Adicet Bio (ACET) 10-Q 8 Nov 23 2023 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2023	Nov. 06, 2023
Cover [Abstract]
Entity Incorporation, State or Country Code	DE
Entity Common Stock, Shares Outstanding		43,164,522
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2023
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2023
Entity Registrant Name	Adicet Bio, Inc.
Entity Central Index Key	0001720580
Trading Symbol	ACET
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity File Number	001-38359
Entity Tax Identification Number	81-3305277
Entity Address, Address Line One	200 Berkeley Street
Entity Address, Address Line Two	19th Floor
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02116
City Area Code	650
Local Phone Number	503-9095
Security Exchange Name	NASDAQ
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Document Quarterly Report	true
Document Transition Report	false

Consolidated Balance Sheets (un

Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 183,257	$ 257,656
Prepaid expenses and other current assets	2,626	3,382
Total current assets	185,883	261,038
Property and equipment, net	28,273	28,710
Operating lease right-of-use asset	18,185	20,269
Goodwill	0	19,462
Other non-current assets	916	1,211
Total assets	233,257	330,690
Current liabilities:
Accounts payable	4,066	4,404
Accrued and other current liabilities	12,574	12,811
Operating lease liability	3,128	2,492
Total current liabilities	19,768	19,707
Operating lease liability, net of current portion	18,669	18,531
Other non-current liabilities	143	114
Total liabilities	38,580	38,352
Commitments and contingencies (Note 10)
Stockholders’ equity:
Preferred stock, $0.0001 par value, 10,000,000 shares authorized as of September 30, 2023 and December 31, 2022, respectively; none issued and outstanding as of September 30, 2023 and December 31, 2022, respectively	0	0
Common stock, $0.0001 par value, 150,000,000 shares authorized as of September 30, 2023 and December 31, 2022, respectively; 43,107,921 and 42,954,820 shares issued and outstanding as of September 30, 2023 and December 31, 2022, respectively	4	4
Additional paid-in capital	545,956	530,448
Accumulated deficit	(351,283)	(238,114)
Total stockholders’ equity	194,677	292,338
Total liabilities and stockholders’ equity	$ 233,257	$ 330,690

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) (unaudited) - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	43,107,921	42,954,820
Common stock, shares outstanding	43,107,921	42,954,820
Preferred Stock, par value	$ 0.0001	$ 0.0001
Preferred stock shares authorized	10,000,000	10,000,000
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Revenue related party	$ 0	$ 0	$ 0	$ 24,990
Operating expenses:
Research and development	26,167	16,570	81,284	46,231
General and administrative	6,633	6,415	19,726	19,745
Goodwill impairment	19,462	0	19,462	0
Total operating expenses	52,262	22,985	120,472	65,976
Loss from operations	(52,262)	(22,985)	(120,472)	(40,986)
Interest income	2,520	1,224	7,800	1,581
Interest expense	(1)	(18)	(25)	(54)
Other expense, net	(142)	(217)	(472)	(456)
Loss before income tax provision	(49,885)	(21,996)	(113,169)	(39,915)
Income tax provision	0	0	0	0
Net loss	$ (49,885)	$ (21,996)	$ (113,169)	$ (39,915)
Net loss per share attributable to common stockholders, basic	$ (1.16)	$ (0.53)	$ (2.63)	$ (0.98)
Net loss per share attributable to common stockholders, diluted	$ (1.16)	$ (0.53)	$ (2.63)	$ (0.98)
Weighted-average common shares used in computing net income (loss) per share attributable to common stockholders, basic	42,980,641	41,642,815	43,001,901	40,547,792
Weighted-average common shares used in computing net income (loss) per share attributable to common stockholders, diluted	42,980,641	41,642,815	43,001,901	40,547,792

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Additional Pain In Capital	Accumulated Deficit
Balance at Dec. 31, 2021	$ 303,129	$ 4	$ 471,449	$ (168,324)
Balance, shares at Dec. 31, 2021		39,736,914
Issuance of common stock upon exercise of stock options	93		93
Issuance of common stock upon exercise of stock options, shares		10,099
Issuance of common stock upon vesting of restricted stock, shares		224,000
Shares withheld for taxes	1,106		1,106
Shares withheld for taxes, shares		(85,197)
Stock-based compensation expense	4,350		4,350
Net income	4,618			4,618
Balance at Mar. 31, 2022	311,084	$ 4	474,786	(163,706)
Balance, shares at Mar. 31, 2022		39,885,816
Balance at Dec. 31, 2021	303,129	$ 4	471,449	(168,324)
Balance, shares at Dec. 31, 2021		39,736,914
Net income	(39,915)
Balance at Sep. 30, 2022	317,658	$ 4	525,894	(208,240)
Balance, shares at Sep. 30, 2022		42,787,657
Balance at Mar. 31, 2022	311,084	$ 4	474,786	(163,706)
Balance, shares at Mar. 31, 2022		39,885,816
Issuance of common stock upon exercise of stock options	183		183
Issuance of common stock upon exercise of stock options, shares		17,854
Issuance of common stock upon vesting of restricted stock, shares		100,731
Shares withheld for taxes	203		203
Shares withheld for taxes, shares		16,354
Stock-based compensation expense	4,335		4,335
Net income	(22,538)			(22,538)
Balance at Jun. 30, 2022	293,267	$ 4	479,507	(186,244)
Balance, shares at Jun. 30, 2022		40,020,755
Issuance of common stock upon exercise of stock options	191		191
Issuance of common stock upon exercise of stock options, shares		23,216
Issuance of common stock upon vesting of restricted stock, shares		209,375
Shares withheld for taxes	1,355		1,355
Shares withheld for taxes, shares		(77,412)
Stock-based compensation expense	4,191		4,191
Net income	(21,996)			(21,996)
Issuance of common stock from Atm offering net of sales agent commission and fees amount	43,360		43,360
Issuance of common stock from Atm offering net of sales agent commission and fees shares , shares		2,611,723
Balance at Sep. 30, 2022	317,658	$ 4	525,894	(208,240)
Balance, shares at Sep. 30, 2022		42,787,657
Balance at Dec. 31, 2022	292,338	$ 4	530,448	(238,114)
Balance, shares at Dec. 31, 2022		42,954,820
Issuance of common stock upon exercise of stock options	3		3
Issuance of common stock upon exercise of stock options, shares		713
Issuance of common stock upon vesting of restricted stock, shares		3,205
Shares withheld for taxes	10		10
Shares withheld for taxes, shares		(1,307)
Stock-based compensation expense	4,765		4,765
Net income	(30,881)			(30,881)
Balance at Mar. 31, 2023	266,215	$ 4	535,206	(268,995)
Balance, shares at Mar. 31, 2023		42,957,431
Balance at Dec. 31, 2022	$ 292,338	$ 4	530,448	(238,114)
Balance, shares at Dec. 31, 2022		42,954,820
Issuance of common stock upon exercise of stock options, shares	946
Net income	$ (113,169)
Balance at Sep. 30, 2023	194,677	$ 4	545,956	(351,283)
Balance, shares at Sep. 30, 2023		43,107,921
Balance at Mar. 31, 2023	266,215	$ 4	535,206	(268,995)
Balance, shares at Mar. 31, 2023		42,957,431
Issuance of common stock upon exercise of stock options	1		1
Issuance of common stock upon exercise of stock options, shares		233
Purchase of common stock under ESPP	225		225
Purchase of common stock under ESPP Shares		108,494
Stock-based compensation expense	5,023		5,023
Net income	(32,403)			(32,403)
Balance at Jun. 30, 2023	239,061	$ 4	540,455	(301,398)
Balance, shares at Jun. 30, 2023		43,066,158
Issuance of common stock upon vesting of restricted stock, shares		66,750
Shares withheld for taxes	59		59
Shares withheld for taxes, shares		(24,987)
Stock-based compensation expense	5,560		5,560
Net income	(49,885)			(49,885)
Balance at Sep. 30, 2023	$ 194,677	$ 4	$ 545,956	$ (351,283)
Balance, shares at Sep. 30, 2023		43,107,921

