Assets [Line Items]
Letter of credit \| $						$ 4.3		$ 4.3
Bellco \| Sublease Agreement \| Related Party
Operating Leased Assets [Line Items]
Area of office space (in square feet)	1,944		2,218
Sublease, term of contract (in years)			115 months
Newark, California
Operating Leased Assets [Line Items]
Operating lease, extended term (in years)				10 years
Area of operating lease (in square feet)				118,000
Number of options to extend lease \| renewal				2
South San Francisco, California
Operating Leased Assets [Line Items]
Area of lease (in square feet)											14,943	68,000
Additional area of lease (in square feet)									47,566
Operating lease, extended term (in years)									8 years		8 years
HQ Lease
Operating Leased Assets [Line Items]
Area of office space (in square feet)					46,011
Number of unaffiliated company lessees \| company					2
South San Francisco Building Two
Operating Leased Assets [Line Items]
Number of unaffiliated company lessees \| company		1
Number of properties to be subleased \| property		1

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2026
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Equity Financing On April 16, 2026, the Company closed the April 2026 Public Offering in which it sold 100,200,000 shares of its common stock at a public offering price of $2.00 per share, including 12,700,000 additional shares sold pursuant to the Underwriters’ partial exercise of their option to purchase additional shares. The aggregate gross proceeds were $200.4 million and the aggregate net proceeds were approximately $187.9 million, after deducting underwriting discounts and commissions and estimated offering expenses payable by the Company. Overland License Termination and Equity Restructuring Subsequent to March 31, 2026, the Company entered into a termination agreement with Overland Therapeutics (SH) Co. Ltd. and Overland Therapeutics, Inc., pursuant to which the License Agreement, as defined in Note 6, was terminated in its entirety. Refer to Note 6 for disclosure under the heading “Investment in and License Agreement with Overland Therapeutics, Inc.”

Fair Value Measurements - Additional Information (Details) - Level 3 - Fair Value, Measurements, Recurring - USD ($)	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	$ 0	$ 0
Financial liabilities	$ 0	$ 0

Balance Sheet Components

3 Months Ended

Mar. 31, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Components

Property and Equipment, Net

Property and Equipment consist of the following:


	March 31, 2026		December 31, 2025
	(In thousands)
Leasehold improvements	$	107,537	$	107,537

Laboratory equipment	28,792		28,748
Computer equipment and purchased software	4,873		4,873
Furniture and fixtures	4,223		4,214
Total	145,425		145,372
Less: accumulated depreciation	(75,402)		(72,533)
Total property and equipment, net	$	70,023	$	72,839

Accrued and Other Current Liabilities

On May 12, 2025, the Company’s Board of Directors approved an approximately 28% reduction in the Company’s employee workforce (Workforce Reduction) in connection with a reduction in manufacturing operations and a reprioritization of resources to focus on the Company’s clinical programs. The Workforce Reduction included one-time severance payments and other employee benefits and resulted in impairment of equipment. During the year ended December 31, 2025, the Company

recorded $3.1 million, $0.3 million, and $1.3 million in research and development expense, general and administrative expense, and equipment impairment, respectively, in the statement of operations and comprehensive loss. There were no such costs for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026, there were no remaining severance and other employee benefits accruals.

California Institute for Regenerative Medicine (CIRM) Award

On April 26, 2024, the Company was awarded up to $15.0 million from CIRM to support the clinical development of ALLO-316, an AlloCAR T investigational product targeting CD70 in development for the treatment of advanced or metastatic renal cell carcinoma (RCC). Upon treatment of 20 patients, the Company met the primary study objectives of the ALLO-316 Phase 1b study plan supported by CIRM and was able to successfully complete the study plan on time and under budget without further enrollment. As a result, the Company updated the study plan and requested a reduction in its co-funding responsibility and adjustments to the remaining milestone payments to align with the updated research plan. On April 28, 2025, the terms of the award were amended, and the total award amount was adjusted to up to $9.2 million.

Pursuant to terms of the award, the disbursements are tied to the achievement of specified operational milestones. In addition, the terms of the award and amended award include a co-funding requirement pursuant to which the Company is required to spend up to approximately $15.7 million of its own capital to fund the CIRM funded research project. The award was made in accordance with the CIRM Grants Administration Policy for Clinical Stage Projects which may require the award to be repaid by the Company. Under the terms of the CIRM award, the Company is obligated to pay royalties based on a low single digit royalty percentage on net sales of CIRM-funded product candidate. The maximum royalty that the Company may be required to pay to CIRM is equal to nine times the total amount awarded and paid to the Company.

After completing the CIRM funded research project and at any time after the award period end date (but no later than the ten-year anniversary of the date of the award), the Company has the right, upon its election, to convert the award into a loan. The terms of conversion into a loan will be determined based on various factors and could result in 80% to 100% plus interest at 10% per annum plus the Secured Overnight Financing Rate of the total award dependent upon the phase of clinical development of the product candidate at the time of the Company’s election to be repaid to CIRM.

No income associated with the CIRM award will be recognized until it is confirmed with CIRM that the award does not require repayment. Upon cash receipt, the CIRM award and accrued interest will be recognized as other long-term liabilities on the condensed balance sheets. The Company will not recognize a receivable of future awards until it is approved by CIRM.

The Company received $9.2 million from CIRM through March 31, 2026 and accounted for the proceeds as a liability within other long-term liabilities on the condensed balance sheets. The Company recorded interest expense of $0.3 million and $0.2 million for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026, $1.6 million of accrued interest was included in other long-term liabilities.

