0001737287-23-000091 | 10-Q | XBRL Viewer | Allogene Therapeutics INC

Fair Value Measurements

9 Months Ended

Sep. 30, 2023

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 September 30, 2023 and as of December 31, 2022.

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 September 30, 2023 and as of December 31, 2022 are presented in the following tables:


	September 30, 2023
	Level 1		Level 2		Level 3		Fair Value
	(In thousands)
Financial Assets:
Money market funds (1)	$	50,937	$	—	$	—	$	50,937
Corporate bonds	—		86,179		—		86,179
U.S. treasury securities	310,957		—		—		310,957
U.S. agency securities	—		41,266		—		41,266
Total financial assets	$	361,894	$	127,445	$	—	$	489,339


	December 31, 2022
	Level 1		Level 2		Level 3		Fair Value
	(In thousands)
Financial Assets:
Money market funds (1)	$	10,679	$	—	$	—	$	10,679
Commercial paper	—		4,954		—		4,954
Corporate bonds	—		153,256		—		153,256
U.S. treasury securities	318,022		—		—		318,022
U.S. agency securities	—		39,416		—		39,416
Total financial assets	$	328,701	$	197,626	$	—	$	526,327

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

+ References + Details

Commitments and Contingencies - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 3,180	$ 3,177	$ 9,536	$ 8,476
Variable lease cost	587	616	1,950	1,468
Total lease costs	$ 3,767	$ 3,793	$ 11,486	$ 9,944

Balance Sheet Components

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Components

Property and Equipment, Net

Property and Equipment consist of the following:


	September 30, 2023		December 31, 2022
	(In thousands)
Leasehold improvements	$	108,593	$	108,550
Laboratory equipment	32,940		32,601
Computer equipment and purchased software	4,664		4,533
Furniture and fixtures	4,208		4,012
Construction in progress	28		28
Total	150,433		149,724
Less: accumulated depreciation	(47,607)		(36,885)
Total property and equipment, net	$	102,826	$	112,839

Summary of Significant Accounting Policies	9 Months Ended
Summary of Significant Accounting Policies	Sep. 30, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated 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 consolidated 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 consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. All material intercompany balances and transactions have been eliminated during consolidation. The condensed consolidated balance sheet as of September 30, 2023, the condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2023 and 2022, the condensed consolidated statements of stockholders’ equity as of September 30, 2023 and 2022, the condensed consolidated statements of cash flows for the nine months ended September 30, 2023 and 2022, and the financial data and other financial information disclosed in the notes to the condensed consolidated financial statements are unaudited. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023, or for any other future annual or interim period. These condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements and related notes for the year ended December 31, 2022, included in the Company’s Annual Report on Form 10-K filed with the SEC on February 28, 2023. Use of Estimates The preparation of condensed consolidated 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 consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying condensed consolidated 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, 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 and nine months ended September 30, 2023, 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 The Company continues to monitor new accounting pronouncements issued by the FASB and does not believe any accounting pronouncements issued through the date of this report will have a material impact on the Company's condensed consolidated financial statements.

Equity Method Investments (Details) - USD ($)		1 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
Equity Method Investments (Details) - USD ($)	Nov. 01, 2019	Oct. 31, 2021	Feb. 28, 2021	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022	Dec. 14, 2020
Schedule of Equity Method Investments [Line Items]
Equity method investment				$ 5,365,000	$ 5,365,000	$ 12,817,000
Notch Therapeutics, Inc.
Schedule of Equity Method Investments [Line Items]
Payments to acquire interest in Notch	$ 5,100,000
Transaction cost	$ 100,000
Ownership percentage	25.00%
Payments for additional investment in interest		$ 1,800,000	$ 15,900,000
Equity method investment	$ 5,000,000
Equity method investment, impairment				3,000,000	3,000,000	0
Notch Therapeutics, Inc. \| Voting Interest
Schedule of Equity Method Investments [Line Items]
Ownership percentage		23.00%	20.70%
Allogene Overland
Schedule of Equity Method Investments [Line Items]
Ownership percentage							49.00%
Equity method investment				0	0	0
Carrying value				$ 0	$ 0	$ 0	$ 0

Condensed Consolidated Statements of Stockholders’ Equity (Parenthetical) - USD ($)	3 Months Ended
	Sep. 30, 2023	Jun. 30, 2023
Statement of Stockholders' Equity [Abstract]
Issuance costs	$ 50,000	$ 1,600,000

Financial Instruments

9 Months Ended

Sep. 30, 2023

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 September 30, 2023 and as of December 31, 2022 are presented in the following tables:


	September 30, 2023
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(In thousands)
Money market funds	$	50,937	$	—	$	—	$	50,937
Corporate bonds	86,734		3		(558)		86,179
U.S. treasury securities	311,637		—		(680)		310,957
U.S. agency securities	41,998		—		(732)		41,266
Total cash equivalents and investments	$	491,306	$	3	$	(1,970)	$	489,339

Classified as:
Cash equivalents							$	60,910
Short-term investments							396,259
Long-term investments							32,170
Total cash equivalents and investments							$	489,339


	December 31, 2022
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(In thousands)
Money market funds	$	10,679	$	—	$	—	$	10,679
Commercial paper	4,956		—		(2)		4,954
Corporate bonds	156,019		25		(2,788)		153,256
U.S. treasury securities	323,077		5		(5,060)		318,022
U.S. agency securities	41,078		—		(1,662)		39,416
Total cash equivalents and investments	$	535,809	$	30	$	(9,512)	$	526,327

Classified as:
Cash equivalents							$	11,760
Short-term investments							455,416
Long-term investments							59,151
Total cash equivalents and investments							$	526,327

As of September 30, 2023, the remaining contractual maturities of available-for-sale securities were less than 2 years. Realized losses on available-for-sale securities for the three and nine months ended September 30, 2023 were zero and $1.0 million, respectively. There were no significant realized losses on available-for-sale securities for the three and nine months ended September 30, 2022. As of September 30, 2023, 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 September 30, 2023 and December 31, 2022, securities with a fair value of $81.0 million and $329.4 million, respectively, were 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.

As of September 30, 2023 and December 31, 2022, the Company recognized $1.6 million and $1.8 million, respectively, of accrued interest receivable from available-for-sale securities within prepaid expenses and other current assets on the condensed consolidated balance sheets.

