Artiva Biotherapeutics, Inc. Common Stock (ARTV) 10-Q 12 Nov 24 2024 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2024	Oct. 31, 2024
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-42179
Entity Registrant Name	Artiva Biotherapeutics, Inc.
Entity Central Index Key	0001817241
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	83-3614316
Entity Address, Address Line One	5505 Morehouse Drive
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92121
City Area Code	858
Local Phone Number	267-4467
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	ARTV
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Interactive Data Current	Yes
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		24,289,328

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 55,881	$ 53,504
Short-term investments	90,750	23,467
Accounts receivable (including related party amounts of $569 and $569, respectively)	569	1,034
Other receivables (including related party amounts of $14 and $607, respectively)	132	724
Prepaid expenses and other current assets	3,233	1,092
Total current assets	150,565	79,821
Restricted cash	258	258
Property and equipment, net	6,857	8,096
Operating lease right-of-use assets	14,376	16,547
Financing lease right-of-use asset	276
Long-term investments	52,966
Other long-term assets	298	392
Total assets	225,596	105,114
Current liabilities:
Accounts payable (including related party amounts of $304 and $199, respectively)	1,215	614
Accrued expenses (including related party amounts of $1,307 and $2,161, respectively)	8,344	8,017
Current portion of operating lease liabilities	3,614	3,596
Current portion of financing lease liability	119
Total current liabilities	13,292	12,227
Operating lease liabilities, net of current portion	11,160	13,316
Financing lease liability, net of current portion	75
Simple agreements for future equity ("SAFEs") (including related party amounts of $0 and $20,315, respectively)		25,100
Other non-current liabilities	73	73
Total liabilities	24,600	50,716
Commitments and contingencies (Note 11)
Stockholders' equity (deficit):
Preferred stock, $0.0001 par value; 10,000,000 and zero shares authorized at September 30, 2024 and December 31, 2023 respectively; zero shares issued and outstanding as of September 30, 2024 and December 31, 2023
Common stock, $0.0001 par value; 700,000,000 and 38,998,588 shares authorized at September 30, 2024 and December 31, 2023, respectively; 24,287,144 and 809,758 shares issued and outstanding at September 30, 2024 and December 31, 2023	3
Additional paid-in capital	431,244	18,988
Accumulated other comprehensive income	338	308
Accumulated deficit	(230,589)	(181,311)
Total stockholders' equity (deficit)	200,996	(162,015)
Total liabilities, convertible preferred stock and stockholders' equity (deficit)	$ 225,596	105,114
Series A convertible preferred stock [Member]
Current liabilities:
Convertible preferred stock		96,767
Series B convertible preferred stock [Member]
Current liabilities:
Convertible preferred stock		$ 119,646

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Accounts receivable	$ 569	$ 1,034
Other receivables	132	724
Accounts payable	1,215	614
Accrued expenses	$ 8,344	8,017
Simple agreements for future equity		25,100
Common stock shares issued	424,000
Related party [Member]
Accounts receivable	$ 569	569
Other receivables	14	607
Accounts payable	304	199
Accrued expenses	1,307	2,161
Simple agreements for future equity	$ 0	$ 20,315
Common stock [Member]
Common stock par or stated value per share	$ 0.0001	$ 0.0001
Common stock shares authorized	700,000,000	38,998,588
Common stock shares issued	24,287,144	809,758
Common stock shares outstanding	24,287,144	809,758
Preferred stock [Member]
Preferred stock par or stated value per share	$ 0.0001	$ 0.0001
Preferred stock shares authorized	10,000,000	0
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0
Series A convertible preferred stock [Member]
Temporary equity par or stated value per share	$ 0.0001	$ 0.0001
Temporary equity shares authorized	0	16,110,463
Temporary equity shares issued	0	3,673,148
Temporary equity shares outstanding	0	3,673,148
Temporary equity liquidation preference	$ 0	$ 80,552
Series B convertible preferred stock [Member]
Temporary equity par or stated value per share	$ 0.0001	$ 0.0001
Temporary equity shares authorized	0	10,909,091
Temporary equity shares issued	0	2,487,237
Temporary equity shares outstanding	0	2,487,237
Temporary equity liquidation preference	$ 0	$ 120,000