Related Party Transactions (Details)			1 Months Ended					3 Months Ended
Related Party Transactions (Details)	Apr. 16, 2026 USD ($) $ / shares shares	Jan. 31, 2026 USD ($)	Feb. 28, 2026 ft²	Feb. 28, 2023 USD ($) ft²	Jul. 31, 2022 ft²	Dec. 31, 2018 ft²	Aug. 31, 2018 USD ($)	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
Related Party Transaction [Line Items]
Operating lease right-of-use asset								$ 38,819,000		$ 39,888,000
Operating lease liability								81,051,000		$ 83,253,000
Non-cash rent expense								1,069,000	$ 1,130,000
April 2026 Public Offering \| Subsequent Event
Related Party Transaction [Line Items]
Shares sold in offering (in shares) \| shares	100,200,000
Offering price (in dollars per share) \| $ / shares	$ 2.00
Underwriting discount (in dollars per share) \| $ / shares	$ 0.12
Related Party \| Sublease Agreement \| Bellco
Related Party Transaction [Line Items]
Area of office space (in square feet) \| ft²			1,944	2,218
Area of office space (in square feet) \| ft²					737
Sublease, term of contract (in months)				115 months
Operating lease right-of-use asset								2,000,000.0
Operating lease liability								2,000,000.0
Operating lease, base rent and security deposit, payment				$ 200,000
Non-cash rent expense								100,000	100,000
Related Party \| Consulting Agreements \| Bellco
Related Party Transaction [Line Items]
Related party transaction service fee increased percentage		2.00%
Related party transaction monthly service fees increased		$ 41,021
Cost of revenue								$ 200,000	$ 200,000
Related Party \| Consulting Agreements \| Maximum \| Bellco
Related Party Transaction [Line Items]
Related party transaction compensation percentage							60.00%
Related Party \| Consulting Agreements \| Payments Commencing January 2021 \| Bellco
Related Party Transaction [Line Items]
Related party transaction monthly payment in arrears							$ 40,217
Related Party \| Co-Manager Agreement \| TPG Capital BD, LLC \| April 2026 Public Offering \| Subsequent Event
Related Party Transaction [Line Items]
Shares sold in offering (in shares) \| shares	3,807,600
Offering price (in dollars per share) \| $ / shares	$ 1.88
Underwriting discount	$ 500,000
CALIFORNIA \| Related Party \| Sublease Agreement \| Bellco
Related Party Transaction [Line Items]
Area of office space (in square feet) \| ft²						1,293
Operating lease term (in months)						3 years

Segment Reporting - Narrative (Details)	3 Months Ended
Segment Reporting - Narrative (Details)	Mar. 31, 2026 segment
Segment Reporting [Abstract]
Number of reportable segments	1
Number of operating segments	1

Segment Reporting - Segment Profit or Loss and Segment Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Significant operating expenses:
Total operating expenses	$ 46,092	$ 65,191
Other income (expenses), net	3,485	5,458
Net loss	(42,607)	(59,733)
Reportable Segment
Significant operating expenses:
Cema-cel	7,669	6,222
All other development costs	1,999	10,390
Payroll	14,444	19,601
Facilities & IT-related spend	6,418	7,319
Supporting external spend	4,372	5,846
Other operating expenses	11,190	15,813
Total operating expenses	46,092	65,191
Other income (expenses), net	3,485	5,458
Net loss	$ (42,607)	$ (59,733)

Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 30,309	$ 51,688
Short-term investments	236,577	198,522
Prepaid expenses and other current assets	6,407	7,539
Total current assets	273,293	257,749
Long-term investments	0	8,043
Operating lease right-of-use asset	38,819	39,888
Property and equipment, net	70,023	72,839
Deposit placed in escrow	0	23,479
Restricted cash	10,292	10,292
Other long-term assets	3,531	3,615
Total assets	395,958	415,905
Current liabilities:
Accounts payable	4,933	4,270
Accrued and other current liabilities	23,397	28,244
Total current liabilities	28,330	32,514
Lease liability, noncurrent	72,633	75,045
Other long-term liabilities	16,120	15,804
Total liabilities	117,083	123,363
Commitments and Contingencies (Notes 6 and 7)
Stockholders’ equity:
Preferred stock, $0.001 par value: 10,000,000 shares authorized as of March 31, 2026 and December 31, 2025; no shares were issued and outstanding as of March 31, 2026 and December 31, 2025	0	0
Common stock, $0.001 par value: 400,000,000 shares authorized as of March 31, 2026 and December 31, 2025; 244,816,413 and 229,413,523 shares issued and outstanding as of March 31, 2026 and December 31, 2025, respectively	245	229
Additional paid-in capital	2,332,129	2,302,753
Accumulated deficit	(2,053,316)	(2,010,709)
Accumulated other comprehensive income (loss)	(183)	269
Total stockholders’ equity	278,875	292,542
Total liabilities and stockholders’ equity	$ 395,958	$ 415,905

Condensed Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Operating expenses:
Research and development	$ 32,003	$ 50,200
General and administrative	14,089	14,991
Total operating expenses	46,092	65,191
Loss from operations	(46,092)	(65,191)
Other income (expenses), net:
Interest and other income, net	3,573	5,516
Interest expense	(300)	(150)
Other income (expenses), net	212	92
Total other income (expenses), net	3,485	5,458
Net loss	(42,607)	(59,733)
Other comprehensive income (loss):
Net unrealized gain (loss) on available-for-sale investments	(452)	132
Net comprehensive loss	$ (43,059)	$ (59,601)
Net loss per share, basic (in dollars per share)	$ (0.18)	$ (0.28)
Net loss per share, diluted (in dollars per share)	$ (0.18)	$ (0.28)
Weighted-average number of shares used in computing net loss per share, basic (in shares)	240,290,782	215,358,619
Weighted-average number of shares used in computing net loss per share, diluted (in shares)	240,290,782	215,358,619

Stock-Based Compensation

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

As of March 31, 2026, there were 8,964,856 shares reserved by the Company under the 2018 Equity Incentive Plan (the 2018 Plan) for the future issuance of equity awards.