License and Collaboration Agreements	9 Months Ended
License and Collaboration Agreements	Sep. 30, 2023
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, including certain contracts and 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 milestone payments upon successful completion of regulatory and sales milestones on a target-by-target basis for the targets, including CD19 and B-cell maturation antigen (BCMA), covered by the Pfizer Agreement. The aggregate potential milestone payments upon successful completion of various regulatory milestones in the United States and the European Union are $30.0 million or $60.0 million, depending on the target, with aggregate potential regulatory and development milestones of up to $840.0 million, provided that the Company is not obligated to pay a milestone for regulatory approval in the European Union for an anti-CD19 allogeneic CAR T cell product, because the Company does not presently hold commercial rights in such territory. The aggregate potential milestone payments upon reaching certain annual net sales thresholds in North America, Europe, Asia, Australia and Oceania (the Territory) for a certain number of targets covered by the Pfizer Agreement are $325.0 million per target. The sales milestones in the foregoing sentence are payable on a country-by-country basis until the last to expire of any Pfizer Royalty Term, as described below, for any product in such country in the Territory. In October 2019, the Territory was expanded to all countries in the world. No milestone or royalty payments were made in the three and nine months ended September 30, 2023 or 2022. Pfizer is also eligible to receive, on a product-by-product and country-by-country basis, royalties in single-digit percentages on annual net sales for products covered by the Pfizer Agreement. The Company’s royalty obligation with respect to a given product in a given country begins upon the first sale of such product in such country and ends on the later of (i) expiration of the last claim of any applicable patent or (ii) 12 years from the first sale of such product in such country. 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. In connection with the execution of the Cellectis Agreement, on March 8, 2019, the Company and Cellectis also entered into a letter agreement (the Letter Agreement), pursuant to which the Company and Cellectis agreed to terminate the Original Cellectis Agreement. The Original Cellectis Agreement included a research collaboration to conduct discovery and pre-clinical development activities to generate CAR T cells directed at targets selected by each party, which was completed in June 2018. 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 BCMA, CD70, Claudin 18.2, DLL3 and FLT3 (the Allogene Targets), for human oncologic therapeutic, diagnostic, prophylactic and prognostic purposes. In addition, certain Cellectis intellectual property rights granted by Cellectis to the Company and to Servier pursuant to the Exclusive License and Collaboration Agreement by and between Servier and Pfizer, dated October 30, 2016, which Pfizer assigned to the Company in April 2018, will survive the termination of the Original Cellectis Agreement. Pursuant to the Cellectis Agreement, the Company granted Cellectis a non-exclusive, worldwide, royalty-free, perpetual and irrevocable license, with sublicensing rights under certain conditions, under certain of the Company's intellectual property, to make, use, sell, import and otherwise commercialize CAR T products directed at certain targets (the Cellectis Targets). The Cellectis Agreement provides for development and sales milestone payments by the Company of up to $185.0 million per product that is directed against an Allogene Target, with aggregate potential development and sales milestone payments totaling up to $2.8 billion. Cellectis is also eligible to receive tiered royalties on annual worldwide net sales of any products that are commercialized by the Company that contain or incorporate, are made using or are claimed or covered by, Cellectis intellectual property licensed to the Company under the Cellectis Agreement (the Allogene Products), at rates in the high single-digit percentages. Such royalties may be reduced, on a licensed product-by-licensed product and country-by-country basis, for generic entry and for payments due under licenses of third-party patents. Pursuant to the Cellectis Agreement, and subject to certain exceptions, the Company is required to indemnify Cellectis against all third party claims related to the development, manufacturing, commercialization or use of any Allogene Product or arising out of the Company’s material breach of the representations, warranties or covenants set forth in the Cellectis Agreement, and Cellectis is required, subject to certain exceptions, to indemnify the Company against all third party claims related to the development, manufacturing, commercialization or use of CAR T products directed at Cellectis Targets or arising out of Cellectis’s material breach of the representations, warranties or covenants set forth in the Cellectis Agreement. The royalties are payable, on a licensed-product-by-licensed-product and country-by-country basis, until the later of (i) the expiration of the last to expire of the licensed patents covering such product; (ii) the loss of regulatory exclusivity afforded such product in such country, and (iii) the tenth anniversary of the date of the first commercial sale of such product in such country; however, in no event shall such royalties be payable, with respect to a particular licensed product, past the twentieth anniversary of the first commercial sale for such product. Depending on the Cellectis Target, the Company has a right of first refusal or right of first negotiation to purchase or license from Cellectis rights to develop and commercialize products against such Cellectis Targets. Under the Cellectis Agreement, the Company has certain diligence obligations to progress the development of CAR T product candidates and to commercialize one CAR T product per Allogene Target in one major market country where the Company has received regulatory approval. If the Company materially breaches any of its diligence obligations and fails to cure within 90 days, then with respect to certain targets, such target will cease to be an Allogene Target and instead will become a Cellectis Target. Unless earlier terminated in accordance with its terms, the Cellectis Agreement will expire on a product-by-product and country-by-country basis, upon expiration of all royalty payment obligations with respect to such licensed product in such country. The Company has the right to terminate the Cellectis Agreement at will upon 60 days’ prior written notice, either in its entirety or on a target-by-target basis. Either party may terminate the Cellectis Agreement, in its entirety or on a target-by-target basis, upon 90 days’ prior written notice in the event of the other party’s uncured material breach. The Cellectis Agreement may also be terminated by the Company upon written notice at any time in the event that Cellectis becomes bankrupt or insolvent or upon written notice within 60 days of a consummation of a change of control of Cellectis. All costs the Company incurred in connection with this agreement were recognized as research and development expenses in the condensed consolidated statements of operations. For the three and nine months ended September 30, 2023 and 2022, zero costs were incurred related to the achievement of a clinical development milestone under this agreement. License and Collaboration Agreement with Servier As part of the Pfizer Agreement, Pfizer assigned to the Company an Exclusive License and Collaboration Agreement (the 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. Under the Servier Agreement, the Company has an exclusive license to develop, manufacture and commercialize UCART19, ALLO-501 and ALLO-501A in the field of anti-tumor adoptive immunotherapy in the United States, with an exclusive option to obtain the same rights for additional product candidates in the United States and, if Servier does not elect to pursue development or commercialization of those product candidates in certain markets outside of the United States pursuant to its license, outside of the United States as well. The Company is not required to make any additional payments to Servier to exercise an option. If the Company opts-in to another product candidate, Servier has the right to obtain rights to such product candidate outside the United States and to share development costs for such product candidate. Under the Servier Agreement, the Company is required to use commercially reasonable efforts to develop and obtain marketing approval in the United States in the field of anti-tumor adoptive immunotherapy for at least one product directed against CD19, and Servier is required to use commercially reasonable efforts to develop and obtain marketing approval in the European Union, and one other country in a group of specified countries outside of the European Union and the United States, in the field of anti-tumor adoptive immunotherapy for at least one allogeneic adaptive T cell product directed against a certain Company-selected target. For product candidates that the Company is co-developing with Servier, including UCART19, ALLO-501 and ALLO-501A, the Company is responsible for 60% of the specified development costs and Servier is responsible for the remaining 40% of the specified development costs under the applicable global research and development plan. Subject to certain restrictions, each party has the right to conduct activities that are specific to its territory outside the global research and development plan at such party’s sole expense. In addition, each party is solely responsible for commercialization activities in its territory at such party’s sole expense. The Company is required to make milestone payments to Servier upon successful completion of regulatory and sales milestones. The Servier Agreement provides for aggregate potential payments by the Company to Servier of up to $137.5 million upon successful completion of various regulatory milestones, and aggregate potential payments by the Company to Servier of up to $78.0 million upon successful completion of various sales milestones. Similarly, Servier is required to make milestone payments upon successful completion of regulatory and sales milestones for products directed at the Allogene-target covered by the Servier Agreement that achieves such milestones. The total potential payments that Servier is obligated to make to the Company under the Servier Agreement upon successful completion of regulatory and sales milestones are $42.0 million and €70.5 million ($74.5 million), respectively. The foregoing milestones are subject to certain adjustments if the Company obtains rights for certain products outside of the United States. Each party is also eligible to receive tiered royalties on annual net sales in countries within the paying party’s respective territory of any licensed products that are commercialized by such party that are directed at the targets licensed by such party under the Servier Agreement. The royalty rates are in a range from the low tens to the high teen percentages. Such royalties may be reduced for interchangeable drug entry, expiration of patent rights and amounts paid pursuant to licenses of third-party patents. The royalty obligation for each party with respect to a given licensed product in a given country in each party’s respective territory (the Servier Royalty Term) begins upon the first commercial sale of such product in such country and ends after a defined number of years. Unless earlier terminated in accordance with the Servier Agreement, the Servier Agreement will continue, on a licensed product-by-licensed product and country-by-country basis, until the Servier Royalty Term with respect to the sale of such licensed product in such country expires. For the three and nine months ended September 30, 2023, the Company recorded $0.1 million and $0.4 million, respectively, of net cost recoveries under the cost-sharing terms of the Servier Agreement as a reduction to research and development expenses. For the three and nine months ended September 30, 2022, the Company recorded $3.8 million and $20.4 million, respectively, of net cost recoveries. As of September 30, 2023, no amounts due from Servier were recorded in the condensed consolidated balance sheet. As of December 31, 2022, amounts due from Servier of $1.5 million were recorded in other current assets in the accompanying condensed consolidated balance sheet. On September 15, 2022, Servier sent a notice of discontinuation (Discontinuation) of its involvement in the development of all licensed products directed against CD19, including UCART19, ALLO-501 and ALLO-501A (collectively, CD19 Products), pursuant to the Servier Agreement. Servier’s Discontinuation provides the Company with the right to elect a license to the CD19 Products outside of the United States (Ex-US Option) and does not otherwise affect the Company's current exclusive license for the development and commercialization of CD19 Products in the United States. However, Servier has disputed the implications of the Discontinuation, namely whether development cost contributions continue and the timeframe during which the Company has the right to elect a license to CD19 Products outside of the United States. In December 2022, Servier sent the Company a notice for material breach due to the Company's purported refusal to allow an audit of certain manufacturing costs under the cost share arrangement. While the Company does not believe Servier has such an audit right, the Company submitted to a review of the Company's manufacturing costs of CD19 Products to recover outstanding manufacturing costs owed by Servier to the Company. In July 2023, Servier sent the Company a second notice for material breach alleging that the Company overcharged Servier based on Servier and its accounting firm’s review of costs eligible for cost-sharing under the Servier Agreement. The Company disagrees with the material breach allegations and the Company is disputing such allegations. Absent a resolution between the parties, disputed matters may be resolved in arbitration as specified in the Servier Agreement. Research Collaboration and License Agreement with 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. In addition, Notch has granted Allogene an option to add certain specified targets to its exclusive license in exchange for an agreed per-target option fee. The Notch Agreement includes a research collaboration to conduct research and pre-clinical development activities to generate engineered cells directed to Allogene’s exclusive targets, which will be conducted in accordance with an agreed research plan and budget under the oversight of a joint development committee. Allogene will reimburse Notch’s costs incurred in accordance with such plan and budget. The term of the research collaboration will expire upon the earlier of (i) the fifth anniversary of the date of the Notch Agreement, (ii) at Allogene’s election, following the joint development committee’s determination that for each exclusive target, Notch has met certain success criteria, or (iii) the joint development committee’s determination that the research collaboration cannot be reasonably pursued against any exclusive target due to technical infeasibility or safety issues. In connection with the execution of the Notch Agreement, Allogene made an upfront payment to Notch of $10.0 million in return for a license to access Notch's technology in order to conduct research pursuant to the Notch Agreement. In addition, Allogene made a $5.0 million investment in Notch’s series seed convertible preferred stock, resulting in Allogene having a 25% ownership interest in Notch’s outstanding capital stock on a fully diluted basis immediately following the investment. In connection with this investment, an Allogene representative serves on the Notch Board of Directors. In February 2021, the Company made an additional $15.9 million investment in Notch's Series A preferred stock. In October 2021, the Company made an additional $1.8 million investment in Notch's common stock. Immediately following this transaction, the Company's share in Notch was 23.0% on a voting interest basis. The Company did not have a controlling interest in Notch as of September 30, 2023, and continued to account for its investment in Notch as an equity method investment. Under the Notch Agreement, Notch will be eligible to receive up to $7.25 million upon achieving certain agreed research milestones, up to $4.0 million per exclusive target upon achieving certain pre-clinical development milestones, and up to $283.0 million per exclusive target and cell type (i.e., T cell or NK cell) upon achieving certain clinical, regulatory and commercial milestones. Notch is also entitled to receive tiered royalties in the mid to high single digit range on Allogene’s sales of licensed products, subject to certain reductions, for a term, on a country-by-country and product-by-product basis, commencing on first commercial sale of such product in such country and continuing until the latest of (i) the date upon which there is no valid claim of the licensed patents in such country of sale that covers such product, (ii) the expiration of applicable data or other regulatory exclusivity in such country of sale or (iii) a defined period from the first commercial sale of such product in such country. The terms of the Notch Agreement will continue on a product-by-product and country-by-country basis until Allogene’s payment obligations with respect to such product in such country have expired. Following such expiration, Allogene’s license with respect to such product and country shall be perpetual, irrevocable, fully paid up and royalty-free. Allogene may terminate the Collaboration Agreement in whole or on a product-by-product basis upon ninety days’ prior written notice to Notch. Either party may also terminate the Collaboration Agreement with written notice upon material breach by the other party, if such breach has not been cured within a defined period of receiving such notice, or in the event of the other party’s insolvency. For the three months ended September 30, 2023, no collaboration costs were recorded by the Company. For the nine months ended September 30, 2023, the Company recorded $1.8 million in collaboration costs as research and development expenses. For the three and nine months ended September 30, 2022, the Company recorded $1.0 million and $2.8 million, respectively, in collaboration costs as research and development expenses. For the three and nine months ended September 30, 2023, the Company recorded $3.0 million in other expenses as impairment loss on its equity method investment in Notch. No impairment loss was recorded in 2022. 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. 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. 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 made an upfront payment of $3.0 million to MD Anderson in the year ended December 31, 2020 and made an additional upfront payment of $3.0 million to MD Anderson in October 2023. The Company is obligated to make further payments to MD Anderson each year upon the anniversary of the agreement effective date through the duration of the agreement term. These costs are expensed to research and development as MD Anderson renders the services under the strategic alliance. The agreement may be terminated by either party for material breach by the other party. Individual studies may be terminated for, among other things, material breach, health and safety concerns or where the institutional review board, the review board at the clinical site with oversight of the clinical study, requests termination of any study. Where any legal or regulatory authorization is finally withdrawn or terminated, the relevant study will also terminate automatically. For the three and nine months ended September 30, 2023, the Company recorded $0.2 million and $1.2 million, respectively, in collaboration costs as research and development expenses. For the three and nine months ended September 30, 2022, the Company recorded $0.2 million and $1.1 million, respectively, in collaboration costs as research and development expenses. Joint Venture and License Agreement with Allogene Overland Biopharm (CY) Limited On December 14, 2020, the Company entered into a License Agreement with Allogene Overland Biopharm (CY) Limited (Allogene Overland), a joint venture established by the Company and Overland Pharmaceuticals (CY) Inc. (Overland), pursuant to a Share Purchase Agreement, dated December 14, 2020, 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 acquired Seed Preferred Shares in Allogene Overland representing 49% of Allogene Overland's outstanding stock as partial consideration for the License Agreement, and Overland acquired Seed Preferred Shares representing 51% of Allogene Overland's outstanding stock for $117.0 million in upfront and certain quarterly cash payments, to support operations of Allogene Overland. As of June 30, 2023, the Company and Overland are the sole equity holders in Allogene Overland. The Company received $40 million from Allogene Overland as partial consideration for the License Agreement. Pursuant to the License Agreement, the Company granted Allogene Overland an exclusive license to develop, manufacture and commercialize certain allogeneic CAR T cell candidates directed at four targets, BCMA, CD70, FLT3, and DLL3, in the JV Territory. As consideration, the Company would also be entitled to additional regulatory milestone payments of up to $40.0 million and, subject to certain conditions, tiered low-to-mid single-digit sales royalties. Subsequent to entering into the License Agreement, Allogene Overland assigned the License Agreement to a wholly-owned subsidiary, Allogene Overland BioPharm (HK) Limited. On April 1, 2022, Allogene Overland HK assigned the License Agreement to Allogene Overland Biopharm (PRC) Co., Limited. Promises that the Company concluded were distinct performance obligations in the License Agreement included: (1) the license of intellectual property and delivery of know-how, (2) the manufacturing license, related know-how and support, (3) if and when available know-how developed in future periods, and (4) participation in the joint steering committee. In order to determine the transaction price, the Company evaluated all the payments to be received during the duration of the contract. Fixed consideration exists in the form of the upfront payment. Regulatory milestones and royalties were considered variable consideration. The Company constrains the estimated variable consideration when it assesses it is probable that a significant reversal in the amount of cumulative revenue recognized may occur in future periods. Milestone fees were constrained and not included in the transaction price due to the uncertainties of research and development. The Company re-evaluates the transaction price, including the estimated variable consideration included in the transaction price and all constrained amounts, in each reporting period and as uncertain events are resolved or other changes in circumstances occur. The shares of Series Seed Preferred Stock were accounted for as part of the Company’s joint venture and equity method accounting upon formation of the joint venture, and as such, were excluded from the transaction price. The Company determined that the initial transaction price consists of the upfront payment of $40.0 million. The allocation of the transaction price is performed based on standalone selling prices, which are based on estimated amounts that the Company would charge for a performance obligation if it were sold separately. The transaction price allocated to the license of intellectual property and delivery of know-how will be recognized upon grant of license and delivery of know-how. The transaction price allocated to (i) the manufacturing license, related know-how and support services, (ii) if and when available know-how developed in future periods, and (iii) participation in the joint steering committee, will be recognized over time as the services are delivered. Funds received in advance are recorded as deferred revenue and will be recognized as the performance obligations are satisfied. The Company has determined that Allogene Overland is a variable interest entity as of September 30, 2023 and December 31, 2022, respectively. The Company does not have the power to independently direct the activities which most significantly affect Allogene Overland's economic performance. Accordingly, the Company did not consolidate Allogene Overland because the Company determined that it was not the primary beneficiary. For the three and nine months ended September 30, 2023, the Company recognized less than $0.1 million and $0.1 million, respectively, of collaboration revenue. For the three and nine months ended September 30, 2022, the Company recognized less than $0.1 million and $0.2 million, respectively, of collaboration revenue. Revenue recognized was due to delivery of the know-how performance obligations. For the three months ended September 30, 2023, no net cost recoveries were recorded by the Company. For the nine months ended September 30, 2023, the Company recorded less than $0.1 million of net cost recoveries under the terms of the license agreement as a reduction to research and development expenses. For the three and nine months ended September 30, 2022, the Company recorded $0.3 million and $0.6 million, respectively, of net cost recoveries under the terms of the license agreement as a reduction to research and development expenses. 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. Pursuant to the agreement, Antion will exclusively collaborate with the Company on oncology products for a defined period. The Company will also have exclusive worldwide rights to commercialize products incorporating Antion technology developed during the collaboration. The Antion Collaboration and License Agreement includes an exclusive research collaboration to conduct research and development of the use of Antion’s proprietary technologies to produce certain products for a defined period, which will be conducted in accordance with an agreed research plan and budget under the oversight of a joint steering committee. The Company will reimburse Antion's costs incurred in accordance with such plan and budget. In connection with the execution of the Antion Collaboration and License Agreement, the Company made an upfront payment to Antion of $3.5 million in return for a license to access Antion's technology in order to conduct research pursuant to the agreement. The upfront payment was fully recognized as research and development expense as the license had no foreseeable alternative future use. In January 2022, the Company made a $3.0 million investment in Antion's preferred stock. The Company accounts for its investment in Antion's preferred stock as an equity investment measured at cost less any impairment. In connection with this investment, a Company representative was appointed to Antion’s Board of Directors. 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 accounts for the fair value of the new investment of $1.0 million as an equity investment and the remaining $1.0 million was recorded as research and development expense. Under the Antion Collaboration and License Agreement, Antion will be eligible to receive up to $35.3 million for four products upon achievement of certain development and regulatory milestones. For each additional product, Antion will be eligible to receive $2.0 million upon achievement of a regulatory milestone. Antion is also entitled to receive a low single-digit royalty on the Company’s sales of licensed products, subject to certain reductions. For the three months ended September 30, 2023, no collaboration costs were recorded by the Company. For the nine months ended September 30, 2023, the Company recorded $1.8 million in research and development expenses related to collaboration costs. For the three and nine months ended September 30, 2022, the Company recorded $0.6 million and $4.5 million, respectively, in research and development expenses related to the upfront payment and collaboration costs. For the three and nine months ended September 30, 2023, $0.4 million in costs were incurred related to the achievement of a milestone under the Antion Collaboration and License Agreement. For the three and nine months ended September 30, 2022, no costs were incurred related to the achievement of milestone under the Antion Collaboration and License Agreement. As of September 30, 2023 and December 31, 2022, research and development expenses recorded in accrued and other liabilities were $0.4 million and $0.5 million, respectively. As of September 30, 2023 and December 31, 2022, the Company's total equity investment in Antion was $4.0 million and $3.0 million, respectively, and is recognized in other long-term assets in the condensed consolidated balance sheets.