Consolidated Statements of St_2

Consolidated Statements of Stockholders Equity (Parenthetical) $ in Millions	3 Months Ended
	Sep. 30, 2022 USD ($)
Statement of Stockholders' Equity [Abstract]
Stock issuance cost	$ 1.6

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities
Net income (loss)	$ (113,169)	$ (39,915)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	4,409	1,516
Noncash lease expense	2,083	1,712
Stock-based compensation expense	15,348	12,876
Loss on disposal of property and equipment	0	55
Goodwill, Impairment Loss	19,462	0
Loss on disposal of lease assets	0	(1)
Amortization of deferred debt issuance costs	29	18
Changes in operating assets and liabilities:
Accounts receivable - related party	0	156
Prepaid expenses and other current assets	756	1,696
Other non-current assets	265	933
Accounts payable	(223)	556
Contract liabilities — related party	0	(4,805)
Operating lease liabilities	773	(1,571)
Accrued and other current and non-current liabilities	36	846
Net cash used in operating activities	(70,231)	(25,928)
Cash flows from investing activities
Purchases of property and equipment	(4,328)	(10,292)
Net cash provided by (used in) investing activities	(4,328)	(10,292)
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	0	43,360
Proceeds from exercise of stock options	4	468
Proceeds from Employee Stock Purchase Plan	225	203
Taxes withheld and paid related to net share settlement of equity awards	(69)	(2,461)
Deferred issuance costs	0	(365)
Net cash provided by (used in) financing activities	160	41,205
Net change in cash, cash equivalents and restricted cash	(74,399)	4,985
Cash, cash equivalents and restricted cash, at the beginning of period	257,656	277,694
Cash, cash equivalents and restricted cash, at the end of period	183,257	282,679
Supplemental disclosures of noncash investing and financing activities
Purchases of property and equipment included in accounts payable and accrued expenses	105	7,111
Operating right-of-use assets obtained in exchange for operating lease liabilities	$ 0	$ 2,343

Organization and Nature of Busi

Organization and Nature of Business	9 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Nature of Business	1. Organization and Nature of the Business Adicet Bio, Inc. (formerly resTORbio, Inc. (resTORbio), together with its subsidiaries, the Company) is a clinical stage biotechnology company discovering and developing allogeneic gamma delta T cell therapies for cancer. The Company is advancing a pipeline of “off-the-shelf” gamma delta T cells, engineered with chimeric antigen receptors (CARs) to enhance selective tumor targeting and facilitate innate and adaptive anti-tumor immune response for durable activity in patients. The Company's approach to activate, engineer, and manufacture allogeneic gamma delta T cell product candidates derived from the peripheral blood cells of unrelated donors allows it to generate new product candidates in a rapid and cost-efficient manner. Adicet Bio, Inc. (when referred to prior to the merger, Former Adicet) was incorporated in November 2014 in Delaware. On September 15, 2020, Former Adicet completed a merger (Merger) with resTORbio, pursuant to which Former Adicet merged with a wholly owned subsidiary of resTORbio in an all-stock transaction with Former Adicet surviving as a wholly owned subsidiary of resTORbio and changing its name to “Adicet Therapeutics, Inc.” (Adicet Therapeutics). In connection with the Merger, the Company changed its name from “resTORbio, Inc.” to “Adicet Bio, Inc.” The Company’s principal executive offices are located in Boston, Massachusetts. The Company also has offices in Redwood City, California. Adicet Bio Israel Ltd. (formerly Applied Immune Technologies Ltd.) (Adicet Israel) is a wholly owned subsidiary of the Company and is located in Haifa, Israel. Adicet Israel was founded in 2006. During 2019, the Company consolidated its operations, including research and development activities, in the United States and as a result, substantially reduced its operations in Israel. Liquidity The Company has incurred significant net operating losses and negative cash flows from operations and has an accumulated deficit of $ 351.3 million as of September 30, 2023. The Company has historically financed its operations primarily through a collaboration and licensing arrangement, public and private placements of equity securities and debt, and cash received in the Merger with resTORbio. To date, none of the Company’s product candidates have been approved for sale and therefore the Company has not generated any revenue from product sales. Management expects operating losses and negative cash flows to continue for the foreseeable future, until such time, if ever, that it can generate significant sales of its product candidates currently in development. On March 12, 2021, the Company entered into a Capital On Demand™ Sales Agreement (the Sales Agreement) with JonesTrading Institutional Services LLC, as sales agent, to provide for the offering, issuance and sale of up to an aggregate amount of $ 75.0 million of shares of common stock from time to time in “at-the-market” (ATM) offerings under a registration statement on Form S-3 (File No. 333-254193) (2021 Shelf Registration Statement) filed with the U.S. Securities and Exchange Commission (the SEC), which was declared effective on March 30, 2021. In August 2022, pursuant to the Sales Agreement and subject to the limitations thereof, the Company sold an aggregate of 2,611,723 shares of common stock at $ 17.23 per share resulting in net proceeds to the Company of $ 43.4 million after deducting sales agent commissions and expenses. In November 2022, the Company filed a new prospectus supplement to the 2021 Shelf Registration Statement for the offer and sale of up to $ 100.0 million of shares of common stock from time to time through the sales agent, which includes the $ 30.0 million of shares of common stock not sold under the original prospectus and up to an additional $ 70.0 million of shares of common stock (the ATM Program). No shares of common stock have been sold to date under the ATM Program. The Company expects that its cash and cash equivalents, including the net proceeds it received from its ATM offering, will be sufficient to fund its forecasted operating expenses, capital expenditure requirements and debt service payments for at least the next twelve months from the issuance of these interim consolidated financial statements. All of the Company’s revenue to date has been generated from a collaboration and license agreement with Regeneron Pharmaceuticals Inc, (Regeneron). The Company does not expect to generate any significant product revenue until it obtains regulatory approval of and commercializes any of the Company’s product candidates or enters into additional collaborative agreements with third parties, and it does not know when, or if, either will occur. The Company expects to continue to incur significant losses for the foreseeable future, and it expects the losses to increase as the Company continues the development of, and seeks regulatory approvals for, its product candidates and begins to commercialize any approved products. The Company is subject to all of the risks typically related to the development of new product candidates, including, but not limited to, raising additional capital, development by its competitors of new technological innovations, risk of failure in preclinical and clinical studies, safety and efficacy of its product candidates in clinical trials, the risk of relying on external parties such as contract research organizations (CROs) and contract development and manufacturing organizations (CDMOs), the regulatory approval process, market acceptance of the Company’s products once approved, lack of marketing and sales history, dependence on key personnel and protection of proprietary technology and it may encounter unforeseen expenses, difficulties, complications, delays, and other unknown factors that may adversely affect its business. Until such time as the Company can generate significant revenue from product sales, if ever, the Company expects to finance its operations through the sale of equity, debt financings, collaborative or other arrangements with corporate or other sources of financing. Adequate funding may not be available to the Company on acceptable terms or at all. The Company’s failure to raise capital as and when needed could have a negative impact on its financial condition and the Company’s ability to pursue its business strategies. Although the Company continues to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The unaudited interim consolidated financial statements and related disclosures have been prepared in conformity with accounting principles generally accepted in the United States of America (United States GAAP or GAAP). Significant Accounting Policies The Company’s significant accounting policies are described in Note 2, "Summary of Significant Accounting Policies," to the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022 (the Annual Report). There have been no material changes to the significant accounting policies during the nine months ended September 30, 2023 . Unaudited Interim Financial Information The accompanying unaudited consolidated financial statements as of September 30, 2023, and for the three and nine months ended September 30, 2023, have been prepared by the Company, pursuant to the rules and regulations of the SEC, for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. However, the Company believes that the disclosures are adequate to make the information presented not misleading. These unaudited consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2022. In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s consolidated financial position as of September 30, 2023 and consolidated results of operations for the three and nine months ended September 30, 2023 and 2022 and consolidated cash flows for the nine months ended September 30, 2023 and 2022 have been made. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2023. Concentration of Credit Risk Financial instruments, which potentially subject the Company to concentrations of credit risk, consist principally of cash and cash equivalents. The Company’s cash and cash equivalents are held at two financial institutions in the U.S. and one financial institution in Israel and such amounts may, at times, exceed insured limits. The Company invests its cash equivalents in treasury securities. The Company limits its credit risk associated with cash equivalents by placing them with banks and institutions it believes are highly creditworthy and in highly rated investments. The Company has not experienced any losses on its deposits of cash and cash equivalents to date. Risks and Uncertainties The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical studies, clinical trials, and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance and reporting. The Company’s product candidates are still in development and, to date, none of the Company’s product candidates have been approved for sale and, therefore, the Company has not generated any revenue from product sales. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained or maintained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from other pharmaceutical and biotechnology companies. Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) or other standard setting bodies and adopted by the Company as of the specified effective date, unless otherwise discussed below. Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13), which requires the measurement and recognition of expected credit losses for financial assets held at amortized cost. This ASU replaces the existing incurred loss impairment model with an expected loss model. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. These changes will result in earlier recognition of credit losses. For SEC filers that are eligible to be smaller reporting companies, this ASU is effective for fiscal years beginning after December 15, 2022, and interim periods within those fiscal years. Early adoption is permitted. The Company adopted the provisions of ASU 2016-13 in the first quarter of 2023. There was no impact to the consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU No. 2017-04, Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment (ASU 2017-04). The new guidance simplifies the subsequent measurement of goodwill by removing the second step of the two-step impairment test. The amendment requires an entity to perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. SEC filers that are eligible to be smaller reporting companies should adopt the amendments in this update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2022. The amendment should be applied on a prospective basis. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company adopted the provisions of ASU 2017-04 in the first quarter of 2023.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements The Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy which establishes three level of inputs that may be used to measure fair value, as follows: Level 1 — Observable inputs, such as quoted prices in active markets for identical assets or liabilities. Level 2 — Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 — Unobservable inputs which reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model. In determining fair value, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as considers counterparty credit risk in its assessment of fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): September 30, 2023 Level 1 Level 2 Level 3 Total Assets: Treasury securities (1) (2) $ 134,349 $ — $ — $ 134,349 Total fair value of assets $ 134,349 $ — $ — $ 134,349 December 31, 2022 Level 1 Level 2 Level 3 Total Assets: Money market funds (1) (3) $ 75,701 $ — $ — $ 75,701 Total fair value of assets $ 75,701 $ — $ — $ 75,701 (1) Included in cash and cash equivalents in the consolidated balance sheets. (2) Treasury securities are included within Level 1 of the fair value hierarchy because they are actively traded and valued using quoted market prices. (3) Money market funds are included within Level 1 of the fair value hierarchy because they are valued using quoted market prices.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	6 Months Ended
	Jun. 30, 2023
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid Expenses and Other Current Assets	4. Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following (in thousands): September 30, December 31, Prepaid software subscription and licensing fees $ 618 $ 529 Prepaid maintenance 555 295 Prepaid insurance 463 1,251 Prepayments to CROs and CDMOs 295 492 Prepaid lab supplies 221 — Prepaid property taxes 76 61 Interest receivable 20 435 Other prepaid expenses and current assets 378 319 Total prepaid expenses and other current assets $ 2,626 $ 3,382