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue:
Collaboration revenue		$ 26,656		$ 31,142
License and development support revenue (including related party amounts of $0, $0, $251 and $0, respectively)			$ 251
Total revenue		26,656	251	31,142
Operating Expenses [Abstract]
Research and development (including related party amounts of $1,342, $1,525, $2,802 and $3,335, respectively)	$ 13,524	13,065	37,011	39,098
General and administrative	4,811	2,780	12,255	10,745
Total operating expenses	18,335	15,845	49,266	49,843
Income (loss) from operations	(18,335)	10,811	(49,015)	(18,701)
Other income (expense), net:
Interest income	1,846	418	3,172	1,952
Change in fair value of SAFEs (including related party amounts of $799, $0, $2,112 and $0, respectively)	(977)		(3,597)
Other income (expense), net	(6)	50	162	27
Total other income (expense), net	863	468	(263)	1,979
Net income (loss)	$ (17,472)	$ 11,279	$ (49,278)	$ (16,722)
Net income (loss) per share - basic	$ (0.92)	$ 13.98	$ (7.16)	$ (20.89)
Net income (loss) per share - diluted	$ (0.92)	$ 1.62	$ (7.16)	$ (20.89)
Weighted average common shares outstanding - basic	18,896,829	806,714	6,883,271	800,541
Weighted average common shares outstanding - diluted	18,896,829	6,967,099	6,883,271	800,541
Other comprehensive income (loss):
Unrealized gain on investments	$ 217	$ 144	$ 30	$ 271
Comprehensive income (loss)	$ (17,255)	$ 11,423	$ (49,248)	$ (16,451)

Condensed Statements of Opera_2

Condensed Statements of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue not from contract with customer			$ 251
Research and development including related party	$ 13,524	$ 13,065	37,011	$ 39,098
Change in fair value of SAFEs including related party	977		3,597
Related party [Member]
Revenue not from contract with customer	0	0	251	0
Research and development including related party	1,342	1,525	2,802	3,335
Change in fair value of SAFEs including related party	$ 799	$ 0	$ 2,911	$ 0