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par 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)	168,175,221	144,438,304
Common stock, shares outstanding (in shares)	168,175,221	144,438,304

Fair Value Measurements - Financial Assets and Liabilities (Detail) - Fair Value, Measurements, Recurring - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	$ 489,339,000	$ 526,327,000
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	50,937,000	10,679,000
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets		4,954,000
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	86,179,000	153,256,000
U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	310,957,000	318,022,000
U.S. agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	41,266,000	39,416,000
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	361,894,000	328,701,000
Level 1 \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	50,937,000	10,679,000
Level 1 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets		0
Level 1 \| Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 1 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	310,957,000	318,022,000
Level 1 \| U.S. agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	127,445,000	197,626,000
Level 2 \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 2 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets		4,954,000
Level 2 \| Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	86,179,000	153,256,000
Level 2 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 2 \| U.S. agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	41,266,000	39,416,000
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 3 \| Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 3 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets		0
Level 3 \| Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 3 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 3 \| U.S. agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	$ 0	$ 0

Balance Sheet Components (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 150,433	$ 149,724
Less: accumulated depreciation	(47,607)	(36,885)
Total property and equipment, net	102,826	112,839
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	108,593	108,550
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	32,940	32,601
Computer equipment and purchased software
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	4,664	4,533
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	4,208	4,012
Construction in progress
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 28	$ 28

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net loss	$ (238,008)	$ (237,785)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	50,718	66,354
Depreciation and amortization	10,722	11,227
Net amortization/accretion on investment securities	(3,510)	2,735
Non-cash rent expense	504	2,193
Share of loss from, and impairment of, equity method investment	7,452	3,959
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	3,555	(2,811)
Other long-term assets	(421)	(3,211)
Accounts payable	(7,200)	1,930
Accrued and other current liabilities	(7,106)	(1,388)
Deferred revenue	(649)	466
Other long-term liabilities	(83)	(2,092)
Net cash used in operating activities	(184,026)	(158,423)
Cash flows from investing activities:
Purchases of property and equipment	(1,335)	(3,499)
Proceeds from sales of investments	5,623	0
Proceeds from maturities of investments	461,467	260,379
Purchase of investments	(369,927)	(200,318)
Net cash provided by investing activities	95,828	56,562
Cash flows from financing activities:
Proceeds from issuance of common stock from ATM offering, net of commissions and issuance costs	91,112	0
Proceeds from issuance of common stock upon exercise of stock options	1,932	443
Proceeds from issuance of common stock under the employee stock purchase plan	2,496	2,461
Net cash provided by financing activities	95,540	2,904
Net change in cash and cash equivalents and restricted cash	7,342	(98,957)
Cash and cash equivalents and restricted cash — beginning of period	72,196	183,606
Cash and cash equivalents and restricted cash — end of period	79,538	84,649
Non-cash investing activities:
Right-of-use asset obtained in exchange for lease liability	0	31,361
Supplemental disclosure:
Cash paid for amounts included in the measurement of lease liabilities	(9,013)	(6,605)
Cash received for amounts related to tenant improvement allowances	$ 0	$ 325

Stock-Based Compensation

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

In June 2018, the Company adopted its 2018 Equity Incentive Plan (Prior 2018 Plan). The Prior 2018 Plan provided for the Company to sell or issue common stock or restricted common stock, or to grant incentive stock options or nonqualified stock options for the purchase of common stock, to employees, members of the Company’s Board of Directors and consultants of the Company under terms and provisions established by the Company’s Board of Directors. In September 2018, the Board of Directors adopted a new amended and restated 2018 Equity Incentive Plan as a successor to and continuation of the Prior 2018 Plan, which became effective in October 2018 (the 2018 Plan), which authorized additional shares for issuance and provided for an automatic annual increase to the number of shares issuable under the 2018 Plan by an amount equal to 5% of the total number of shares of common stock outstanding on December 31st of the preceding calendar year. The term of any stock option granted under the 2018 Plan cannot exceed 10 years. The Company generally grants stock-based awards with service conditions only. Options granted typically vest over a four-year period but may be granted with different vesting terms. Restricted Stock Units granted typically vest annually over a four-year period but may be granted with different vesting terms. Options shall not have an exercise price less than 100% of the fair market value of the Company’s common stock on the grant date. If the individual possesses more than 10% of the combined voting power of all classes of stock of the Company, the exercise price shall not be less than 110% of the fair market value of a common share of stock on the date of grant. This requirement is applicable to incentive stock options only.