Property and Equipment, Net

Property and Equipment, Net	9 Months Ended
	Sep. 30, 2023
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	5. Property and Equipment, net Property and equipment, net consisted of the following (in thousands): Useful life September 30, December 31, Laboratory equipment 3 $ 12,863 $ 7,503 Leasehold improvements Lesser of useful life or lease term 26,617 19,959 Furniture and fixtures 3 951 184 Construction in progress — 473 9,292 Computer equipment 3 178 172 Software 3 353 353 41,435 37,463 Less: Accumulated depreciation and amortization ( 13,162 ) ( 8,753 ) Property and equipment, net $ 28,273 $ 28,710 Depreciation and amortization expense was $ 1.6 million and $ 0.8 million for the three months ended September 30, 2023 and 2022, respectively. Depreciation and amortization expense was $ 4.4 million and $ 1.5 million for the nine months ended September 30, 2023 and 2022, respectively. The increase in expense is primarily due to the completion and subsequent depreciation of the Company's good manufacturing practice (GMP) cell processing and vector manufacturing suite at the Company's office in Redwood City, California (1000 Bridge Parkway) which was completed in February 2023. Construction in progress has decreased by $ 8.8 million during the nine months ended September 30, 2023 , compared to the balance at December 31, 2022, due to the Company's completion of the Company's GMP cell processing and vector manufacturing suite in February 2023. The remaining $0 .5 million in construction in progress as of September 30, 2023 is primarily related to lab and computer equipment not yet placed into service.

Accrued and Other Current Liabi

Accrued and Other Current Liabilities	9 Months Ended
	Sep. 30, 2023
Payables and Accruals [Abstract]
Accrued and Other Current Liabilities	6. Accrued and Other Current Liabilities Accrued and other current liabilities consisted of the following (in thousands): September 30, December 31, Accrued compensation $ 5,713 $ 5,703 Accrued CDMO costs 5,471 4,390 Accrued CRO costs 134 657 Accrued professional services 626 1,356 Accrued other research and development expenses 599 674 Accrued other liabilities 31 31 Total accrued and other liabilities $ 12,574 $ 12,811

Term Loan

Term Loan	9 Months Ended
	Sep. 30, 2023
Term Loan [Abstract]
Term Loan	7. Term Loan On April 28, 2020, the Company entered into a Loan and Security Agreement (the Loan Agreement) as amended on July 8, 2020, September 14, 2020, September 15, 2020, October 21, 2022, December 2, 2022 (the 2022 Loan Amendment) and May 30, 2023 with Pacific Western Bank (PacWest). On March 13, 2023, the Company and PacWest executed a letter agreeing that, notwithstanding the covenants included in the 2022 Loan Amendment, until June 30, 2023 (i) the Company and its subsidiaries will not be required to maintain the lesser of $ 200 million or seventy percent (70%) of its combined balances in demand deposit accounts, money market funds and/or insured cash sweep (ICS) accounts with PacWest and (ii) the Company must maintain its combined balances at PacWest or its affiliates, including Pacific Western Asset Management (the Letter). On May 30, 2023, the Company further amended its Loan Agreement with PacWest (the 2023 Loan Amendment). Pursuant to the 2023 Loan Amendment, the Company must maintain the lesser of (i) $ 35.0 million or (ii) all of the Company’s combined balances in demand deposit accounts, money market accounts, and/or insured cash sweep accounts with PacWest. If the Company’s total cash and investments drop to less than $ 35.0 million, the 2023 Loan Amendment permits the Company to maintain cash and/or investments in one or more accounts outside of PacWest up to a total of $ 2.5 million. As of September 30, 2023 , the Company has $ 12.7 million available under the Loan Agreement. Additionally, as of the date of this Quarterly Report on Form 10-Q, the Company is in compliance with such covenants as stated in the 2023 Loan Amendment and had no indebtedness outstanding under the Loan Agreement.