Stock Option Activity

The following summarizes option activity under the 2018 Plan:


	Outstanding Options
	Number of Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contract Term	Aggregate Intrinsic Value
				(in years)	(in thousands)
Balance as of December 31, 2025	31,138,077	$	6.31	7.17	$	97
Options granted	6,995,020	1.87

Options exercised	(2,438)	$	1.94
Options forfeited	(214,612)	4.81
Balance as of March 31, 2026	37,916,047	5.50		7.48	$	9,302
Exercisable as of March 31, 2026	22,823,105	7.81		6.32	$	1,282
Vested and expected to vest as of March 31, 2026	37,916,047	$	5.50	7.48	$	9,302

Restricted Stock Unit Activity

The following summarizes restricted stock unit activity under the 2018 Plan:


	Outstanding Restricted Stock Units
	Restricted Stock Units	Weighted- Average Grant Date Fair Value per Share		Weighted Average Remaining Vesting Life	Aggregate Intrinsic Value
				(in years)	(in thousands)
Balance as of December 31, 2025	16,528,226	$	2.99	2.39	$	22,644
Granted	3,854,459	1.87
Released	(2,482,047)	3.69
Forfeited	(1,941,228)	2.59
Balance as of March 31, 2026	15,959,410	2.66		2.81	$	38,941
Expected to vest as of March 31, 2026	15,959,410	$	2.66	2.81	$	38,941
Vested and unreleased as of March 31, 2026	238,500	$	1.29		$	582

As of March 31, 2026, the Company had 4,689,631 outstanding performance-based restricted stock units. No performance-based restricted stock units were granted during the three months ended March 31, 2026. These awards are subject to the holders’ continuous service to the Company through each applicable vesting event. Through March 31, 2026, the Company believes that the achievement of the requisite performance conditions for these awards are not probable. As a result, no compensation expense has been recognized related to the performance-based restricted stock units in the three months ended March 31, 2026 and 2025.

As of March 31, 2026, the Company had zero outstanding restricted stock units with a market condition to certain executive officers and other employees pursuant to the 2018 Plan. Stock-based compensation expense recognized related to the restricted stock units with a market condition was zero and less than $0.1 million for the three months ended March 31, 2026 and 2025, respectively.

Stock-based compensation expense

For the three months ended March 31, 2026 and 2025, the following table presents stock-based compensation expense related to stock options, restricted stock units and employee stock purchase plans that was recorded as research and development and general and administrative expense in its condensed statements of operations and comprehensive loss:


	Three Months Ended March 31,
	2026		2025
Research and development	$	2,696	$	5,040
General and administrative	5,574		7,135
Total stock-based compensation	$	8,270	$	12,175