As of September 30, 2023, there were 6,730,462 shares reserved by the Company under the 2018 Plan for the future issuance of equity awards.

Stock Option Exchange Program

On June 21, 2022, the Company commenced an offer to exchange certain eligible options held by eligible employees of the Company for new options (the Exchange Offer). The Exchange Offer expired on July 19, 2022. Pursuant to the Exchange Offer, 199 eligible holders elected to exchange, and the Company accepted for cancellation, eligible options to purchase an aggregate of 3,666,600 shares of the Company’s common stock, representing approximately 93.5% of the total shares of common stock underlying the eligible options. On July 19, 2022, immediately following the expiration of the Exchange Offer, the Company granted new options to purchase 3,666,600 shares of common stock, pursuant to the terms of the Exchange Offer and the 2018 Plan. The exercise price of the new options granted pursuant to the Exchange Offer was $13.31 per share, which was the closing price of the common stock on the Nasdaq Global Select Market on the grant date of the new options. The new options are subject to a new three-year vesting schedule, vesting in equal annual installments over the vesting term. Each new option has a maximum term of seven years.

The exchange of stock options was treated as a modification for accounting purposes. The incremental expense of $5.2 million for the modified options was calculated using a lattice option pricing model. The incremental expense and the unamortized expense remaining on the exchanged options as of the modification date are being recognized over the new three-year service period.

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, December 31, 2022	17,569,575	$	12.90	7.73	$	6,658
Granted	9,300,276	5.13
Exercised	(782,538)	2.47			2,283
Forfeited	(4,097,851)	10.85
Balance, September 30, 2023	21,989,462	$	10.37	7.61	$	673
Exercisable, September 30, 2023	13,651,398	$	12.33	6.95	$	673
Vested and expected to vest, September 30, 2023	21,989,462	$	10.37	7.61	$	—

The aggregate intrinsic values of options outstanding, exercisable, vested and expected to vest were calculated as the difference between the exercise price of the options and the closing price of the Company’s common stock on the Nasdaq Global Select Market on September 30, 2023. For the nine months ended September 30, 2023, the estimated weighted-average grant-date fair value of employee options granted was $3.45 per share. As of September 30, 2023, there was $67.0 million of unrecognized stock-based compensation related to unvested stock options, which is expected to be recognized over a weighted-average period of 2 years, 198 days.

The fair value of employee, consultant and director stock option awards was estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions:


	Nine Months Ended September 30,
	2023	2022
Expected term in years	5.27 - 6.08	5.25 - 6.08
Expected volatility	73.18% - 73.85%	70.82% - 73.39%
Expected risk-free interest rate	3.45% - 4.30%	1.61% - 3.49%
Expected dividend	0%	0%

The fair value of the options granted under the Option Exchange program was estimated at the date of grant using a lattice option pricing model with the following assumptions: expected volatility of 73.74%, expected risk-free rate of 3.06%, expected dividends of 0% and expected exercise barrier of 2.57.

Expected term— The expected term represents the period that stock-based awards are expected to be outstanding. The expected term for option grants is determined using the simplified method. The simplified method deems the term to be the average of the time-to-vesting and the contractual life of the stock-based awards.

Expected volatility— The Company uses an average historical stock price volatility of comparable public companies within the biotechnology and pharmaceutical industry that were deemed to be representative of future stock price trends as the Company does not have sufficient trading history for its common stock. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available.

Risk-free interest rate—The risk-free interest rate is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of option.

Expected dividend—The Company has never paid dividends on its common stock and has no plans to pay dividends on its common stock. Therefore, the Company used an expected dividend yield of zero.

Expected exercise barrier— The modified options are assumed to be exercised upon vesting and when the ratio of stock market price to exercise price reaches 2.57, or expiration, whichever is earlier.

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)
Unvested December 31, 2022	5,493,406	$	16.86	1.54	$	34,554
Granted	11,215,162	4.70		2.0
Vested	(1,545,458)	18.49
Forfeited	(2,993,273)	9.35
Unvested September 30, 2023	12,169,837	$	7.29	2.14	$	38,578
Vested and expected to vest, September 30, 2023	12,169,837	$	7.29	2.14	$	38,578

As of September 30, 2023, there was $60.1 million of unrecognized stock-based compensation related to unvested restricted stock units, which is expected to be recognized over a weighted-average period of 2 years, 176 days.

For the nine months ended September 30, 2023, the Company granted 3,069,751 performance-based restricted stock units and 1,994,125 restricted stock units with a market condition to certain executive officers and other employees pursuant to the 2018 Plan. These awards are subject to the holders' continuous service to the Company through each applicable vesting event. Through September 30, 2023, 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 quarter ended September 30, 2023. The Company recognized $1.5 million in stock-based compensation expense related to the restricted units with a market condition for the nine months ended September 30, 2023.

Total stock-based compensation expense related to stock options, restricted stock units, employee stock purchase plan and vesting of the founders’ common stock was as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	6,733	$	11,016	$	22,849	$	35,068
General and administrative	8,621		10,132		27,869		31,286
Total stock-based compensation	$	15,354	$	21,148	$	50,718	$	66,354

Early Exercised Options

The Company allows certain of its employees and its directors to exercise options granted under the Prior 2018 Plan and the 2018 Plan prior to vesting. The shares related to early exercised stock options are subject to the Company’s lapsing repurchase right upon termination of employment or service on the Company’s Board of Directors at the lesser of the original purchase price or fair market value at the time of repurchase. In order to vest, the holders are required to provide continued service to the Company. The proceeds are initially recorded in accrued and other liabilities for the current portion, and other long-term liabilities for the non-current portion. The proceeds are reclassified to paid-in capital as the repurchase right lapses. In May 2021, 293,594 options were early exercised, resulting in proceeds of $5.3 million. As of September 30, 2023 and December 31, 2022, there was $1.1 million and $1.9 million, respectively, recorded in accrued and other liabilities and zero and $0.6 million, respectively, recorded in other long-term liabilities related to shares held by employees and directors that were subject to repurchase. The underlying shares are shown as outstanding in the condensed consolidated financial statements but the shares which are subject to future vesting conditions are not included in the calculation of earnings per share.

Financial Instruments - Cash Equivalents, Restricted Cash and Investments, Classified as Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 491,306	$ 535,809
Unrealized Gains	3	30
Unrealized Losses	(1,970)	(9,512)
Cash equivalents	60,910	11,760
Short-term investments	396,259	455,416
Long-term investments	32,170	59,151
Total cash equivalents and investments	489,339	526,327
Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	50,937	10,679
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	50,937	10,679
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		4,956
Unrealized Gains		0
Unrealized Losses		(2)
Fair Value		4,954
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	86,734	156,019
Unrealized Gains	3	25
Unrealized Losses	(558)	(2,788)
Fair Value	86,179	153,256
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	311,637	323,077
Unrealized Gains	0	5
Unrealized Losses	(680)	(5,060)
Fair Value	310,957	318,022
U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	41,998	41,078
Unrealized Gains	0	0
Unrealized Losses	(732)	(1,662)
Fair Value	$ 41,266	$ 39,416