Third Party Agreements

Third Party Agreements	9 Months Ended
	Sep. 30, 2023
Revenue Recognition and Deferred Revenue [Abstract]
Third Party Agreements	8. Third Party Agreements Regeneron On July 29, 2016, the Company entered into a license and collaboration agreement with Regeneron, which was amended in April 2019, with such amendment becoming effective in connection with Regeneron’s investment in the Company’s Series B redeemable convertible preferred stock private placement transaction in July 2019 (as amended, the Regeneron Agreement). Financial Terms. The Company received a non-refundable upfront payment of $ 25.0 million from Regeneron upon execution of the Regeneron Agreement and an aggregate of $ 20.0 million of additional payments for research funding from Regeneron as of September 30, 2023 . In addition, Regeneron may have to pay the Company additional amounts in the future consisting of up to an aggregate of $ 80.0 million of option exercise fees, as specified in the Regeneron Agreement. Per the terms of the agreement, Regeneron must pay the Company high single digit royalties as a percentage of net sales for immune cell products (ICPs) to targets for which it has exclusive rights, and low single digit royalties as a percentage of net sales on any non-ICP product comprising a targeting moiety generated by the Company through the use of Regeneron’s proprietary mice. The Company must pay Regeneron mid-single to low double digit, but less than teens, of royalties as a percentage of net sales of ICPs to targets for which the Company has exercised exclusive rights, and low to mid-single digit of royalties as a percentage of net sales of targeting moieties generated from the Company’s license to use Regeneron’s proprietary mice. Royalties are payable until the longer of the expiration or invalidity of the licensed patent rights or twelve (12) years from first commercial sale. No royalties have been earned or paid under the Regeneron Agreement through September 30, 2023. On January 28, 2022, Regeneron exercised its option to license the exclusive, worldwide rights to ADI-002, an allogeneic gamma delta CAR T cell therapy directed against Glypican-3, pursuant to the Regeneron Agreement. In conjunction with the exercise of the option, Regeneron paid an exercise fee of $ 20.0 million to the Company on January 28, 2022, and the Company completed the transfer of the associated license rights to Regeneron during the first quarter of 2022. The $ 20.0 million option exercise fee, plus $ 5.0 million of revenue recognized relating to the combined performance obligation, resulted in an aggregate of $ 25.0 million recorded as revenue for the nine months ended September 30, 2022. The Company's obligations under the combined performance obligation were completed during the year ended December 31, 2022. Regeneron is responsible, at its sole cost, for all development, manufacturing and commercialization of ADI-002 and must pay the Company high single digit royalties as a percentage of any net sales of ADI-002 for a period commencing on the first commercial sale until the longer of (i) the expiration or invalidity of the licensed patent rights or (ii) a low double digit amount of years from first commercial sale. As of September 30, 2023 and 2022, there were no contract assets related to the Regeneron Agreement. The following tables present changes in the Company’s contract liabilities for the nine months ended September 30, 2023 and 2022 (in thousands): Nine Months Ended September 30, 2023 Balance at Deductions Balance at Contract liability $ — $ — $ — Nine Months Ended September 30, 2022 Balance at Deductions Balance at Contract liability $ 4,805 $ ( 4,805 ) $ — (1) Deductions to contract liabilities relate to deferred revenue recognized as revenue during the reporting period. Twist Bioscience In March 2021, the Company entered into an Antibody Discovery Agreement (the Twist Agreement) with Twist Bioscience Corporation (Twist). Under the terms of the Twist Agreement, Twist will utilize its proprietary platform technology to assist the Company with the discovery of novel antibodies related to target antigens selected by the Company. The Company maintains the sole and exclusive rights to any program antibodies discovered under the Twist Agreement and has the right to patent, assign, license or transfer any work product under the agreement. Furthermore, the Company has the right to sublicense its rights to program antibodies to third parties. The Company may terminate the Twist Agreement at any time, with or without cause, upon a specified period advance written notice. Per the terms of the agreement, the Company will pay Twist an upfront, non-refundable project initiation fee, a technology access fee, as well as a project fee for each project entered into under the agreement. Additionally, the Company will pay fees for development and regulatory milestones in the tens of millions of dollars and low single digit royalties on net sales to Twist for programs initiated under the agreement. In November 2022, the Company entered into an amendment to the Twist Agreement (the Twist Amendment). The Twist Amendment updates the language associated with Twist's audit rights as well as the amounts associated with technology access fees. On a cumulative basis as of September 30, 2023 , the Company has incurred and expensed $ 1.0 million related to project initiation fees, technology access fees and projects fees as research and development expense related to this agreement.

Commitments and Contingences

Commitments and Contingences	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingences	9. Commitments and Contingencies Operating Leases The Company leases office and laboratory space in Redwood City, California, and Boston, Massachusetts. Redwood City In 2018, Adicet Therapeutics executed a non-cancelable lease agreement, as amended in 2022, pursuant to which the Company leases office and laboratory facility at 1000 Bridge Parkway and a portion of 1200 Bridge Parkway in Redwood City, California (the Redwood City Lease). On January 9, 2023, Adicet Therapeutics entered into a third lease amendment with Westport Office Park, LLC (the Third Amendment). The Third Amendment further amends the Redwood City Lease and increases the tenant improvement allowance as of January 1, 2023 by an additional $ 3.0 million. The Company expects to utilize the full allowance for the continued buildout of office and laboratory space at 1000 Bridge Parkway. Per the terms of this amendment, this additional allowance will be repaid through equal monthly payments of principal amortization and interest on a monthly basis over the term of the lease at an interest rate of eight percent ( 8 %) per annum. The Company received the allowance on February 21, 2023. On August 7, 2023, Adicet Therapeutics entered into a fourth lease amendment with Westport Office Park, LLC (the Fourth Amendment). The Fourth Amendment amends the period over which the tenant improvement allowance received in the Third Amendment will be amortized and identifies the monthly amortization payable by the Company. On September 1, 2023, Adicet Therapeutics amended its letter of credit with Westport Office Park, LLC. The amendment reduced the amount of the letter of credit associated with 1000 Bridge Parkway by $ 2.1 million resulting in an updated letter of credit amount of $2.1 million. Boston In 2018, the Company entered into a lease agreement, as amended in 2019, for office space at 500 Boylston St, Boston, Massachusetts (500 Boylston Lease). Under the terms of the 500 Boylston Lease, the Company was permitted to assign, sublease or transfer this lease, with the consent of the landlord. On July 19, 2021, the Company entered into a sublease agreement with RFS OPCO LLC (Sublessee), whereby the Company agreed to sublease to Sublessee all of the 9,501 rentable square feet of 500 Boylston St. The expected undiscounted cash flows to be received from the sublease as of September 30, 2023 is as follows (in thousands): September 30, 2023 $ 177 2024 722 2025 736 2026 438 2027 and thereafter — Total $ 2,073 Further, the Company remains liable for the remaining lease payments under the Master Lease, totaling $ 1.8 million, which is included in the future minimum lease payments table below. The future minimum lease payments under all non-cancelable operating lease obligations as of September 30, 2023 were as follows (in thousands): September 30, 2023 $ 1,241 2024 5,015 2025 4,662 2026 4,009 2027 and thereafter 12,090 Total undiscounted lease payments 27,017 Less: imputed interest 5,220 Total operating lease liability 21,797 Less: current portion ( 3,128 ) Operating lease liability, net of current maturities $ 18,669 The following table presents the operating lease cost and information related to the operating lease right-of-use assets, net and operating lease liabilities for the quarter ended September 30, 2023 (in thousands): Three Months Ended September 30, 2023 Lease Cost Operating lease cost $ 1,139 Short-term lease cost 49 Sublease income ( 179 ) Total lease cost $ 1,010 Other Information Operating cash flows used for lease liabilities $ 773 Weighted-average remaining lease term - operating leases 5.9 Weighted-average discount rate - operating leases 7 % For the nine months ended September 30, 2023 , the Company recognized $ 3.3 million and $ 0.1 million in operating lease and short-term lease costs, respectively. Additionally, for the nine months ended September 30, 2023 , the Company recognized $ 0.5 million in sublease income.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2023
Stockholders' Equity Note [Abstract]
Stockholders' Equity	10. Stockholders' Equity Common Stock The Company’s Certificate of Incorporation, as amended, authorized the Company to issue 150,000,000 shares of common stock, par value $ 0.0001 per share, as of September 30, 2023. Common stockholders are entitled to dividends if and when declared by the board of directors of the Company subject to the prior rights of the preferred stockholders. As of September 30, 2023 , no dividends on common stock had been declared by the board of directors. The Company has the following shares of common stock reserved for future issuance: September 30, December 31, Stock options and restricted stock units available for future grant 2,039,141 2,871,705 Stock options issued and outstanding 9,749,498 6,203,020 Unvested restricted stock units 586,800 197,580 Total common stock reserved 12,375,439 9,272,305