License and Collaboration Agreements	3 Months Ended
License and Collaboration Agreements	Mar. 31, 2026
Research and Development [Abstract]
License And Collaboration Agreements	License and Collaboration Agreements Asset Contribution Agreement with Pfizer In April 2018, the Company entered into an Asset Contribution Agreement (the Pfizer Agreement) with Pfizer pursuant to which the Company acquired certain assets and assumed certain liabilities from Pfizer, including agreements with Cellectis S.A. (Cellectis) and Servier as described below, and other intellectual property for the development and administration of chimeric antigen receptor (CAR) T cells for the treatment of cancer. The Company is required to make payments upon the achievement of certain sales and regulatory milestones and pay royalties on certain net sales pursuant to the Pfizer Agreement as further described in Note 6 to the Annual Report. For the three months ended March 31, 2026 and 2025, no milestones were achieved and no royalty payments were made. Research Collaboration and License Agreement with Cellectis As part of the Pfizer Agreement, Pfizer assigned to the Company a Research Collaboration and License Agreement (the Original Cellectis Agreement) with Cellectis S.A. (Cellectis). On March 8, 2019, the Company entered into a License Agreement (the Cellectis Agreement) with Cellectis and terminated the Original Cellectis Agreement. Pursuant to the Cellectis Agreement, Cellectis granted to the Company an exclusive, worldwide, royalty-bearing license, on a target-by-target basis, with sublicensing rights under certain conditions, under certain of Cellectis’s intellectual property, including its TALEN and electroporation technology, to make, use, sell, import, and otherwise exploit and commercialize CAR T products directed at certain targets, including B-cell maturation antigen (BCMA), CD70, Claudin 18.2, DLL3 and FLT3 (the Allogene Targets), for human oncologic therapeutic, diagnostic, prophylactic and prognostic purposes. The Company is required to make payments upon the achievement of certain development and sales milestones and pay royalties on certain net sales pursuant to the Cellectis Agreement as further described in Note 6 to the Annual Report. In April 2026, the Company received correspondence from Life Technologies Corporation (LTC), a subsidiary of Thermo Fisher Scientific, asserting that Cellectis had sublicensed to the Company or otherwise made available rights under certain patents licensed by LTC to Cellectis relating to TALEN technology, and that LTC had terminated its license agreements with Cellectis. Cellectis separately informed the Company that LTC had purported to terminate certain license agreements with Cellectis and commenced an arbitration against Cellectis and Cellectis Bioresearch before the American Arbitration Association. Cellectis also informed the Company that it disputes the purported termination and the claims asserted by LTC. The Company is not a party to the arbitration and is evaluating the potential impact, if any, on its rights under the Cellectis Agreement and its other rights relating to product candidates that use TALEN technology. For the three months ended March 31, 2026 and 2025, no milestones were achieved and no royalty payments were made. Exclusive License Agreement with Servier As part of the Pfizer Agreement, Pfizer assigned to the Company an Exclusive License Agreement (the Original Servier Agreement), with Les Laboratoires Servier SAS and Institut de Recherches Internationales Servier SAS (collectively, Servier) to develop, manufacture and commercialize certain allogeneic anti-CD19 CAR T cell product candidates, including UCART19, in the United States with the option to obtain the rights over additional anti-CD19 product candidates and for allogeneic CAR T cell product candidates directed against one additional target. In October 2019, the Company agreed to waive its rights to the one additional target. On May 10, 2024, the Company and Servier entered into an Amendment and Settlement Agreement (the Servier Amendment) which restructured the parties’ relationship under the Original Servier Agreement (as amended, the Servier Agreement). The Company’s licensed territory was expanded to include the European Union and the United Kingdom. The Company was also granted an option to further extend its licensed territory to include China and Japan upon the objective showing of sufficient resources to develop licensed products in those countries, which could be met through the Company entering into a strategic partnership covering those countries. Additionally, the Company agreed to waive certain of its rights under the Original Servier Agreement to elect a conversion of its license to the products directed against CD19, including UCART19, ALLO-501 and cemacabtagene ansegedleucel (cema-cel, previously ALLO-501A) (collectively, CD19 Products) to a worldwide license. Under the Servier Agreement, the Company is required to use commercially reasonable efforts to develop, manufacture and commercialize a CD19 Product. Under the Servier Agreement, Servier sublicenses to the Company certain rights which Servier licenses from Cellectis pursuant to a License, Development and Commercialization Agreement by and between Cellectis and Servier, dated February 7, 2014, as amended by Amendment No. 1 to the License, Development and Commercialization Agreement, dated March 4, 2020 (as amended, the Servier-Cellectis Agreement). As amended by the Servier Amendment, all of the Company’s future milestone payments (regulatory and sales) under the Original Servier Agreement were modified to be the same as, and to coincide with, Servier’s milestone payments to Cellectis that are required under the Servier-Cellectis Agreement. The Servier Agreement provides for aggregate potential milestone payments by the Company to Servier of up to €75.0 million upon successful completion of various regulatory milestones and first commercial sale milestones in the United States, European Union and the United Kingdom for the initial indication of each licensed product, of which €60.0 million remains for the initial indication for cema-cel, with additional payments of €55.0 million, due for each subsequent indication, of which €50.0 million remains for the first subsequent indication for cema-cel, and aggregate potential payments by the Company to Servier of up to €80.0 million upon achievement of certain net sales milestones for each licensed product. Should Servier’s rights and obligations under the Servier-Cellectis Agreement be assigned to the Company, these milestone payments would terminate, and the Company would assume Servier’s milestone payment obligations to Cellectis. In the absence of any such assignment, Servier will remain responsible for making milestone payments that may be due to Cellectis under the Servier-Cellectis Agreement. The Company previously transferred €20.0 million into an escrow account in connection with a potential future milestone payment, which is included in the remaining €60.0 million in milestone payments referenced above for the initial indication for cema-cel. The milestone would have been payable upon the occurrence of certain development, regulatory or adjudicative events. On December 15, 2025, an arbitral tribunal issued a decision providing for a partial termination of the Servier-Cellectis Agreement with respect to UCART19V1 (ALLO-501), which the Company previously abandoned in favor of cema-cel (formerly known as ALLO-501A). As a result, the Company's Servier license covering UCART19V1/ALLO-501 was terminated and Cellectis was required, at the Company's request, to engage in good-faith discussions regarding a direct license. On February 13, 2026, the €20.0 million balance in escrow was remitted to the Company, resulting in net cash proceeds of $23.7 million. The Company is obligated to pay to Servier royalties on annual net sales of any licensed products that are commercialized by the Company that are directed at CD19. Such royalties include tiered royalties on annual net sales in the United States and a flat royalty on annual net sales in territories outside the United States. The United States royalty rates are in a range from the low tens to the mid teen percentages and the ex-U.S. royalty rate is 10%. Such royalties may be reduced for interchangeable drug entry, expiration of patent rights and amounts paid pursuant to licenses of third-party patents. This royalty obligation begins upon the first commercial sale of such product in a given country and ends after the later of a defined number of years or the expiration of the last to expire licensed patent covering the product in such country. The net effect of the Servier Amendment is that the Company’s royalty rate in the United States for the first half of the first tier of net sales was increased by a low single digit percentage as compared to the Original Servier Agreement. Should Servier’s rights and obligations under the Servier-Cellectis Agreement be assigned to the Company, each tier of royalty rates in the United States to Servier would be reduced by 10%, the ex-U.S. royalties to Servier would terminate, and the Company would assume Servier’s royalty obligations to Cellectis. In the absence of any such assignment, Servier will remain responsible for making royalty payments that may be due to Cellectis under the Servier-Cellectis Agreement. The Company’s rights under the Servier Agreement with respect to CD19 Products, including cema-cel, depend in part on rights sublicensed by Servier from Cellectis. Accordingly, the purported termination of certain license agreements between LTC and Cellectis described above under “Research Collaboration and License Agreement with Cellectis” could also affect the Company’s rights with respect to CD19 Products if LTC were successful in challenging Cellectis’ rights and if the affected rights are necessary for the development, manufacture or commercialization of such products. The Company is not a party to the arbitration between LTC and Cellectis and is evaluating the potential impact, if any, on its rights under the Servier Agreement. For the three months ended March 31, 2026 and 2025, no milestones were achieved and no royalty payments were made. Research Collaboration and License Agreement with Roche (formerly Notch Therapeutics) On November 1, 2019, the Company entered into a Collaboration and License Agreement (the Notch Agreement) with Notch Therapeutics Inc. (Notch), pursuant to which Notch granted to Allogene an exclusive, worldwide, royalty-bearing, sublicensable license under certain of Notch’s intellectual property to develop, make, use, sell, import, and otherwise commercialize therapeutic gene-edited T cell and/or natural killer (NK) cell products from induced pluripotent stem cells directed at certain CAR targets for initial application in non-Hodgkin lymphoma, acute lymphoblastic leukemia and multiple myeloma. Pursuant to the Notch Agreement, the Company made certain investments in Notch’s capital stock as further described in Note 6 to the Annual Report. On January 25, 2024, the Company entered into an Amended and Restated Collaboration and License Agreement under which the Company has relinquished its exclusive rights to all original CAR targets except one, limited its option right to one additional CAR target and became entitled to a percentage of certain third party upfront and/or milestone payments (up to a stated cap) and a low, single-digit royalty on net sales if Notch out-licenses any released targets. If the option is exercised, the Company will have a minimum funding commitment for the overall development program. Following F. Hoffmann-La Roche AG’s (Roche) acquisition of Notch, in March 2025, Notch was dissolved, and Roche became Notch’s successor in interest under the