License and Collaboration Agreements (Details) € in Millions					1 Months Ended					3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 05, 2022 USD ($)	Dec. 14, 2020 USD ($)	Oct. 06, 2020 USD ($)	Nov. 01, 2019 USD ($)	Oct. 31, 2023 USD ($)	Jul. 31, 2023 USD ($)	Jan. 31, 2022 USD ($)	Oct. 31, 2021 USD ($)	Feb. 28, 2021 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2023 EUR (€)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development										$ 45,977,000	$ 63,641,000	$ 188,253,000	$ 180,968,000
Equity method investment										5,365,000		5,365,000		$ 12,817,000
Collaboration revenue - related party										43,000	49,000	139,000	196,000
Payments for investments												$ 369,927,000	200,318,000
Pfizer
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty obligation period from date of first sale												12 years
University Of Texas MD Anderson Cancer Center
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaboration agreement, upfront payment															$ 3,000,000
Collaboration agreement term			5 years
Committed funding			$ 15,000,000
University Of Texas MD Anderson Cancer Center \| Subsequent Event
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaboration agreement, upfront payment					$ 3,000,000
Allogene Overland, Allogene Overland BioPharm (HK) Limited
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaboration revenue - related party										100,000	100,000	$ 100,000	200,000
Reduction to research and development expense										0	300,000	100,000	600,000
Notch Therapeutics, Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Equity method investment, impairment														0
Antion
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development						$ 1,000,000
Warrants and rights outstanding						3,000,000
Investment in equity securities						1,000,000				4,000,000		4,000,000		3,000,000
Research and development \| University Of Texas MD Anderson Cancer Center
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaboration arrangement, expense										200,000	200,000	$ 1,200,000	1,100,000
Research and development \| Notch Therapeutics, Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaborative agreement, company's right to terminate, period to provide written notice												90 days
Collaboration arrangement, expense										0	1,000,000	$ 1,800,000	2,800,000
Notch Therapeutics, Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Equity method investment				$ 5,000,000
Ownership percentage				25.00%
Payments for additional investment in interest								$ 1,800,000	$ 15,900,000
Equity method investment, impairment										3,000,000		3,000,000		0
Notch Therapeutics, Inc. \| Voting Interest
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Ownership percentage								23.00%	20.70%
Allogene Overland
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Equity method investment										0		0		0
Ownership percentage		49.00%
Allogene Overland \| Overland Pharmaceuticals Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Ownership percentage		51.00%
Research Collaboration and License Agreement \| Cellectis
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Maximum payments required per product against selected target												185,000,000
Research Collaboration and License Agreement \| Notch Therapeutics, Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payable										7,250,000		7,250,000
License and Collaboration Agreement \| Notch Therapeutics, Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaboration agreement, upfront payment				$ 10,000,000
Corporate Joint Venture \| Allogene Overland \| Overland Pharmaceuticals Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Upfront and quarterly cash payments		$ 117,000,000
Joint venture capital support payments		40,000,000
Corporate Joint Venture \| Allogene Overland \| Allogene Overland, Allogene Overland BioPharm (HK) Limited
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments		40,000,000
Collaboration agreement, upfront payment		$ 40,000,000
Antion Collaboration Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaboration agreement, upfront payment	$ 3,500,000
Collaboration arrangement, expense										0	600,000	1,800,000	4,500,000
Prior investment obligation						3,000,000
Costs incurred related to milestone achievement										400,000	0	400,000	0
Antion Collaboration Agreement \| Current Accrued and Other Liabilities
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaboration arrangement, expense												400,000		500,000
Antion Collaboration Agreement \| Preferred Stock
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Payments for investments							$ 3,000,000
Preferred stock investment payable						$ 2,000,000
Antion Collaboration Agreement, Milestone Achievement One
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payable	35,300,000
Antion Collaboration Agreement, Milestone Achievement Two
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payable	$ 2,000,000
Asset Contribution Agreement \| Pfizer
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments												325,000,000
Milestone payments										0	0	0	0
Asset Contribution Agreement \| Minimum \| Pfizer
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments												30,000,000
Asset Contribution Agreement \| Maximum \| Pfizer
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments												60,000,000
Aggregate potential regulatory and development milestones												840,000,000
Pre-Clinical Development Milestone \| Research Collaboration and License Agreement \| Cellectis
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development										0	0	0	0
Pre-Clinical Development Milestone \| Maximum \| License and Collaboration Agreement \| Notch Therapeutics, Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments												4,000,000
Clinical, Regulatory, and Commercial Milestone \| Maximum \| License and Collaboration Agreement \| Notch Therapeutics, Inc.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments												283,000,000
Development and Sales \| Maximum \| Research Collaboration and License Agreement \| Cellectis
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments												$ 2,800,000,000
Related Party \| Allogene Overland, Allogene Overland BioPharm (HK) Limited
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Net cost recoveries										0	300,000		600,000
Related Party \| License and Collaboration Agreement \| Servier
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Percentage of development costs payable by the Company												60.00%
Percentage of development cost payable by collaboration partner												40.00%
Net cost recoveries										100,000	$ 3,800,000	$ 400,000	$ 20,400,000
Due from related parties										0		0		$ 1,500,000
Related Party \| Regulatory Milestone \| License and Collaboration Agreement \| Servier
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone receivable										42,000,000		42,000,000
Related Party \| Regulatory Milestone \| Maximum \| License and Collaboration Agreement \| Servier
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments												137,500,000
Related Party \| Sales Milestone \| License and Collaboration Agreement \| Servier
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone receivable										$ 74,500,000		74,500,000				€ 70.5
Related Party \| Sales Milestone \| Maximum \| License and Collaboration Agreement \| Servier
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate potential milestone payments												$ 78,000,000
Cellectis \| Research Collaboration and License Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Collaborative agreement, breech of obligation, period to cure												90 days
Collaborative agreement, company's right to terminate, period to provide written notice												60 days
Collaborative agreement, option to terminate, period after material breech												90 days
Collaborative agreement, option to terminate, period after change in control												60 days

Cover Page - shares	9 Months Ended
Cover Page - shares	Sep. 30, 2023	Oct. 31, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
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	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		168,276,662
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity Central Index Key	0001737287
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3

Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2023

Investments, All Other Investments [Abstract]

Schedule of Fair Value and Amortized Cost


	September 30, 2023
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(In thousands)
Money market funds	$	50,937	$	—	$	—	$	50,937
Corporate bonds	86,734		3		(558)		86,179
U.S. treasury securities	311,637		—		(680)		310,957
U.S. agency securities	41,998		—		(732)		41,266
Total cash equivalents and investments	$	491,306	$	3	$	(1,970)	$	489,339

Classified as:
Cash equivalents							$	60,910
Short-term investments							396,259
Long-term investments							32,170
Total cash equivalents and investments							$	489,339


	December 31, 2022
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
	(In thousands)
Money market funds	$	10,679	$	—	$	—	$	10,679
Commercial paper	4,956		—		(2)		4,954
Corporate bonds	156,019		25		(2,788)		153,256
U.S. treasury securities	323,077		5		(5,060)		318,022
U.S. agency securities	41,078		—		(1,662)		39,416
Total cash equivalents and investments	$	535,809	$	30	$	(9,512)	$	526,327

Classified as:
Cash equivalents							$	11,760
Short-term investments							455,416
Long-term investments							59,151
Total cash equivalents and investments							$	526,327

- 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
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-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
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-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

Commitments and Contingencies - Undiscounted Future Lease Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
2023 (remaining 3 months)	$ 3,036
2024	12,447
2025	12,627
2026	12,819
2027	13,257
2028 and thereafter	77,235
Total undiscounted lease payments	131,421
Less: Present value adjustment	(34,741)
Total operating lease liabilities	$ 96,680	$ 101,124

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 30, 2023
Related Party Transactions [Abstract]
Related Party Transactions	Related Party TransactionsCollaboration Revenue In December 2020, the Company entered into a license agreement with Allogene Overland, 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 BioPharm (HK) Limited. On April 1, 2022, Allogene Overland HK assigned the license agreement to Allogene Overland Biopharm (PRC) Co., Limited. For the three and nine months ended September 30, 2023, the Company recognized less than $0.1 million and $0.1 million, respectively, of collaboration revenue under this agreement. For the three and nine months ended September 30, 2022, the Company recognized less than $0.1 million and $0.2 million, respectively, of collaboration revenue. For the three months ended September 30, 2023, no net cost recoveries were recorded by the Company. For the nine months ended September 30, 2023, the Company recorded less than $0.1 million of net cost recoveries under the terms of the license agreement as a reduction to research and development expenses. For the three and nine months ended September 30, 2022, the Company recorded $0.3 million and $0.6 million, respectively, of net cost recoveries under the terms of the license agreement as a reduction to research and development expenses. 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 Capital Advisors Inc. assumed all rights, title, interests and obligations under the sublease from Bellco Capital LLC. 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. The Company’s executive chairman, Arie Belldegrun, M.D., FACS, is a trustee of the Belldegrun Family Trust, which controls Bellco Capital Advisors Inc. The total right of use asset and associated liability recorded related to this related party lease was $0.1 million and $0.2 million at September 30, 2023 and December 31, 2022, respectively. In February 2023, the Company subleased an additional 2,030 square feet of office space in Los Angeles, California, from Bellco. The sublease term is 115 months, subject to certain early termination rights. The sublease is expected to commence January 1, 2024. The Company paid approximately $0.2 million towards the monthly base rent due for the first month of the sublease term and its share of the security deposit. The total estimated amount of base rent is $2.9 million, subject to rent abatement. The Company also expects to contribute to certain tenant improvements to the space totaling to its share of the total tenant contribution. Consulting Agreements In June 2018, the Company entered into a services agreement with Two River Consulting, LLC (Two River), a firm affiliated with the Company’s President and Chief Executive Officer, the Company’s Executive Chair of the board of directors, and a director of the Company to provide various managerial, clinical development, administrative, accounting and financial services to the Company. The costs incurred for services provided under this agreement were $0.1 million and $0.3 million for the three and nine months ended September 30, 2023, respectively. The costs incurred for services provided under this agreement were $0.1 million and $0.6 million for the three and nine months ended September 30, 2022, respectively. 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. 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 $0.3 million and $0.7 million for the three and nine months ended September 30, 2023, respectively. The costs incurred for services provided and out-of-pocket expenses incurred under this consulting agreement were $0.2 million and $0.6 million for the three and nine months ended September 30, 2022, respectively.

- Definition

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

+ References

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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

+ Details

Net Loss Per Share

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Net Loss Per Share

Net Loss Per ShareThe 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:


	September 30,
	2023	2022
Stock options to purchase common stock	21,989,462	18,122,447
Restricted stock units subject to vesting	12,169,837	6,108,670
Expected shares to be purchased under Employee Stock Purchase Plan	1,289,434	750,317
Early exercised stock options subject to future vesting	58,360	162,532
Total	35,507,093	25,143,966

Financial Instruments - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Financial Instruments - Narrative (Details) - USD ($)	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Investments, All Other Investments [Abstract]
Maximum remaining contractual maturities of available-for-sale securities (in years)	2 years		2 years
Realized losses on available-for-sale securities	$ 0	$ 0	$ 1,000,000	$ 0
Net unrealized loss position	81,000,000		81,000,000		$ 329,400,000
Accrued interest receivable from available-fore-sale investments	$ 1,600,000		$ 1,600,000		$ 1,800,000

Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2023

Commitments and Contingencies Disclosure [Abstract]

Schedule of Lease Liabilities

The balance sheet classification of our lease liabilities were as follows (in thousands):


	September 30, 2023		December 31, 2022
Operating lease liabilities
Current portion included in accrued and other current liabilities	$	6,578	$	6,002
Long-term portion of lease liabilities	90,102		95,122
Total operating lease liabilities	$	96,680	$	101,124

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 September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Operating lease cost	$	3,180	$	3,177	$	9,536	$	8,476
Variable lease cost	587		616		1,950		1,468
Total lease costs	$	3,767	$	3,793	$	11,486	$	9,944

Summary of Future Lease Payments Under Lease Liability

The undiscounted future non-cancellable lease payments under the Company's operating leases as of September 30, 2023 were as follows:


Year ending December 31:	(In thousands)
2023 (remaining 3 months)	$	3,036
2024	12,447
2025	12,627
2026	12,819
2027	13,257
2028 and thereafter	77,235
Total undiscounted lease payments	131,421
Less: Present value adjustment	(34,741)
Total	$	96,680

Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Summary 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, December 31, 2022	17,569,575	$	12.90	7.73	$	6,658
Granted	9,300,276	5.13
Exercised	(782,538)	2.47			2,283
Forfeited	(4,097,851)	10.85
Balance, September 30, 2023	21,989,462	$	10.37	7.61	$	673
Exercisable, September 30, 2023	13,651,398	$	12.33	6.95	$	673
Vested and expected to vest, September 30, 2023	21,989,462	$	10.37	7.61	$	—

Schedule Stock Option Valuation Assumptions

The fair value of employee, consultant and director stock option awards was estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions:


	Nine Months Ended September 30,
	2023	2022
Expected term in years	5.27 - 6.08	5.25 - 6.08
Expected volatility	73.18% - 73.85%	70.82% - 73.39%
Expected risk-free interest rate	3.45% - 4.30%	1.61% - 3.49%
Expected dividend	0%	0%

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)
Unvested December 31, 2022	5,493,406	$	16.86	1.54	$	34,554
Granted	11,215,162	4.70		2.0
Vested	(1,545,458)	18.49
Forfeited	(2,993,273)	9.35
Unvested September 30, 2023	12,169,837	$	7.29	2.14	$	38,578
Vested and expected to vest, September 30, 2023	12,169,837	$	7.29	2.14	$	38,578

Schedule of Stock-Based Compensation Expense

Total stock-based compensation expense related to stock options, restricted stock units, employee stock purchase plan and vesting of the founders’ common stock was as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	6,733	$	11,016	$	22,849	$	35,068
General and administrative	8,621		10,132		27,869		31,286
Total stock-based compensation	$	15,354	$	21,148	$	50,718	$	66,354

Equity Method Investments	9 Months Ended
Equity Method Investments	Sep. 30, 2023
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Equity Method Investments Notch Therapeutics In conjunction with the execution of the Notch Agreement (see Note 6), the Company also entered into a Share Purchase Agreement with the Company acquiring shares of Notch’s Series Seed convertible preferred stock for a total investment cost of $5.1 million which includes transaction costs of $0.1 million, resulting in a 25% ownership interest in Notch. In February 2021, the Company made a $15.9 million investment in Notch's Series A preferred stock. Immediately following this transaction, the Company's share in Notch was 20.7% on a voting interest basis. In October 2021, the Company made an additional $1.8 million investment in Notch's common stock. Immediately following this transaction, the Company's share in Notch was 23.0% on a voting interest basis. The Company’s total equity investment in Notch as of September 30, 2023 and December 31, 2022 was $5.4 million and $12.8 million, respectively, and the Company accounted for the investment using the equity method of accounting. During the three and nine months ended September 30, 2023 and 2022, the Company recognized its share of Notch's net loss under the other expenses caption within the condensed consolidated statements of operations. During the three and nine months ended September 30, 2023, the Company recognized $3.0 million of impairment loss under the other expenses caption within the condensed consolidated statements of operations. No impairment loss was recorded in 2022. Allogene Overland Biopharm (CY) Limited In conjunction with the execution of the License Agreement with Allogene Overland (see Note 6), the Company also entered into a Share Purchase Agreement and Shareholders' Agreement with the joint venture company acquiring shares of Allogene Overland’s Seed Preferred Shares representing a 49% ownership interest in exchange for entering into a License Agreement which had a carrying value of zero. The Company accounts for its investment in Allogene Overland as an equity method investment at carrying value. The Company's total equity investment in Allogene Overland was zero as of September 30, 2023 and December 31, 2022. The Company’s equity investment in Allogene Overland as of September 30, 2023 and December 31, 2022 had a zero carryover basis. Therefore, the Company did not account for its share of losses incurred by Allogene Overland. See Note 6 for further details.

Description of Business	9 Months Ended
Description of Business	Sep. 30, 2023
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. The Company is developing a pipeline of off-the-shelf T cell product candidates that are designed to target and kill cancer cells. Public Offerings In November 2019, the Company entered into a sales agreement with Cowen and Company, LLC (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 Cowen in at-the-market (ATM) offerings. The aggregate compensation payable to Cowen as the Company's sales agent equals up to 3.0% of the gross sales price of the shares sold through Cowen pursuant to the sales agreement. During the nine months ended September 30, 2023, the Company sold an aggregate of 20,894,565 shares of common stock in ATM offerings resulting in net proceeds of $91.1 million. 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 and cash equivalents and investments of $497.7 million as of September 30, 2023. Since inception through September 30, 2023, the Company has incurred cumulative net losses of $1.5 billion. 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 intends to raise additional capital through the issuance of equity securities, debt financings or other sources in order to further implement its business plan. However, if such financing is not available at adequate levels, the Company will need to reevaluate its operating plan and may be required to delay the development of its product candidates. The Company expects that its cash and cash equivalents and investments will be sufficient to fund its operations for at least the next 12 months from the date the accompanying unaudited condensed consolidated financial statements are filed with the Securities and Exchange Commission (SEC).

Stock-Based Compensation - Restricted Stock Units Activity (Details) - Restricted Stock Unit - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Restricted Stock Units
Restricted stock units, unvested, beginning balance (in shares)	5,493,406
Restricted stock units, granted (in shares)	11,215,162
Restricted stock units, vested (in shares)	(1,545,458)
Restricted stock units, forfeited (in shares)	(2,993,273)
Restricted stock units, unvested, ending balance (in shares)	12,169,837	5,493,406
Restricted stock units, vested and expected to vest (in shares)	12,169,837
Weighted- Average Grant Date Fair Value per Share
Weighted-average fair value at date of grant per share, beginning balance (in dollars per share)	$ 16.86
Weighted-average fair value at date of grant per share, granted (in dollars per share)	4.70
Weighted-average fair value at date of grant per share, vested (in dollars per share)	18.49
Weighted-average fair value at date of grant per share, forfeited (in dollars per share)	9.35
Weighted-average fair value at date of grant per share, ending balance (in dollars per share)	7.29	$ 16.86
Weighted-average fair value at date of grant per share, vested and expected to vest (in dollars per share)	$ 7.29
Weighted average remaining vesting life, unvested (in years)	2 years 1 month 20 days	1 year 6 months 14 days
Weighted average remaining vesting life, granted (in years)	2 years
Weighted average remaining vesting life, vested and expected to vest (in years)	2 years 1 month 20 days
Aggregate intrinsic value, unvested	$ 38,578	$ 34,554
Aggregate intrinsic value, vested and expected to vest	$ 38,578

Stock-Based Compensation - Narrative (Details)		1 Months Ended	3 Months Ended		9 Months Ended
Stock-Based Compensation - Narrative (Details)	Jul. 19, 2022 USD ($) $ / shares shares	May 31, 2021 USD ($) shares	Sep. 30, 2023 USD ($) $ / shares shares	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) $ / shares shares	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Jun. 21, 2022 employee shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares as percentage of common shares outstanding					5.00%
Number of shares reserved for future issuance (in shares) \| shares			6,730,462		6,730,462
Plan modification, incremental cost	$ 5,200,000
Expected dividend rate					0.00%
Expected exercise barrier (in dollars per share) \| $ / shares			$ 2.57		$ 2.57
Total stock-based compensation			$ 15,354,000	$ 21,148,000	$ 50,718,000	$ 66,354,000
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares) \| shares		293,594
Accrued and other liabilities, related to shares held by employees and directors that were subject to repurchase			1,100,000		1,100,000		$ 1,900,000
Other long term liabilities, related to shares held by employees and directors that were subject to repurchase			0		$ 0		$ 600,000
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					4 years
Restricted Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					4 years
Unrecognized stock based compensation expense			60,100,000		$ 60,100,000
Unrecognized stock based compensation expense, weighted average recognition period (in years)					2 years 176 days
Restricted stock units, granted (in shares) \| shares					11,215,162
Stock options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Exchange offer, number of employees \| employee								199
Exchange offer, number of options accepted for cancellation (in shares) \| shares								3,666,600
Exchange offer, number of options accepted for cancellation as a percent of shares outstanding								0.935
Number of options, options granted (in shares) \| shares	3,666,600
Weighted average exercise price (in dollars per share) \| $ / shares	$ 13.31
Expiration period	7 years
Grants in period, weighted average grant date fair value (in dollars per share) \| $ / shares					$ 3,450,000
Unrecognized stock based compensation expense			$ 67,000,000		$ 67,000,000
Unrecognized stock based compensation expense, weighted average recognition period (in years)					2 years 198 days
Expected volatility					73.74%
Expected risk-free rate					3.06%
Expected dividend rate					0.00%
Expected exercise barrier (in dollars per share) \| $ / shares			$ 2.57		$ 2.57
Early exercised stock options subject to future vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from stock options exercised		$ 5,300,000
Performance-Based Restricted Stock Units \| Certain Executive Officers And Other Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, granted (in shares) \| shares					3,069,751
Total stock-based compensation			$ 0
Restricted Stock Units (RSUs) With Market Condition \| Certain Executive Officers And Other Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, granted (in shares) \| shares					1,994,125
Total stock-based compensation					$ 1,500,000
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grant period					10 years
Option exercise price as percentage of fair value of common stock on grate date					100.00%
Option exercise price as a percentage of fair value of common stock on grant date					110.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Combined voting power by individual (as a percent)					10.00%

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 69,246	$ 61,904
Short-term investments	396,259	455,416
Prepaid expenses and other current assets	7,949	11,504
Total current assets	473,454	528,824
Long-term investments	32,170	59,151
Operating lease right-of-use asset	78,643	83,592
Property and equipment, net	102,826	112,839
Restricted cash	10,292	10,292
Other long-term assets	9,576	9,564
Equity method investment	5,365	12,817
Total assets	712,326	817,079
Current liabilities:
Accounts payable	6,205	13,890
Accrued and other current liabilities	31,195	39,743
Deferred revenue	236	885
Total current liabilities	37,636	54,518
Lease liability, non-current	90,102	95,122
Other long-term liabilities	1,486	1,569
Total liabilities	129,224	151,209
Commitments and Contingencies (Notes 6 and 7)
Stockholders’ equity:
Preferred stock, $0.001 par value: 10,000,000 shares authorized as of September 30, 2023 and December 31, 2022; no shares were issued and outstanding as of September 30, 2023 and December 31, 2022	0	0
Common stock, $0.001 par value: 400,000,000 shares authorized as of September 30, 2023 and December 31, 2022; 168,175,221 and 144,438,304 shares issued and outstanding as of September 30, 2023 and December 31, 2022, respectively	168	144
Additional paid-in capital	2,059,333	1,911,632
Accumulated deficit	(1,473,988)	(1,235,980)
Accumulated other comprehensive loss	(2,411)	(9,926)
Total stockholders’ equity	583,102	665,870
Total liabilities and stockholders’ equity	$ 712,326	$ 817,079