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	11. Stock-based Compensation Stock-based Compensation Expense Total stock-based compensation expense recognized was as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Research and development $ 2,545 $ 1,745 $ 7,132 $ 5,319 General and administrative 3,015 2,446 8,216 7,557 Total stock-based compensation $ 5,560 $ 4,191 $ 15,348 $ 12,876 Stock Options A summary of stock option activity for the nine months ended September 30, 2023 is set forth below: Number of Weighted Weighted- Aggregate Outstanding, December 31, 2022 6,203,020 $ 14.44 8.4 $ 780 Options granted 4,167,242 $ 5.48 Options exercised ( 946 ) $ 4.76 Options forfeited or cancelled ( 619,818 ) $ 12.35 Outstanding, September 30, 2023 9,749,498 $ 10.74 8.4 $ — Options exercisable, September 30, 2023 3,602,027 $ 13.87 7.6 $ — Vested and expected to vest, September 30, 2023 9,749,498 $ 10.74 8.4 $ — The assumptions used in the Black Scholes Model to calculate stock-based compensation are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Fair value of common stock $ 1.37 - $ 3.38 $ 14.16 - $ 16.89 $ 1.37 - $ 9.15 $ 11.49 - $ 19.97 Expected term (years) 5.5 - 6.1 6.0 - 6.1 5.5 - 6.1 5.5 - 6.1 Volatility 84.7 % - 87.3 % 79.5 % - 80.7 % 83.3 % - 87.3 % 77.4 % - 80.7 % Risk free rates 4.1 % - 4.6 % 2.7 % - 4.0 % 3.5 % - 4.6 % 1.6 % - 4.0 % Dividend rate 0.0 % 0.0 % 0.0 % 0.0 % Restricted Stock Units The summary of RSU activity and related information for the nine months ended September 30, 2023 is set forth below: Number of Units Outstanding Weighted Average Outstanding, December 31, 2022 197,580 $ 7.8 RSUs granted 513,700 $ 7.6 RSUs vested ( 69,955 ) $ 7.6 RSUs forfeited ( 54,525 ) $ 7.2 Outstanding, September 30, 2023 586,800 $ 7.8 Option repricing On August 8, 2023, the board of directors approved a stock option repricing (the Option Repricing) to be effective on August 14, 2023 (the Effective Date) in accordance with the terms of the Company’s 2015 Stock Incentive Plan and 2018 Plan (together, the Plans). Pursuant to the Option Repricing, the exercise price of each stock option previously granted under the Plans, totaling 6,431,077 options, was amended to reduce the exercise price of such options to $ 2.14 per share, the closing price of the Company’s common stock on the Nasdaq Global Market on the Effective Date. Under the terms of the Option Repricing, a repriced option will revert to its original exercise price if, prior to the one year anniversary of the Effective Date, (a) the option holder’s employment is terminated by the Company with cause or by the option holder or (b) the option is exercised. The repriced options otherwise retained their existing terms and conditions as set forth in the Plans and applicable award agreements. The stock option modification resulted in $ 4.6 million of incremental compensation cost, which was calculated using the Black-Scholes option-pricing model. Of the incremental compensation cost, $ 0.4 million was recognized in the three months ended September 30, 2023 , and $ 4.2 million will be recognized on the straight-line basis over the remaining vesting period of the repriced options. The incremental cost is included in general and administrative expense and research and development expense on the condensed consolidated statements of operations and comprehensive loss. In addition, as of the Effective Date, the Company issued 1,418,042 options to purchase shares of common stock under the 2018 Plan to eligible employees who held inducement awards as of August 8, 2023. These new options were issued to eligible employees because their inducement awards granted under Nasdaq Listing Rule 5635(c)(4) are not eligible for repricing. The prior inducement awards remain outstanding under their original terms.

Net Loss per Share

Net Loss per Share	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Net Loss per Share	12. Net Loss per Share The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share data): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Net loss - basic and diluted $ ( 49,885 ) $ ( 21,996 ) $ ( 113,169 ) $ ( 39,915 ) Weighted-average shares used in computing net loss per share, basic and diluted 42,980,641 41,642,815 43,001,901 40,547,792 Net loss per share, basic and diluted ( 1.16 ) ( 0.53 ) ( 2.63 ) ( 0.98 ) The following outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share for the period presented because including them would have been antidilutive: As of September 30, 2023 2022 Options to purchase common stock 9,749,498 5,862,935 Unvested restricted stock units 586,800 318,160 Total 10,336,298 6,181,095

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	13. Income Taxes The Company recognized no income tax expense during the three and nine months ended September 30, 2023 and 2022. The Company maintains a full valuation allowance against its deferred tax assets due to the Company’s history of losses as of September 30, 2023 .

Related Party

Related Party	9 Months Ended
	Sep. 30, 2023
Related Party Transactions [Abstract]
Related Party	14. Related Party As of September 30, 2023 , Regeneron owned 883,568 shares of the Company’s common stock. Regeneron became a related party in July 2019 as a result of Series B redeemable convertible preferred stock financing which was subsequently converted into common stock. For the three and nine months ended September 30, 2023 , the Company recorded no revenue from the Regeneron Agreement. See Note 8 for a discussion of the Regeneron Agreement.

Goodwill Impairment

Goodwill Impairment	9 Months Ended
	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill Impairment	15. Goodwill Impairment As discussed in Note 2 of the Company’s audited consolidated financial statements included in the Annual Report, goodwill is tested annually for impairment during the fourth quarter or earlier upon the occurrence of certain events or substantive changes in circumstances that indicate goodwill is more likely than not impaired. In connection with the annual goodwill impairment analysis performed during the fourth quarter of 2022, the Company determined that the fair value of its sole reporting unit exceeded its book value, and therefore no goodwill impairment charge was recorded in 2022. During the first and second quarters of 2023, the Company concluded that no events or changes in circumstances had occurred that indicated goodwill was more likely than not impaired. During the third quarter of 2023, the Company experienced a significant decline in its stock price. As of September 30, 2023, the Company’s stock price has declined 44 % from its closing stock price on June 30, 2023, and the decline in stock price has been sustained since that date. The Company determined that this decline in stock price and market capitalization of the Company constituted a substantive change in circumstances that would more likely than not reduce the fair value of the Company’s single reporting unit below its carrying amount. Accordingly, the Company tested its goodwill for impairment as of September 30, 2023 (the Interim Testing Date). In determining the fair value of the Company’s sole reporting unit for the interim impairment analysis, the Company used a market-based approach, and the primary input in this approach was a quoted market price in an active market. To determine the estimated fair value of the Company’s single reporting unit, the Company calculated its market capitalization based on its stock price. Based on the Company’s interim impairment analysis as of the Interim Testing Date, the carrying value of the Company’s single reporting unit exceeded its fair value. Accordingly, step two of the goodwill impairment test was performed. In performing step two of the goodwill impairment test, the Company utilized observable inputs and concluded that an impairment charge was necessary for the full amount of goodwill. As a result of the step two evaluation, the Company recorded a goodwill impairment charge of $ 19.5 million during the three months ended September 30, 2023 .