Company’s agreement. In connection with such acquisition, on March 31, 2025 the Company entered into a Second Amendment to Amended and Restated Collaboration and License Agreement (Second Amended Notch Agreement) with Notch under which the definitions of certain terms were clarified, certain time periods for completing the transfer of certain technology were extended, and the scope of Allogene’s exclusive rights were clarified. Notch dissolved on September 2, 2025 and final proceeds were distributed to the Company. The Company’s total equity investment in Notch as of March 31, 2026 and December 31, 2025 was zero. For the three months ended March 31, 2026 and 2025, no milestones were achieved. Strategic Alliance with The University of Texas MD Anderson Cancer Center On October 6, 2020, the Company entered into a strategic five-year collaboration agreement with The University of Texas MD Anderson Cancer Center (MD Anderson) for the preclinical and clinical investigation of allogeneic CAR T cell product candidates. In August 2025, the Company extended the term of the agreement for an additional year. The Company and MD Anderson are collaborating on the design and conduct of preclinical and clinical studies with oversight from a joint steering committee. Under the terms of the agreement, the Company has committed up to $15.0 million of funding for the duration of the agreement, of which $6.0 million remains. Payment of this funding is contingent on mutual agreement to study orders in order for any study to be included under the alliance. The Company is committed to make further payments to MD Anderson each year upon the anniversary of the agreement effective date through the duration of the agreement term, however, if MD Anderson has sufficient funds to continue the agreed-upon research projects, the Company may defer the additional payment to a later date. These costs are expensed to research and development as MD Anderson renders the services under the strategic alliance. Collaboration costs recorded as research and development expenses were $0.1 million and $0.4 million for the three months ended March 31, 2026 and 2025, respectively. Investment in and License Agreement with Overland Therapeutics, Inc. Allogene Overland Biopharm (CY) Limited (Allogene Overland), later renamed Overland Therapeutics Inc. (Overland Therapeutics), was initially established as a joint venture by the Company and Overland Pharmaceuticals (CY) Inc. (Overland) pursuant to a Share Purchase Agreement (Share Purchase Agreement), dated December 14, 2020. Concurrently, on December 14, 2020, the Company entered into a License Agreement (License Agreement) with Allogene Overland for the purpose of developing, manufacturing and commercializing certain allogeneic CAR T cell therapies for patients in greater China, Taiwan, South Korea and Singapore (the JV Territory). Pursuant to the Share Purchase Agreement, the Company and Overland acquired Seed Preferred Shares of Allogene Overland representing 49% and 51%, respectively, of Allogene Overland’s outstanding stock. On May 24, 2024, the Company, Overland, and Allogene Overland entered into a Share Exchange Agreement (Share Exchange Agreement) pursuant to which Overland’s cell therapy business merged into Allogene Overland (the Organizational Restructuring). Under the Share Exchange Agreement, Allogene Overland acquired from Overland a 100% equity interest in Overland Pharmaceuticals (U.S.) Inc. (Overland U.S.). Overland U.S. includes certain research and development, clinical, and general and administrative staff, as well as select cell therapy assets, including its lead program, OL-101, an autologous GPRC5D-BCMA bispecific dual targeting CAR T for refractory multiple myeloma. Upon completion of the closing of the share exchange, Overland U.S. became a wholly owned subsidiary of Allogene Overland, Overland’s ownership increased to 82% and the Company’s ownership decreased to 18%. Under a separate agreement between Overland and HH BioPharma Holdings Ltd. (HBP) executed on May 24, 2024, Overland distributed all Series Seed Preferred Shares of Allogene Overland held by Overland to HBP and HBP has assumed all rights and obligations attached to such shares and all rights and obligations of Overland under the Share Exchange Agreement. In connection with the Organizational Restructuring, on May 24, 2024, the Company and Allogene Overland PRC, entered into a First Amendment to the License Agreement (the License Amendment) to amend and supplement certain provisions of the License Agreement. Under the License Amendment, the Company continues to grant Allogene Overland PRC an exclusive license to develop, manufacture, and commercialize the Licensed Products in the JV Territory, with the Company retaining exclusive rights to the Licensed Products outside the JV Territory, and the royalty obligations to the Company were amended to a flat mid single-digit royalty on net sales in the JV Territory that are no longer subject to reductions. The License Amendment also provides the Company with additional rights to terminate the License Agreement in its entirety or with respect to the relevant Overland Licensed Products if Allogene Overland PRC fails to initiate manufacturing technology transfer with respect to an Overland Licensed Product as agreed in the License Amendment, or if HBP commits a funding default or a material breach of its representations, warranties, or covenants under the Share Exchange Agreement. The License Amendment also provides that the License Agreement will terminate automatically if the Company’s ownership in Allogene Overland falls below 7.5% (other than due to the Company’s sale of the shares of Allogene Overland), unless at that time Allogene Overland PRC and the Company have mutually agreed on the manufacturing technology transfer plan for the Overland Licensed Products and Allogene Overland PRC elects to continue the license for such Overland Licensed Products with increased milestones and royalties. Under the License Amendment terms such increased milestones and royalties consist of up to $115.0 million in milestone payments for each Overland Licensed Product and tiered mid single-digit to low double-digit royalties on net sales in the JV Territory. As part of the Organizational Restructuring, Allogene Overland was renamed Overland Therapeutics Inc. (Overland Therapeutics). The Company determined that Overland Therapeutics is a variable interest entity as of March 31, 2026 and December 31, 2025. The Company does not have the power to direct the activities which most significantly affect Overland Therapeutics’ economic performance. Accordingly, the Company did not consolidate Overland Therapeutics because the Company determined that it was not the primary beneficiary. After the Organizational Restructuring, the Company has 20% voting rights of Overland Therapeutics’ board of directors. The Company concluded that it has significant influence over Overland Therapeutics and continued to account for its investment in Overland Therapeutics as an equity method investment. The Company’s total equity investment in Overland Therapeutics as of March 31, 2026 and December 31, 2025 was zero. Collaboration revenue was zero for the three months ended March 31, 2026 and 2025. As of March 31, 2026 and December 31, 2025, $4.6 million of deferred revenue was recorded in other long-term liabilities. On May 12, 2026, the Company entered into a termination agreement with Overland Therapeutics (SH) Co. Ltd. and Overland Therapeutics Inc., pursuant to which the License Agreement was terminated in its entirety. The parties also provided mutual releases of claims, and no termination payments were made in connection with the termination. In connection with the termination and related transactions, the Company surrendered a portion of its equity interests in Overland Therapeutics, resulting in a reduction of its ownership interest to approximately 3% on an as-converted and fully diluted basis. The Company is assessing the impact of these transactions on its operations and financial statements. Collaboration and License Agreement with Antion On January 5, 2022, the Company entered into an exclusive collaboration and global license agreement (Antion Collaboration and License Agreement) with Antion Biosciences SA (Antion) for Antion’s miRNA technology (miCAR), to advance multiplex gene silencing as an additional tool to develop next generation allogeneic CAR T products. In July 2023, the Company and Antion entered into an amendment to the Antion Collaboration and License Agreement. Under the terms of this amendment, Antion’s exclusivity obligation relating to the collaboration was terminated; however, Antion agreed to certain restrictions on its ability to pursue products directed against specific targets. Also, in lieu of the Company’s prior obligation to make a $3.0 million investment in Antion following the completion of certain milestones, the Company agreed to make a $2.0 million investment in Antion’s preferred stock and acquired warrants to purchase an additional $3.0 million of Antion’s preferred stock. The Company is required to make payments upon the achievement of certain development and regulatory milestones and pay royalties on certain sales pursuant to the Antion Collaboration and License Agreement as further described in Note 6 to the Annual Report. As of March 31, 2026 and December 31, 2025, the Company’s total equity investment in Antion was zero. Strategic Collaboration Agreement with Foresight Diagnostics On January 3, 2024, the Company entered into a Strategic Collaboration Agreement with Foresight Diagnostics, Inc. (Foresight Diagnostics) (the Foresight Agreement). Foresight Diagnostics was acquired by Natera, Inc. (Natera) in December 2025 and continues to operate as a standalone subsidiary. Pursuant to the Foresight Agreement, the parties have agreed to collaborate on a non-exclusive basis in the development of Foresight Diagnostics’ minimal residual disease (MRD) assay based on their PhasED-Seq Circulating Tumor DNA Platform as an in vitro diagnostic to identify the MRD+ patient population to be enrolled in the Company’s planned ALPHA3 trial of cema-cel, for treatment of large B-cell lymphoma (LBCL). Under the Foresight Agreement, the Company has agreed to use its commercially reasonable efforts to obtain regulatory approval of cema-cel, and Foresight Diagnostics has agreed to use its commercially reasonable efforts to obtain regulatory approval of its MRD assay for use as an in vitro diagnostic with cema-cel. Under the Foresight Agreement, the Company has agreed to fund approximately $26.2 million in MRD assay development costs, milestone payments for regulatory submissions and assay utilization to process clinical samples. On February 19, 2025, the Company entered into an Amended and Restated Strategic Collaboration Agreement with Foresight Diagnostics which expands its collaboration to include the development of Foresight Diagnostics’ MRD assay for use with cema-cel as part of a possible EU and/or UK clinical development program, and as part of an expansion of ALPHA3 to Canadian and Australian clinical trial sites in support of the U.S. clinical development program. In total, the Company agreed to fund approximately $37.3 million in MRD assay development costs, milestone payments for U.S., and certain international regulatory submissions and assay utilization costs to process clinical samples, all in addition to the financial commitments under the Foresight Agreement. Clinical trial milestones recorded as research and development expenses were $2.5 million and $1.3 million for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026 and December 31, 2025, $2.5 million and $1.4 million in research and development expenses, respectively, were recorded in accrued and other liabilities.