Stock-Based Compensation - Valuation Assumptions (Details)	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend	0.00%
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, minimum	73.18%	70.82%
Expected volatility, maximum	73.85%	73.39%
Expected risk-free interest rate, minimum	3.45%	1.61%
Expected risk-free interest rate, maximum	4.30%	3.49%
Expected dividend	0.00%	0.00%
2018 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term in years	5 years 3 months 7 days	5 years 3 months
2018 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term in years	6 years 29 days	6 years 29 days

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated 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 consolidated 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 consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. All material intercompany balances and transactions have been eliminated during consolidation. The condensed consolidated balance sheet as of September 30, 2023, the condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2023 and 2022, the condensed consolidated statements of stockholders’ equity as of September 30, 2023 and 2022, the condensed consolidated statements of cash flows for the nine months ended September 30, 2023 and 2022, and the financial data and other financial information disclosed in the notes to the condensed consolidated financial statements are unaudited. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023, or for any other future annual or interim period. These condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements and related notes for the year ended December 31, 2022, included in the Company’s Annual Report on Form 10-K filed with the SEC on February 28, 2023.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying condensed consolidated 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, 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 and nine months ended September 30, 2023, 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 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 The Company continues to monitor new accounting pronouncements issued by the FASB and does not believe any accounting pronouncements issued through the date of this report will have a material impact on the Company's condensed consolidated financial statements.

Condensed Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2021		142,623,065
Beginning balance at Dec. 31, 2021	$ 916,406	$ 142	$ 1,822,179	$ (903,348)	$ (2,567)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares)		715,961
Issuance of common stock upon exercise of stock options and vesting of RSUs	283	$ 1	282
Vesting of early exercised common stock	1,228		1,228
Stock-based compensation	22,315		22,315
Employee stock purchase plan (in shares)		230,876
Employee stock purchase plan	1,530		1,530
Net loss	(79,850)			(79,850)
Net unrealized gain (loss) on available-for-sale investments	(6,682)				(6,682)
Ending balance (in shares) at Mar. 31, 2022		143,569,902
Ending balance at Mar. 31, 2022	855,230	$ 143	1,847,534	(983,198)	(9,249)
Beginning balance (in shares) at Dec. 31, 2021		142,623,065
Beginning balance at Dec. 31, 2021	916,406	$ 142	1,822,179	(903,348)	(2,567)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(237,785)
Net unrealized gain (loss) on available-for-sale investments	(10,391)
Ending balance (in shares) at Sep. 30, 2022		144,031,588
Ending balance at Sep. 30, 2022	739,961	$ 144	1,893,908	(1,141,133)	(12,958)
Beginning balance (in shares) at Mar. 31, 2022		143,569,902
Beginning balance at Mar. 31, 2022	855,230	$ 143	1,847,534	(983,198)	(9,249)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares)		153,269
Issuance of common stock upon exercise of stock options and vesting of RSUs	25	$ 1	24
Vesting of early exercised common stock	813		813
Stock-based compensation	22,891		22,891
Net loss	(74,787)			(74,787)
Net unrealized gain (loss) on available-for-sale investments	(2,223)				(2,223)
Ending balance (in shares) at Jun. 30, 2022		143,723,171
Ending balance at Jun. 30, 2022	801,949	$ 144	1,871,262	(1,057,985)	(11,472)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares)		177,678
Issuance of common stock upon exercise of stock options and vesting of RSUs	135		135
Vesting of early exercised common stock	432		432
Stock-based compensation	21,148		21,148
Employee stock purchase plan (in shares)		130,739
Employee stock purchase plan	931		931
Net loss	(83,148)			(83,148)
Net unrealized gain (loss) on available-for-sale investments	(1,486)				(1,486)
Ending balance (in shares) at Sep. 30, 2022		144,031,588
Ending balance at Sep. 30, 2022	$ 739,961	$ 144	1,893,908	(1,141,133)	(12,958)
Beginning balance (in shares) at Dec. 31, 2022	144,438,304	144,438,304
Beginning balance at Dec. 31, 2022	$ 665,870	$ 144	1,911,632	(1,235,980)	(9,926)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares)		942,276
Issuance of common stock upon exercise of stock options and vesting of RSUs	0	$ 1	(1)
Vesting of early exercised common stock	603		603
Stock-based compensation	18,770		18,770
Employee stock purchase plan (in shares)		359,753
Employee stock purchase plan	1,731	$ 1	1,730
Net loss	(98,704)			(98,704)
Net unrealized gain (loss) on available-for-sale investments	3,992				3,992
Ending balance (in shares) at Mar. 31, 2023		145,740,333
Ending balance at Mar. 31, 2023	$ 592,262	$ 146	1,932,734	(1,334,684)	(5,934)
Beginning balance (in shares) at Dec. 31, 2022	144,438,304	144,438,304
Beginning balance at Dec. 31, 2022	$ 665,870	$ 144	1,911,632	(1,235,980)	(9,926)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(238,008)
Net unrealized gain (loss) on available-for-sale investments	$ 7,515
Ending balance (in shares) at Sep. 30, 2023	168,175,221	168,175,221
Ending balance at Sep. 30, 2023	$ 583,102	$ 168	2,059,333	(1,473,988)	(2,411)
Beginning balance (in shares) at Mar. 31, 2023		145,740,333
Beginning balance at Mar. 31, 2023	592,262	$ 146	1,932,734	(1,334,684)	(5,934)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from ATM offering, net of commissions and offering costs (in shares)		20,288,330
Issuance of common stock from ATM offering, net of commissions and offering costs	87,918	$ 20	87,898
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares)		1,105,001
Issuance of common stock upon exercise of stock options and vesting of RSUs	1,606	$ 1	1,605
Vesting of early exercised common stock	432		432
Stock-based compensation	16,594		16,594
Net loss	(77,989)			(77,989)
Net unrealized gain (loss) on available-for-sale investments	2,083				2,083
Ending balance (in shares) at Jun. 30, 2023		167,133,664
Ending balance at Jun. 30, 2023	622,906	$ 167	2,039,263	(1,412,673)	(3,851)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from ATM offering, net of commissions and offering costs (in shares)		606,235
Issuance of common stock from ATM offering, net of commissions and offering costs	3,194	$ 1	3,193
Issuance of common stock upon exercise of stock options and vesting of RSUs (in shares)		204,116
Issuance of common stock upon exercise of stock options and vesting of RSUs	326	$ 0	326
Vesting of early exercised common stock	432		432
Stock-based compensation	15,354		15,354
Employee stock purchase plan (in shares)		231,206
Employee stock purchase plan	765	$ 0	765
Net loss	(61,315)			(61,315)
Net unrealized gain (loss) on available-for-sale investments	$ 1,440				1,440
Ending balance (in shares) at Sep. 30, 2023	168,175,221	168,175,221
Ending balance at Sep. 30, 2023	$ 583,102	$ 168	$ 2,059,333	$ (1,473,988)	$ (2,411)

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsNone.

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2023

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


	September 30, 2023
	Level 1		Level 2		Level 3		Fair Value
	(In thousands)
Financial Assets:
Money market funds (1)	$	50,937	$	—	$	—	$	50,937
Corporate bonds	—		86,179		—		86,179
U.S. treasury securities	310,957		—		—		310,957
U.S. agency securities	—		41,266		—		41,266
Total financial assets	$	361,894	$	127,445	$	—	$	489,339


	December 31, 2022
	Level 1		Level 2		Level 3		Fair Value
	(In thousands)
Financial Assets:
Money market funds (1)	$	10,679	$	—	$	—	$	10,679
Commercial paper	—		4,954		—		4,954
Corporate bonds	—		153,256		—		153,256
U.S. treasury securities	318,022		—		—		318,022
U.S. agency securities	—		39,416		—		39,416
Total financial assets	$	328,701	$	197,626	$	—	$	526,327

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

Fair Value Measurements - Narrative (Detail) - Fair Value, Measurements, Recurring - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	$ 489,339,000	$ 526,327,000
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Financial liabilities	$ 0	$ 0

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income TaxesThe Company has a history of losses and expects to record a loss in 2023. The Company continues to maintain a full valuation allowance against its net deferred tax assets.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: 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 2: 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 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: 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 5: 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 6: 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//1943274/2147482526/740-270-50-1

Reference 7: 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 8: 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 9: 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 10: 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

Net Loss Per Share (Tables)

9 Months Ended

Sep. 30, 2023

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:


	September 30,
	2023	2022
Stock options to purchase common stock	21,989,462	18,122,447
Restricted stock units subject to vesting	12,169,837	6,108,670
Expected shares to be purchased under Employee Stock Purchase Plan	1,289,434	750,317
Early exercised stock options subject to future vesting	58,360	162,532
Total	35,507,093	25,143,966

Related Party Transactions (Details)	1 Months Ended				3 Months Ended		9 Months Ended
Related Party Transactions (Details)	Feb. 28, 2023 USD ($) ft²	Jul. 31, 2022 ft²	Dec. 31, 2018 ft²	Aug. 31, 2018	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Related Party Transaction [Line Items]
Collaboration revenue, related party (less than)					$ 43,000	$ 49,000	$ 139,000	$ 196,000
Operating lease right-of-use asset					78,643,000		78,643,000		$ 83,592,000
Operating lease liability					96,680,000		96,680,000		101,124,000
Base rent and security deposit, payment	$ 200,000
Total estimated base rent	$ 2,900,000
Allogene Overland, Allogene Overland BioPharm (HK) Limited
Related Party Transaction [Line Items]
Collaboration revenue, related party (less than)					100,000	100,000	100,000	200,000
Reduction to research and development expense					0	300,000	100,000	600,000
Related Party \| Allogene Overland, Allogene Overland BioPharm (HK) Limited
Related Party Transaction [Line Items]
Net cost recoveries					0	300,000		600,000
Related Party \| Sublease Agreement \| Bellco
Related Party Transaction [Line Items]
Area of office space (in square feet) \| ft²	2,030	737	1,293
Sublease, term of contract (in years)	115 months		3 years
Operating lease right-of-use asset					100,000		100,000		200,000
Operating lease liability					100,000		100,000		$ 200,000
Related Party \| Consulting Agreements \| Bellco
Related Party Transaction [Line Items]
Cost of revenue					300,000	200,000	700,000	600,000
Related Party \| Consulting Agreements \| Two River
Related Party Transaction [Line Items]
Cost of revenue					$ 100,000	$ 100,000	300,000	$ 600,000
Related Party \| Consulting Agreements \| Payments Commencing January 2022 \| Bellco
Related Party Transaction [Line Items]
Monthly payments in arrears							$ 40,217
Related Party \| Consulting Agreements \| Maximum \| Bellco
Related Party Transaction [Line Items]
Related party transaction compensation percentage				60.00%