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The unaudited interim consolidated financial statements and related disclosures have been prepared in conformity with accounting principles generally accepted in the United States of America (United States GAAP or GAAP).
Significant Accounting Policies	Significant Accounting Policies The Company’s significant accounting policies are described in Note 2, "Summary of Significant Accounting Policies," to the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022 (the Annual Report). There have been no material changes to the significant accounting policies during the nine months ended September 30, 2023 .
Unaudited Interim Financial Information	Unaudited Interim Financial Information The accompanying unaudited consolidated financial statements as of September 30, 2023, and for the three and nine months ended September 30, 2023, have been prepared by the Company, pursuant to the rules and regulations of the SEC, for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. However, the Company believes that the disclosures are adequate to make the information presented not misleading. These unaudited consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2022. In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s consolidated financial position as of September 30, 2023 and consolidated results of operations for the three and nine months ended September 30, 2023 and 2022 and consolidated cash flows for the nine months ended September 30, 2023 and 2022 have been made. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2023.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments, which potentially subject the Company to concentrations of credit risk, consist principally of cash and cash equivalents. The Company’s cash and cash equivalents are held at two financial institutions in the U.S. and one financial institution in Israel and such amounts may, at times, exceed insured limits. The Company invests its cash equivalents in treasury securities. The Company limits its credit risk associated with cash equivalents by placing them with banks and institutions it believes are highly creditworthy and in highly rated investments. The Company has not experienced any losses on its deposits of cash and cash equivalents to date.
Risks and Uncertainties	Risks and Uncertainties The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical studies, clinical trials, and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance and reporting. The Company’s product candidates are still in development and, to date, none of the Company’s product candidates have been approved for sale and, therefore, the Company has not generated any revenue from product sales. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained or maintained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from other pharmaceutical and biotechnology companies.
Recent Accounting Pronouncements	Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) or other standard setting bodies and adopted by the Company as of the specified effective date, unless otherwise discussed below. Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13), which requires the measurement and recognition of expected credit losses for financial assets held at amortized cost. This ASU replaces the existing incurred loss impairment model with an expected loss model. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. These changes will result in earlier recognition of credit losses. For SEC filers that are eligible to be smaller reporting companies, this ASU is effective for fiscal years beginning after December 15, 2022, and interim periods within those fiscal years. Early adoption is permitted. The Company adopted the provisions of ASU 2016-13 in the first quarter of 2023. There was no impact to the consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU No. 2017-04, Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment (ASU 2017-04). The new guidance simplifies the subsequent measurement of goodwill by removing the second step of the two-step impairment test. The amendment requires an entity to perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. SEC filers that are eligible to be smaller reporting companies should adopt the amendments in this update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2022. The amendment should be applied on a prospective basis. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company adopted the provisions of ASU 2017-04 in the first quarter of 2023.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Schedule of Financial Assets and Liabilities Measured on Recurring Basis	The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): September 30, 2023 Level 1 Level 2 Level 3 Total Assets: Treasury securities (1) (2) $ 134,349 $ — $ — $ 134,349 Total fair value of assets $ 134,349 $ — $ — $ 134,349 December 31, 2022 Level 1 Level 2 Level 3 Total Assets: Money market funds (1) (3) $ 75,701 $ — $ — $ 75,701 Total fair value of assets $ 75,701 $ — $ — $ 75,701 (1) Included in cash and cash equivalents in the consolidated balance sheets. (2) Treasury securities are included within Level 1 of the fair value hierarchy because they are actively traded and valued using quoted market prices. (3) Money market funds are included within Level 1 of the fair value hierarchy because they are valued using quoted market prices.

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	6 Months Ended
	Jun. 30, 2023
Prepaid Expense and Other Assets, Current [Abstract]
Summary of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following (in thousands): September 30, December 31, Prepaid software subscription and licensing fees $ 618 $ 529 Prepaid maintenance 555 295 Prepaid insurance 463 1,251 Prepayments to CROs and CDMOs 295 492 Prepaid lab supplies 221 — Prepaid property taxes 76 61 Interest receivable 20 435 Other prepaid expenses and current assets 378 319 Total prepaid expenses and other current assets $ 2,626 $ 3,382

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	9 Months Ended
	Sep. 30, 2023
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): Useful life September 30, December 31, Laboratory equipment 3 $ 12,863 $ 7,503 Leasehold improvements Lesser of useful life or lease term 26,617 19,959 Furniture and fixtures 3 951 184 Construction in progress — 473 9,292 Computer equipment 3 178 172 Software 3 353 353 41,435 37,463 Less: Accumulated depreciation and amortization ( 13,162 ) ( 8,753 ) Property and equipment, net $ 28,273 $ 28,710

Accrued and Other Current Lia_2

Accrued and Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2023
Payables and Accruals [Abstract]
Summary of Accrued and Other Current Liabilities	Accrued and other current liabilities consisted of the following (in thousands): September 30, December 31, Accrued compensation $ 5,713 $ 5,703 Accrued CDMO costs 5,471 4,390 Accrued CRO costs 134 657 Accrued professional services 626 1,356 Accrued other research and development expenses 599 674 Accrued other liabilities 31 31 Total accrued and other liabilities $ 12,574 $ 12,811

Third Party Agreements (Tables)

Third Party Agreements (Tables)	9 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Change in Company's Contract Liabilities	The following tables present changes in the Company’s contract liabilities for the nine months ended September 30, 2023 and 2022 (in thousands): Nine Months Ended September 30, 2023 Balance at Deductions Balance at Contract liability $ — $ — $ — Nine Months Ended September 30, 2022 Balance at Deductions Balance at Contract liability $ 4,805 $ ( 4,805 ) $ — (1) Deductions to contract liabilities relate to deferred revenue recognized as revenue during the reporting period.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of Sublease Income	The expected undiscounted cash flows to be received from the sublease as of September 30, 2023 is as follows (in thousands): September 30, 2023 $ 177 2024 722 2025 736 2026 438 2027 and thereafter — Total $ 2,073
Summary of Lease Costs and Other Information	The following table presents the operating lease cost and information related to the operating lease right-of-use assets, net and operating lease liabilities for the quarter ended September 30, 2023 (in thousands): Three Months Ended September 30, 2023 Lease Cost Operating lease cost $ 1,139 Short-term lease cost 49 Sublease income ( 179 ) Total lease cost $ 1,010 Other Information Operating cash flows used for lease liabilities $ 773 Weighted-average remaining lease term - operating leases 5.9 Weighted-average discount rate - operating leases 7 %
Schedule of Future Minimum Lease Payments	The future minimum lease payments under all non-cancelable operating lease obligations as of September 30, 2023 were as follows (in thousands): September 30, 2023 $ 1,241 2024 5,015 2025 4,662 2026 4,009 2027 and thereafter 12,090 Total undiscounted lease payments 27,017 Less: imputed interest 5,220 Total operating lease liability 21,797 Less: current portion ( 3,128 ) Operating lease liability, net of current maturities $ 18,669

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2023
Stockholders' Equity Note [Abstract]
Schedule of Number of Shares of Common Stock Reserved for Future Issuance	The Company has the following shares of common stock reserved for future issuance: September 30, December 31, Stock options and restricted stock units available for future grant 2,039,141 2,871,705 Stock options issued and outstanding 9,749,498 6,203,020 Unvested restricted stock units 586,800 197,580 Total common stock reserved 12,375,439 9,272,305