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2026
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) for interim financial information and pursuant to Form 10-Q and Article 10 of Regulation S-X of the SEC. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the Company’s opinion, all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair presentation of the results of operations and cash flows for the periods presented have been included. The condensed balance sheet as of March 31, 2026, the condensed statements of operations and comprehensive loss for the three months ended March 31, 2026 and 2025, the condensed statements of stockholders’ equity as of March 31, 2026 and 2025, the condensed statements of cash flows for the three months ended March 31, 2026 and 2025, and the financial data and other financial information disclosed in the notes to the condensed financial statements are unaudited. The results of operations for the three months ended March 31, 2026 are not necessarily indicative of the results to be expected for the year ending December 31, 2026, or for any other future annual or interim period. These condensed financial statements should be read in conjunction with the Company’s audited financial statements and related notes for the year ended December 31, 2025, included in the Company’s Annual Report on Form 10-K, filed with the SEC on March 12, 2026 (Annual Report).
Use of Estimates	Use of Estimates The preparation of condensed financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying condensed financial statements include but are not limited to the fair value of common stock, the fair value of stock options, the fair value of investments, income tax uncertainties, the CIRM (as defined below) award liability, and certain accruals. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances change. Actual results could differ from those estimates.
Significant Accounting Policies	Significant Accounting Policies There have been no significant changes to the accounting policies during the three months ended March 31, 2026, as compared to the significant accounting policies described in Note 1 of the “Notes to Financial Statements” in the Company’s audited financial statements included in its Annual Report.
Recently Adopted Accounting Pronouncements and Recent Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements There have been no new accounting pronouncements issued or effective that are expected to have a material impact on the Company’s condensed financial statements. Recent Accounting Pronouncements Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40), which requires new disclosures to disaggregate prescribed natural expenses underlying any income statement caption. ASU 2024-03 is effective for annual periods in fiscal years beginning after December 15, 2026, and interim periods thereafter. Early adoption is permitted. ASU 2024-03 applies on a prospective basis for periods beginning after the effective date. However, retrospective application to any or all prior periods presented is permitted. The Company is currently assessing the impact ASU 2024-03 will have on the financial statements and disclosures. In September 2025, the FASB issued ASU 2025-06, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which modernizes the accounting for internal-use software costs. ASU 2025-06 removes all references to prescriptive and sequential software development stages throughout Subtopic 350-40. Therefore, an entity is required to start capitalizing software costs when both of the following occur: 1) Management has authorized and committed to funding the software project and 2) It is probable that the project will be completed and the software will be used to perform the function intended. ASU 2025-06 is effective for annual periods beginning after December 15, 2027, with early adoption permitted as of the beginning of an annual period. The Company is currently in the process of evaluating the impact of this pronouncement on the financial statements and disclosures.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478671/942-235-S50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-12