Description of Business (Details) - USD ($) $ in Thousands	9 Months Ended
Description of Business (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Nov. 30, 2019
Subsidiary, Sale of Stock [Line Items]
Stock issuance, maximum compensation due to third party (as a percent of stock sales)			3.00%
Cash and cash equivalents and marketable securities	$ 497,700
Accumulated deficit	$ (1,473,988)	$ (1,235,980)
ATM offering
Subsidiary, Sale of Stock [Line Items]
Shares sold in transaction (in shares)	20,894,565
Gross proceeds from sale of stock	$ 91,100

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Commitments and Contingencies - Lease Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
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	$ 6,578	$ 6,002
Long-term portion of lease liabilities	90,102	95,122
Total operating lease liabilities	$ 96,680	$ 101,124

Stock-Based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	$ 15,354	$ 21,148	$ 50,718	$ 66,354
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	6,733	11,016	22,849	35,068
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	$ 8,621	$ 10,132	$ 27,869	$ 31,286

Balance Sheet Components (Tables)

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Property and Equipment

Property and Equipment consist of the following:


	September 30, 2023		December 31, 2022
	(In thousands)
Leasehold improvements	$	108,593	$	108,550
Laboratory equipment	32,940		32,601
Computer equipment and purchased software	4,664		4,533
Furniture and fixtures	4,208		4,012
Construction in progress	28		28
Total	150,433		149,724
Less: accumulated depreciation	(47,607)		(36,885)
Total property and equipment, net	$	102,826	$	112,839

Net Loss Per Share (Details) - shares	9 Months Ended
Net Loss Per Share (Details) - shares	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of diluted net loss per share (in shares)	35,507,093	25,143,966
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)	21,989,462	18,122,447
Restricted stock units subject to vesting
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of diluted net loss per share (in shares)	12,169,837	6,108,670
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)	1,289,434	750,317
Early exercised stock options subject to future vesting
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of diluted net loss per share (in shares)	58,360	162,532

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenues
Collaboration revenue - related party	$ 43	$ 49	$ 139	$ 196
Operating expenses:
Research and development	45,977	63,641	188,253	180,968
General and administrative	17,041	18,897	54,449	58,303
Total operating expenses	63,018	82,538	242,702	239,271
Loss from operations	(62,975)	(82,489)	(242,563)	(239,075)
Other income (expense), net:
Interest and other income, net	6,205	1,002	12,042	1,809
Other expenses	(4,545)	(1,661)	(7,487)	(519)
Total other income (expense), net	1,660	(659)	4,555	1,290
Net loss	(61,315)	(83,148)	(238,008)	(237,785)
Other comprehensive loss:
Net unrealized gain (loss) on available-for-sale investments	1,440	(1,486)	7,515	(10,391)
Net comprehensive loss	$ (59,875)	$ (84,634)	$ (230,493)	$ (248,176)
Net loss per share, basic (in dollars per share)	$ (0.37)	$ (0.58)	$ (1.55)	$ (1.67)
Net loss per share, diluted (in dollars per share)	$ (0.37)	$ (0.58)	$ (1.55)	$ (1.67)
Weighted-average number of shares used in computing net loss per share, basic (in shares)	167,649,010	143,661,721	153,087,449	142,809,469
Weighted-average number of shares used in computing net loss per share, diluted (in shares)	167,649,010	143,661,721	153,087,449	142,809,469

Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	9 Months Ended	12 Months Ended
	May 31, 2021	Sep. 30, 2023	Dec. 31, 2022
Number of Options
Number of options, options exercised (in shares)	(293,594)
2018 Plan
Number of Options
Number of options, beginning balance (in shares)		17,569,575
Number of options, options granted (in shares)		9,300,276
Number of options, options exercised (in shares)		(782,538)
Number of options, options forfeited (in shares)		(4,097,851)
Number of options, ending balance (in shares)		21,989,462	17,569,575
Number of options, exercisable (in shares)		13,651,398
Number of options, vested and expected to vest (in shares)		21,989,462
Weighted- Average Exercise Price
Weighted-average exercise price, beginning balance (in dollars per share)		$ 12.90
Weighted-average exercise price, options granted (in dollars per share)		5.13
Weighted-average exercise price, options exercised (in dollars per share)		2.47
Weighted-average exercise price, options forfeited (in dollars per share)		10.85
Weighted-average exercise price, ending balance (in dollars per share)		10.37	$ 12.90
Weighted-average exercise price, exercisable (in dollars per share)		12.33
Weighted-average exercise price, vested and expected to vest (in dollars per share)		$ 10.37
Weighted-average remaining contract term, outstanding (in years)		7 years 7 months 9 days	7 years 8 months 23 days
Weighted-average remaining contract term, exercisable (in years)		6 years 11 months 12 days
Weighted-average remaining contract term, vested and expected to vest (in years)		7 years 7 months 9 days
Aggregate intrinsic value, balance		$ 673	$ 6,658
Aggregate intrinsic value, exercised		2,283
Aggregate intrinsic value, exercisable		673
Aggregate intrinsic value, vested and expected to vest		$ 0

Commitments and Contingencies

9 Months Ended

Sep. 30, 2023

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. The lease term was 127 months beginning August 2018 through February 2029 with an option to extend the term for seven years which was not reasonably assured of exercise. The Company has made certain tenant improvements, including the addition of laboratory space, and has received $5.0 million of tenant improvement allowances through December 31, 2020. The rent payments began on March 1, 2019 after an abatement period. 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 and is for a period of 120 months. The rent payments for the expansion premises began in August 2022 after an abatement period. The lease term for the existing premises was also extended and the lease 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 was 124 months beginning November 2018 through February 2029, with an option to extend the term for another seven years which was not reasonably assured of exercise. The Company has made certain tenant improvements, including the upgrading of current office and laboratory space with a lease incentive allowance of $0.8 million. Rent payments began in November 2018. In December 2021, the Company amended its lease agreement to extend the term of the lease to be co-terminus with the HQ Lease. 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 is 188 months and began in November 2020. Upon certain conditions, the Company has two ten-year options to extend the lease, both of which are not reasonably assured of exercise. The Company has received $3.0 million of tenant improvement allowances for costs related to the design and construction of certain Company improvements.

The Company maintains letters of credit for the benefit of landlords which is disclosed as restricted cash in the condensed consolidated balance sheets. Restricted cash related to letters of credit due to landlords was $6.0 million as of September 30, 2023 and December 31, 2022.

The balance sheet classification of our lease liabilities were as follows (in thousands):


	September 30, 2023		December 31, 2022
Operating lease liabilities
Current portion included in accrued and other current liabilities	$	6,578	$	6,002
Long-term portion of lease liabilities	90,102		95,122
Total operating lease liabilities	$	96,680	$	101,124

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


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Operating lease cost	$	3,180	$	3,177	$	9,536	$	8,476
Variable lease cost	587		616		1,950		1,468
Total lease costs	$	3,767	$	3,793	$	11,486	$	9,944

Cash paid for amounts included in the measurement of lease liabilities for the nine months ended September 30, 2023 was $9.0 million and was included in net cash used in operating activities in the Company's condensed consolidated statements of cash flows.

The undiscounted future non-cancellable lease payments under the Company's operating leases as of September 30, 2023 were as follows:


Year ending December 31:	(In thousands)
2023 (remaining 3 months)	$	3,036
2024	12,447
2025	12,627
2026	12,819
2027	13,257
2028 and thereafter	77,235
Total undiscounted lease payments	131,421
Less: Present value adjustment	(34,741)
Total	$	96,680

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 6.89%. As of September 30, 2023, the weighted average remaining lease term for our operating leases is 9.27 years.

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 consolidated balance sheets as of September 30, 2023 and December 31, 2022.

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 September 30, 2023.

The Company enters into contracts in the normal course of business that includes arrangements with clinical research organizations, vendors for preclinical research and vendors for manufacturing. These agreements generally allow for cancellation with notice. As of September 30, 2023, the Company had non-cancellable purchase commitments of $4.0 million.

Commitments and Contingencies - Narrative (Details) $ in Millions	1 Months Ended	9 Months Ended
	Feb. 28, 2019 ft² renewal	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 ft²	Jul. 31, 2020 USD ($)	Oct. 31, 2018 USD ($) ft²	Aug. 31, 2018 ft²
Operating Leased Assets [Line Items]
Area of office and laboratory (in square feet) \| ft²						14,943	68,000
Operating lease term						124 months	127 months
Operating lease, option to extend term (in years)						7 years	7 years
Tenant improvements		$ 5.0
Additional area of office and laboratory (in square feet) \| ft²				47,566
Allowance for tenant improvements						$ 0.8
Letter of credit		6.0	$ 6.0
Cash paid for amounts included in measurement of lease liabilities		$ 9.0
Weighted average discount rate (as a percent)		6.89%
Weighted average remaining lease term (in years)		9 years 3 months 7 days
Agreement term					20 years
Termination payment					$ 4.3
Non-cancellable purchase commitments		$ 4.0
Lease One, Amended
Operating Leased Assets [Line Items]
Operating lease term				120 months
Operating lease, option to extend term (in years)				8 years
Lease Two
Operating Leased Assets [Line Items]
Operating lease, option to extend term (in years)				8 years
Letter of Credit
Operating Leased Assets [Line Items]
Letter of credit		4.3	$ 4.3
Newark
Operating Leased Assets [Line Items]
Operating lease term	188 months
Operating lease, option to extend term (in years)	10 years
Area of operating lease (in square feet) \| ft²	118,000
Number of options to extend lease \| renewal	2
Tenant improvement allowance utilized to date		$ 3.0