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Summary of Stock-Based Compensation Expense	Total stock-based compensation expense recognized was as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Research and development $ 2,545 $ 1,745 $ 7,132 $ 5,319 General and administrative 3,015 2,446 8,216 7,557 Total stock-based compensation $ 5,560 $ 4,191 $ 15,348 $ 12,876
Summary of Stock Option Activity	Stock Options A summary of stock option activity for the nine months ended September 30, 2023 is set forth below: Number of Weighted Weighted- Aggregate Outstanding, December 31, 2022 6,203,020 $ 14.44 8.4 $ 780 Options granted 4,167,242 $ 5.48 Options exercised ( 946 ) $ 4.76 Options forfeited or cancelled ( 619,818 ) $ 12.35 Outstanding, September 30, 2023 9,749,498 $ 10.74 8.4 $ — Options exercisable, September 30, 2023 3,602,027 $ 13.87 7.6 $ — Vested and expected to vest, September 30, 2023 9,749,498 $ 10.74 8.4 $ —
Schedule of Assumptions to Estimate Fair Value of Stock Options Using Black-Scholes Option Pricing Model	The assumptions used in the Black Scholes Model to calculate stock-based compensation are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Fair value of common stock $ 1.37 - $ 3.38 $ 14.16 - $ 16.89 $ 1.37 - $ 9.15 $ 11.49 - $ 19.97 Expected term (years) 5.5 - 6.1 6.0 - 6.1 5.5 - 6.1 5.5 - 6.1 Volatility 84.7 % - 87.3 % 79.5 % - 80.7 % 83.3 % - 87.3 % 77.4 % - 80.7 % Risk free rates 4.1 % - 4.6 % 2.7 % - 4.0 % 3.5 % - 4.6 % 1.6 % - 4.0 % Dividend rate 0.0 % 0.0 % 0.0 % 0.0 %
Summary of Restricted Stock Unit Activity	The summary of RSU activity and related information for the nine months ended September 30, 2023 is set forth below: Number of Units Outstanding Weighted Average Outstanding, December 31, 2022 197,580 $ 7.8 RSUs granted 513,700 $ 7.6 RSUs vested ( 69,955 ) $ 7.6 RSUs forfeited ( 54,525 ) $ 7.2 Outstanding, September 30, 2023 586,800 $ 7.8

Net Loss per Share (Tables)

Net Loss per Share (Tables)	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders	The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share data): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Net loss - basic and diluted $ ( 49,885 ) $ ( 21,996 ) $ ( 113,169 ) $ ( 39,915 ) Weighted-average shares used in computing net loss per share, basic and diluted 42,980,641 41,642,815 43,001,901 40,547,792 Net loss per share, basic and diluted ( 1.16 ) ( 0.53 ) ( 2.63 ) ( 0.98 )
Schedule of Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss Per Share	The following outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share for the period presented because including them would have been antidilutive: As of September 30, 2023 2022 Options to purchase common stock 9,749,498 5,862,935 Unvested restricted stock units 586,800 318,160 Total 10,336,298 6,181,095

Organization and Nature of the

Organization and Nature of the Business - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	9 Months Ended
	Aug. 31, 2022	Mar. 12, 2021	Nov. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Schedule Of Equity Method Investments [Line Items]
Aggregate gross proceeds				$ 0	$ 43,360
Accumulated deficit				(351,283)		$ (238,114)
Adicet Therapeutics [Member]
Schedule Of Equity Method Investments [Line Items]
Accumulated deficit				$ 351,300
2021 Sales Agreement
Schedule Of Equity Method Investments [Line Items]
Aggregate number of shares sold	2,611,723
Sale of Stock, Price Per Share	$ 17.23
Sales agent commissions and expenses	$ 43,400
Common Stock not sold			$ 30,000
Additional Common Stock not sold			70,000
Aggregate gross proceeds			$ 100,000
Maximum | 2021 Sales Agreement
Schedule Of Equity Method Investments [Line Items]
Aggregate gross proceeds		$ 75,000

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets		$ 134,349	$ 75,701
Fair Value, Inputs, Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets		134,349	75,701
Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets		0	0
Fair Value, Inputs, Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets		0	0
Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets	[1],[2]	134,349
Treasury Securities | Fair Value, Inputs, Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets	[1],[2]	134,349
Treasury Securities | Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets	[1],[2]	0
Treasury Securities | Fair Value, Inputs, Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets	[1],[2]	$ 0
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets	[1],[3]		75,701
Money Market Funds | Fair Value, Inputs, Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets	[1],[3]		75,701
Money Market Funds | Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets	[1],[3]		0
Money Market Funds | Fair Value, Inputs, Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value of assets	[1],[3]		$ 0
[1] Included in cash and cash equivalents in the consolidated balance sheets. Treasury securities are included within Level 1 of the fair value hierarchy because they are actively traded and valued using quoted market prices. Money market funds are included within Level 1 of the fair value hierarchy because they are valued using quoted market prices.

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets - Summary of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid software subscription and licensing fees	$ 618	$ 529
Prepaid maintenance	555	295
Prepaid insurance	463	1,251
Prepayments to CROs and CDMOs	295	492
Prepaid lab supplies	221	0
Prepaid property taxes	76	61
Interest receivable	20	435
Other prepaid expenses and current assets	378	319
Total prepaid expenses and other current assets	$ 2,626	$ 3,382

Property and Equipment, Net - S

Property and Equipment, Net - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]	Leasehold Improvements
Total property and equipment	$ 41,435	$ 37,463
Less: Accumulated depreciation and amortization	(13,162)	(8,753)
Property and equipment, net	28,273	28,710
Laboratory Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	$ 12,863	7,503
Useful life (in years)	3 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment	$ 26,617	19,959
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Total property and equipment	$ 951	184
Useful life (in years)	3 years
Construction In Progress
Property Plant And Equipment [Line Items]
Total property and equipment	$ 473	9,292
Computer Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	$ 178	172
Useful life (in years)	3 years
Software
Property Plant And Equipment [Line Items]
Total property and equipment	$ 353	$ 353
Useful life (in years)	3 years

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Property, Plant and Equipment [Abstract]
Changes In Construction In Progress			$ 8,800
Remaining amount of construction in progress	$ 500		500
Depreciation and amortization expense	$ 1,600	$ 800	$ 4,409	$ 1,516

Accrued and Other Current Lia_3

Accrued and Other Current Liabilities - Summary of Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued compensation	$ 5,713	$ 5,703
Accrued CDMO costs	5,471	4,390
Accrued CRO costs	134	657
Accrued professional services	626	1,356
Accrued other research and development expenses	599	674
Accrued other liabilities	31	31
Total accrued and other liabilities	$ 12,574	$ 12,811

Term Loan - Additional Informat

Term Loan - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2023	May 30, 2023
Class Of Warrant Or Right [Line Items]
Available under the Loan Agreement	$ 12.7
Pacific western bank [Member]
Class Of Warrant Or Right [Line Items]
Total loan accounts outside		$ 2.5
Demand Deposit Accounts		35
Combined balances in demand deposit accounts	$ 200
Term Loan cash maintain		$ 35

Third Party Agreements - Additi

Third Party Agreements - Additional Information (Details) - USD ($) $ in Millions		9 Months Ended
	Jan. 28, 2022	Sep. 30, 2023
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development in process 1		$ 1
License agreement termination description		twelve (12) years
Regeneron Pharmaceuticals, Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized		$ 5
Exercise Fee Paid	$ 20	20
Licence agreement additional revenue recognised		25
Non refundable upfront payment received		25
Additional payment for research funding received		20
Regeneron Pharmaceuticals, Inc. | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Licence agreement additional amount payable of option exercise fees		$ 80

Third Party Agreements - Summar

Third Party Agreements - Summary of Change in Company's Contract Liabilities (Details) - Contract Liability - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Balance at beginning of period	$ 0	$ 4,805
Additions (Deductions) (1)	0	(4,805)	[1]
Balance at end of period	$ 0	$ 0
[1] Deductions to contract liabilities relate to deferred revenue recognized as revenue during the reporting period.