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-9

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482836/275-10-55-6

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-4

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

+ Details

License and Collaboration Agreements - Cellectis (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development	$ 32,003,000	$ 50,200,000
Cellectis \| Pre-Clinical Development Milestone
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalties payments	0	0
Cellectis \| Research Collaboration And License Agreement \| Pre-Clinical Development Milestone
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development	$ 0	$ 0

Financial Instruments - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Investments, All Other Investments [Abstract]
Maximum remaining contractual maturities of available-for-sale securities (in years)	1 year
Realized losses on available-for-sale securities	$ 0.0	$ 0.0
Net unrealized loss position	0.0		$ 0.0
Accrued interest receivable from available-fore-sale investments	$ 1.3		$ 1.5
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Prepaid expenses and other current assets		Prepaid expenses and other current assets

Financial Instruments

3 Months Ended

Mar. 31, 2026

Investments, All Other Investments [Abstract]

Financial Instruments

The fair value and amortized cost of cash equivalents and available-for-sale securities by major security type as of March 31, 2026 and as of December 31, 2025 are presented in the following tables:


	March 31, 2026
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(In thousands)
Money market funds	$	25,055	$	—	$	—	$	25,055
Commercial paper	86,915		2		(178)		86,739
Corporate bonds	69,145		10		(55)		69,100
U.S. treasury securities	61,791		52		(9)		61,834
U.S. agency securities	18,909		2		(7)		18,904

Total cash equivalents and investments	$	261,815	$	66	$	(249)	$	261,632

Classified as:
Cash equivalents							$	25,055
Short-term investments							236,577
Long-term investments							—
Total cash equivalents and investments							$	261,632


	December 31, 2025
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(In thousands)
Money market funds	$	48,576	$	—	$	—	$	48,576
Commercial paper	42,696		18		(10)		42,704
Corporate bonds	53,636		69		—		53,705
U.S. treasury securities	75,990		167		—		76,157
U.S. agency securities	33,974		25		—		33,999

Total cash equivalents and investments	$	254,872	$	279	$	(10)	$	255,141

Classified as:
Cash equivalents							$	48,576
Short-term investments							198,522
Long-term investments							8,043
Total cash equivalents and investments							$	255,141

As of March 31, 2026, the remaining contractual maturities of available-for-sale securities were less than 1 year. There were no significant realized losses on available-for-sale securities for the three months ended March 31, 2026 and 2025. As of March 31, 2026, unrealized losses on available-for-sale securities are not attributed to credit risk. The Company believes that it is more likely than not that investments in an unrealized loss position will be held until maturity and all interest and principal will be received. The Company believes that an allowance for credit losses is unnecessary because the unrealized losses on certain of the Company’s available-for-sale securities are due to market factors. As of March 31, 2026 and December 31, 2025, there were no securities in a continuous net unrealized loss position for more than 12 months. To date, the Company has not recorded any impairment charges on available-for-sale securities.

The Company has made an accounting policy election not to recognize an allowance for credit losses for accrued interest receivable on available-for-sale securities. As of March 31, 2026 and December 31, 2025, the Company recognized $1.3 million and $1.5 million, respectively, of accrued interest receivable from available-for-sale securities within prepaid expenses and other current assets on the condensed balance sheets.

Condensed Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
Condensed Statements of Cash Flows - USD ($) $ in Thousands	Mar. 31, 2026	Mar. 31, 2025
Cash flows from operating activities:
Net loss	$ (42,607)	$ (59,733)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	8,270	12,175
Depreciation and amortization	2,869	3,099
Net amortization/accretion on investment securities	(885)	(1,306)
Non-cash rent expense	1,069	1,130
Changes in operating assets and liabilities:
Deposit placed in escrow	23,479	(868)
Prepaid expenses and other current assets	1,132	(623)
Other long-term assets	84	425
Accounts payable	663	(336)
Accrued and other current liabilities	(5,101)	(5,223)
Operating lease liabilities	(2,202)	(1,833)
Other long-term liabilities	316	164
Net cash used in operating activities	(12,913)	(52,929)
Cash flows from investing activities:
Purchases of property and equipment	(9)	(99)
Proceeds from maturities of investments	72,115	56,500
Purchase of investments	(101,694)	(50,225)
Net cash provided by (used in) investing activities	(29,588)	6,176
Cash flows from financing activities:
Proceeds from CIRM award (Note 5)	0	3,350
Proceeds from issuance of common stock upon exercise of stock options	4	0
Proceeds from issuance of common stock under the employee stock purchase plan	450	638
Net cash provided by financing activities	21,122	13,990
Net change in cash and cash equivalents and restricted cash	(21,379)	(32,763)
Cash and cash equivalents and restricted cash — beginning of period	61,980	85,510
Cash and cash equivalents and restricted cash — end of period	40,601	52,747
Non-cash operating activities:
Property and equipment purchases in accounts payable and accrued liabilities	146	0
Supplemental disclosure:
Cash paid for amounts included in the measurement of lease liabilities	(3,233)	(3,227)
ATM Offering
Cash flows from financing activities:
Proceeds from issuance of common stock from ATM offering, net of commissions and issuance costs	$ 20,668	$ 10,002

Condensed Statements of Stockholders’ Equity (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
ATM Offering
Issuance costs	$ 0.3	$ 0.2

Condensed Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2026	Dec. 31, 2025
Statement of Financial Position [Abstract]
Preferred stock, par or stated value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	244,816,413	229,413,523
Common stock, shares outstanding (in shares)	244,816,413	229,413,523

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Schedule of Potentially Dilutive Shares

The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share for the period presented due to their anti-dilutive effect:


	March 31,
	2026	2025
Stock options to purchase common stock	37,916,047	31,532,800
Restricted stock units outstanding (Excluding vested but unreleased shares, which are included in weighted-average common shares outstanding)	15,720,910	18,079,422
Expected shares to be purchased under Employee Stock Purchase Plan	1,409,334	1,809,262
Total	55,046,291	51,421,484

Commitments and Contingencies (Tables)

3 Months Ended

Mar. 31, 2026

Commitments and Contingencies Disclosure [Abstract]

Schedule of Lease Liabilities

The balance sheet classification of the Company’s lease liabilities was as follows (in thousands):


	March 31, 2026		December 31, 2025
Operating lease liabilities
Current portion included in accrued and other current liabilities	$	8,418	$	8,208
Lease liability, noncurrent	72,633		75,045
Total operating lease liabilities	$	81,051	$	83,253

Schedule of Lease Costs

The components of lease costs for operating leases, which were recognized in operating expenses, were as follows (in thousands):


	Three Months Ended March 31,
	2026		2025
Operating lease cost	$	2,344	$	2,525
Variable lease cost	601		556
Total lease costs	$	2,945	$	3,081

Schedule of Future Lease Payments Under Lease Liability

The undiscounted future non-cancellable lease payments under the Company’s operating leases as of March 31, 2026 were as follows:


Year ending December 31:	(In thousands)
2026 (remaining 9 months)	$	9,897
2027	13,574
2028	14,037
2029	15,437
2030	16,148
2031 and thereafter	33,597
Total undiscounted lease payments	102,690
Less: Present value adjustment	(21,639)
Total	$	81,051

Net Loss Per Share

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Net Loss Per Share

The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share for the period presented due to their anti-dilutive effect:


	March 31,
	2026	2025
Stock options to purchase common stock	37,916,047	31,532,800
Restricted stock units outstanding (Excluding vested but unreleased shares, which are included in weighted-average common shares outstanding)	15,720,910	18,079,422
Expected shares to be purchased under Employee Stock Purchase Plan	1,409,334	1,809,262
Total	55,046,291	51,421,484

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

Schedule of Stock Option Activity Under Plan

The following summarizes option activity under the 2018 Plan:


	Outstanding Options
	Number of Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contract Term	Aggregate Intrinsic Value
				(in years)	(in thousands)
Balance as of December 31, 2025	31,138,077	$	6.31	7.17	$	97
Options granted	6,995,020	1.87

Options exercised	(2,438)	$	1.94
Options forfeited	(214,612)	4.81
Balance as of March 31, 2026	37,916,047	5.50		7.48	$	9,302
Exercisable as of March 31, 2026	22,823,105	7.81		6.32	$	1,282
Vested and expected to vest as of March 31, 2026	37,916,047	$	5.50	7.48	$	9,302

Schedule of Restricted Stock Units Activity Under Plan

The following summarizes restricted stock unit activity under the 2018 Plan:


	Outstanding Restricted Stock Units
	Restricted Stock Units	Weighted- Average Grant Date Fair Value per Share		Weighted Average Remaining Vesting Life	Aggregate Intrinsic Value
				(in years)	(in thousands)
Balance as of December 31, 2025	16,528,226	$	2.99	2.39	$	22,644
Granted	3,854,459	1.87
Released	(2,482,047)	3.69
Forfeited	(1,941,228)	2.59
Balance as of March 31, 2026	15,959,410	2.66		2.81	$	38,941
Expected to vest as of March 31, 2026	15,959,410	$	2.66	2.81	$	38,941
Vested and unreleased as of March 31, 2026	238,500	$	1.29		$	582

Schedule of Stock-based Compensation Expense


	Three Months Ended March 31,
	2026		2025
Research and development	$	2,696	$	5,040
General and administrative	5,574		7,135
Total stock-based compensation	$	8,270	$	12,175

Condensed Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	ATM Offering	Common Stock	Common Stock ATM Offering	Additional Paid-in Capital	Additional Paid-in Capital ATM Offering	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2024			212,210,597
Beginning balance at Dec. 31, 2024	$ 422,179		$ 212		$ 2,241,879		$ (1,819,823)	$ (89)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares)			2,158,522
Issuance of common stock upon exercise of stock options and vesting of RSUs	0		$ 2		(2)
Issuance of common stock from ATM offering, net of commissions and offering costs (in shares)				3,842,282
Issuance of common stock from ATM offering, net of commissions and offering costs		$ 10,002		$ 4		$ 9,998
Stock-based compensation	12,175				12,175
Employee stock purchase plan (in shares)			386,861
Employee stock purchase plan	638		$ 1		637
Net loss	(59,733)						(59,733)
Net unrealized (loss) gain on available-for-sale investments	132							132
Ending balance (in shares) at Mar. 31, 2025			218,598,262
Ending balance at Mar. 31, 2025	$ 385,393		$ 219		2,264,687		(1,879,556)	43
Beginning balance (in shares) at Dec. 31, 2025	229,413,523		229,413,523
Beginning balance at Dec. 31, 2025	$ 292,542		$ 229		2,302,753		(2,010,709)	269
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares)			2,476,547
Issuance of common stock upon exercise of stock options and vesting of RSUs	4		$ 2		2
Issuance of common stock from ATM offering, net of commissions and offering costs (in shares)				12,476,533
Issuance of common stock from ATM offering, net of commissions and offering costs		$ 20,668		$ 13		$ 20,655
Stock-based compensation	8,270				8,270
Employee stock purchase plan (in shares)			449,810
Employee stock purchase plan	450		$ 1		449
Net loss	(42,607)						(42,607)
Net unrealized (loss) gain on available-for-sale investments	$ (452)							(452)
Ending balance (in shares) at Mar. 31, 2026	244,816,413		244,816,413
Ending balance at Mar. 31, 2026	$ 278,875		$ 245		$ 2,332,129		$ (2,053,316)	$ (183)

Financial Instruments - Schedule of Cash Equivalents, Restricted Cash and Investments, Classified as Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 261,815	$ 254,872
Unrealized Gains	66	279
Unrealized Losses	(249)	(10)
Fair Value	261,632	255,141
Cash equivalents	25,055	48,576
Short-term investments	236,577	198,522
Long-term investments	0	8,043
Total cash equivalents and investments	261,632	255,141
Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,055	48,576
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	25,055	48,576
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	86,915	42,696
Unrealized Gains	2	18
Unrealized Losses	(178)	(10)
Fair Value	86,739	42,704
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	69,145	53,636
Unrealized Gains	10	69
Unrealized Losses	(55)	0
Fair Value	69,100	53,705
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	61,791	75,990
Unrealized Gains	52	167
Unrealized Losses	(9)	0
Fair Value	61,834	76,157
U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	18,909	33,974
Unrealized Gains	2	25
Unrealized Losses	(7)	0
Fair Value	$ 18,904	$ 33,999

Subsequent Events (Details) - Subsequent Event $ / shares in Units, $ in Millions	Apr. 16, 2026 USD ($) $ / shares shares
April 2026 Public Offering
Subsequent Event [Line Items]
Shares sold in offering (in shares) \| shares	100,200,000
Offering price (in dollars per share) \| $ / shares	$ 2.00
Aggregate gross proceeds \| $	$ 200.4
Sale of stock, consideration received on transaction \| $	$ 187.9
Over-Allotment Option
Subsequent Event [Line Items]
Shares sold in offering (in shares) \| shares	12,700,000

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