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) $ in Thousands		3 Months Ended	9 Months Ended
	Jan. 09, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 01, 2023 USD ($)	Jul. 19, 2021 ft²
Long Term Purchase Commitment [Line Items]
Area of sublease | ft²					9,501
Operating lease cost		$ 1,139	$ 3,300
Short-term lease cost		49	100
Sublease income		$ 179	500
Operating lease payments			$ 1,800
Westport Office Park, LLC [Member]
Long Term Purchase Commitment [Line Items]
Tenant improvements	$ 3,000
Debt instrument, basis spread on variable rate	8%
Letters of credit				$ 2,100

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Sublease Income (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2023	$ 177
2024	722
2025	736
2026	438
Total	$ 2,073

Commitments and Contingencies_3

Commitments and Contingencies - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]
2023	$ 1,241
2024	5,015
2025	4,662
2026	4,009
2027 and thereafter	12,090
Total undiscounted lease payments	27,017
Less: imputed interest	5,220
Total operating lease liability	21,797
Less: current portion	(3,128)	$ (2,492)
Operating lease liability, net of current portion	$ 18,669	$ 18,531

Commitments and Contingencies_4

Commitments and Contingencies - Summary of Lease Costs and Other Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 1,139	$ 3,300
Short-term lease cost	49	100
Sublease Income	(179)	$ (500)
Total lease cost	1,010
Operating cash flows used for lease liabilities	$ 773
Weighted-average remaining lease term - operating leases	5 years 10 months 24 days	5 years 10 months 24 days
Weighted-average discount rate - operating leases	7%	7%

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Class Of Stock [Line Items]
Common stock, shares authorized	150,000,000	150,000,000
Dividends Payable	$ 0
Common stock shares issued, par value	$ 0.0001	$ 0.0001

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Number of Shares of Common Stock Reserved for Future Issuance (Details) - shares	Sep. 30, 2023	Dec. 31, 2022
Class Of Stock [Line Items]
Number of shares of common stock reserved for future issuance	12,375,439	9,272,305
Unvested Restricted Stock Units
Class Of Stock [Line Items]
Number of shares of common stock reserved for future issuance	586,800	197,580
Stock Options Available for Future Grant
Class Of Stock [Line Items]
Number of shares of common stock reserved for future issuance	2,039,141	2,871,705
Options Issued and Outstanding
Class Of Stock [Line Items]
Number of shares of common stock reserved for future issuance	9,749,498	6,203,020

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of 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 [Line Items]
Total stock-based compensation expense	$ 5,560	$ 4,191	$ 15,348	$ 12,876
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	2,545	1,745	7,132	5,319
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 3,015	$ 2,446	$ 8,216	$ 7,557

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Number of Shares Underlying Outstanding Options, Beginning balance	6,203,020
Number of Shares Underlying Outstanding Options, Options granted	4,167,242
Number of Shares Underlying Outstanding Options, Options exercised	(946)
Number of Shares Underlying Outstanding Options, Options forfeited or cancelled	(619,818)
Number of Shares Underlying Outstanding Options, Ending balance	9,749,498	6,203,020
Number of Shares Underlying Outstanding Options exercisable	3,602,027
Number of Shares Underlying Outstanding Options, Vested and expected to vest	9,749,498
Weighted-Average Exercise Price, Outstanding beginning	$ 14.44
Weighted-Average Exercise Price, Options granted	5.48
Weighted-Average Exercise Price, Options exercised	4.76
Weighted-Average Exercise Price, Options forfeited or cancelled	12.35
Weighted-Average Exercise Price, Outstanding ending	10.74	$ 14.44
Weighted-Average Exercise Price, Options exercisable	13.87
Weighted-Average Exercise Price, Vested and expected to vest	$ 10.74
Weighted-Average Remaining Contract Term, Outstanding	8 years 4 months 24 days	8 years 4 months 24 days
Weighted-Average Remaining Contract Term, Options exercisable	7 years 7 months 6 days
Weighted-Average Remaining Contract Term, Vested and expected to vest	8 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 0	$ 780
Aggregate Intrinsic Value, Options exercisable	0
Aggregate Intrinsic Value, Vested and expected to vest	$ 0

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Aug. 08, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate gross proceeds				$ 0	$ 43,360
RSUs granted (includes PSUs)				4,167,242
Expense related to options granted		$ 5,560	$ 4,191	$ 15,348	$ 12,876
Weighted-Average Exercise Price, Options exercised				$ 4.76
Black-Scholes option-pricing model [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-Based Payment Arrangement, Incremental Cost, Amount recognized over the remaining vesting period of the repriced options		$ 400		$ 4,200
Share-Based Payment Arrangement, Plan Modification, Incremental Cost	$ 4,600
2015 Stock Incentive Plan Member
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Available for Grant, Options granted	(6,431,077)
Inducement Grant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance		1,418,042		1,418,042
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs Vested				69,955
Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Exercise Price	$ 2.14
Weighted-Average Grant Date Fair Value,Vested				$ 7.6

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Assumptions to Estimate Fair Value of Stock Options Using Black-Scholes Option Pricing Model (Details) - $ / shares	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 [Line Items]
Expected volatility, minimum	84.70%	79.50%	83.30%	77.40%
Expected volatility, maximum	87.30%	80.70%	87.30%	80.70%
Risk free rates, minimum	4.10%	2.70%	3.50%	1.60%
Risk free rates, maximum	4.60%	4%	4.60%	4%
Dividend rate	0%	0%	0%	0%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of common stock	$ 1.37	$ 14.16	$ 1.37	$ 11.49
Expected term	5 years 6 months	6 years	5 years 6 months	5 years 6 months
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of common stock	$ 3.38	$ 16.89	$ 9.15	$ 19.97
Expected term	6 years 1 month 6 days	6 years 1 month 6 days	6 years 1 month 6 days	6 years 1 month 6 days

Stock-based Compensation - Su_3

Stock-based Compensation - Summary of Restricted Stock Unit Activity (Details) - RSUs [Member]	9 Months Ended
	Sep. 30, 2023 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding, December 31, 2022 | shares	197,580
RSUs granted | shares	513,700
RSUs Vested | shares	(69,955)
RSUs forfeited | shares	(54,525)
Outstanding, March 31, 2023 | shares	586,800
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-Average Grant Date Fair Value, Beginning | $ / shares	$ 7.8
Weighted-Average Grant Date Fair Value, Granted | $ / shares	7.6
Weighted-Average Grant Date Fair Value,Vested | $ / shares	7.6
Weighted-Average Grant Date Fair Value, Forfeited | $ / shares	7.2
Weighted-Average Grant Date Fair Value, Ending | $ / shares	$ 7.8

Net Loss per Share - Additional

Net Loss per Share - Additional Information (Details) - shares	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	10,336,298	6,181,095
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	9,749,498	5,862,935
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	586,800	318,160

Net Loss per Share - Schedule o

Net Loss per Share - Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net loss - basic and diluted	$ (49,885)	$ (21,996)	$ (113,169)	$ (39,915)
Weighted-average shares used in computing net loss per share, basic and diluted	42,980,641	41,642,815	43,001,901	40,547,792
Net loss per share attributable to common stockholders, basic	$ (1.16)	$ (0.53)	$ (2.63)	$ (0.98)
Net loss per share attributable to common stockholders, diluted	$ (1.16)	$ (0.53)	$ (2.63)	$ (0.98)

Net Loss per Share - Schedule_2

Net Loss per Share - Schedule of Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Details) - shares	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	10,336,298	6,181,095
Options To Purchase Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	9,749,498	5,862,935
Unvested Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	586,800	318,160

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Taxes Disclosure [Line Items]
Income tax provision	$ 0	$ 0	$ 0	$ 0
COVID-19
Income Taxes Disclosure [Line Items]
Income tax provision			$ 0	$ 0

Related Party - Additional Info

Related Party - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Related Party Transaction [Line Items]
Owned common stock	43,107,921		42,954,820
Regeneron Pharmaceuticals, Inc.
Related Party Transaction [Line Items]
Owned common stock	883,568
Revenue from related party	$ 0	$ 0

Goodwill Impairment - Additiona

Goodwill Impairment - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Goodwill [Line Items]
Stock price declined	44%
Goodwill impairment charge	$ 19.5	$ 0

Subsequent Events (Additional I

Subsequent Events (Additional Information) (Details)	Sep. 30, 2023 shares
Subsequent Event [Line Items]
Number of Shares Underlying Outstanding Options, Vested and Unvested	9,749,498