Condensed Statements of Convert

Condensed Statements of Convertible Preferred Stock and Stockholders' Deficit - USD ($) $ in Thousands	Total	SERIES A CONVERTIBLE PREFERRED STOCK [Member]	SERIES B CONVERTIBLE PREFERRED STOCK [Member]	COMMON STOCK [Member]	ADDITIONAL PAID-IN CAPITAL [Member]	ACCUMULATED OTHER COMPREHENSIVE INCOME [Member]	ACCUMULATED DEFICIT [Member]
Beginning balance, Temporary equity (in Shares) at Dec. 31, 2022		3,673,148	2,487,237
Beginning balance, Temporary equity at Dec. 31, 2022		$ 96,767	$ 119,646
Beginning balance (in Shares) at Dec. 31, 2022				792,991
Beginning balance at Dec. 31, 2022	$ (140,696)				$ 11,895		$ (152,591)
Vesting of shares of common stock subject to repurchase, including early exercise (in Shares)				1,425
Vesting of shares of common stock subject to repurchase, including early exercise	7				7
Stock-based compensation expense	1,832				1,832
Net Income (Loss)	(16,717)						(16,717)
Ending balance, Temporary equity (in Shares) at Mar. 31, 2023		3,673,148	2,487,237
Ending balance, Temporary equity at Mar. 31, 2023		$ 96,767	$ 119,646
Ending balance (in Shares) at Mar. 31, 2023				794,416
Ending balance at Mar. 31, 2023	(155,574)				13,734		(169,308)
Beginning balance, Temporary equity (in Shares) at Dec. 31, 2022		3,673,148	2,487,237
Beginning balance, Temporary equity at Dec. 31, 2022		$ 96,767	$ 119,646
Beginning balance (in Shares) at Dec. 31, 2022				792,991
Beginning balance at Dec. 31, 2022	(140,696)				11,895		(152,591)
Unrealized gain (loss) on investments	271
Net Income (Loss)	(16,722)
Ending balance, Temporary equity (in Shares) at Sep. 30, 2023		3,673,148	2,487,237
Ending balance, Temporary equity at Sep. 30, 2023		$ 96,767	$ 119,646
Ending balance (in Shares) at Sep. 30, 2023				808,334
Ending balance at Sep. 30, 2023	(151,454)				17,588	$ 271	(169,313)
Beginning balance, Temporary equity (in Shares) at Mar. 31, 2023		3,673,148	2,487,237
Beginning balance, Temporary equity at Mar. 31, 2023		$ 96,767	$ 119,646
Beginning balance (in Shares) at Mar. 31, 2023				794,416
Beginning balance at Mar. 31, 2023	(155,574)				13,734		(169,308)
Exercise of stock options (in Shares)				1,948
Exercise of stock options	10				10
Vesting of shares of common stock subject to repurchase, including early exercise (in Shares)				8,835
Vesting of shares of common stock subject to repurchase, including early exercise	8				8
Stock-based compensation expense	2,458				2,458
Unrealized gain (loss) on investments	127					127
Net Income (Loss)	(11,284)						(11,284)
Ending balance, Temporary equity (in Shares) at Jun. 30, 2023		3,673,148	2,487,237
Ending balance, Temporary equity at Jun. 30, 2023		$ 96,767	$ 119,646
Ending balance (in Shares) at Jun. 30, 2023				805,199
Ending balance at Jun. 30, 2023	(164,255)				16,210	127	(180,592)
Vesting of shares of common stock subject to repurchase, including early exercise (in Shares)				3,135
Vesting of shares of common stock subject to repurchase, including early exercise	7				7
Stock-based compensation expense	1,371				1,371
Unrealized gain (loss) on investments	144					144
Net Income (Loss)	11,279						11,279
Ending balance, Temporary equity (in Shares) at Sep. 30, 2023		3,673,148	2,487,237
Ending balance, Temporary equity at Sep. 30, 2023		$ 96,767	$ 119,646
Ending balance (in Shares) at Sep. 30, 2023				808,334
Ending balance at Sep. 30, 2023	(151,454)				17,588	271	(169,313)
Beginning balance, Temporary equity (in Shares) at Dec. 31, 2023		3,673,148	2,487,237
Beginning balance, Temporary equity at Dec. 31, 2023		$ 96,767	$ 119,646
Beginning balance (in Shares) at Dec. 31, 2023				809,758
Beginning balance at Dec. 31, 2023	(162,015)				18,988	308	(181,311)
Stock-based compensation expense investments	1,406				1,406
Unrealized gain (loss) on investments	(101)					(101)
Net Income (Loss)	(13,963)						(13,963)
Ending balance, Temporary equity (in Shares) at Mar. 31, 2024		3,673,148	2,487,237
Ending balance, Temporary equity at Mar. 31, 2024		$ 96,767	$ 119,646
Ending balance (in Shares) at Mar. 31, 2024				809,758
Ending balance at Mar. 31, 2024	(174,673)				20,394	207	(195,274)
Beginning balance, Temporary equity (in Shares) at Dec. 31, 2023		3,673,148	2,487,237
Beginning balance, Temporary equity at Dec. 31, 2023		$ 96,767	$ 119,646
Beginning balance (in Shares) at Dec. 31, 2023				809,758
Beginning balance at Dec. 31, 2023	(162,015)				18,988	308	(181,311)
Unrealized gain (loss) on investments	30
Net Income (Loss)	(49,278)
Ending balance, Temporary equity (in Shares) at Sep. 30, 2024			0
Ending balance (in Shares) at Sep. 30, 2024				24,287,144
Ending balance at Sep. 30, 2024	200,996			$ 3	431,244	338	(230,589)
Beginning balance, Temporary equity (in Shares) at Mar. 31, 2024		3,673,148	2,487,237
Beginning balance, Temporary equity at Mar. 31, 2024		$ 96,767	$ 119,646
Beginning balance (in Shares) at Mar. 31, 2024				809,758
Beginning balance at Mar. 31, 2024	(174,673)				20,394	207	(195,274)
Exercise of stock options (in Shares)				4,444
Exercise of stock options	22				22
Stock-based compensation expense	1,483				1,483
Unrealized gain (loss) on investments	(86)					(86)
Net Income (Loss)	(17,843)						(17,843)
Ending balance, Temporary equity (in Shares) at Jun. 30, 2024		3,673,148	2,487,237
Ending balance, Temporary equity at Jun. 30, 2024		$ 96,767	$ 119,646
Ending balance (in Shares) at Jun. 30, 2024				814,202
Ending balance at Jun. 30, 2024	(191,097)				21,899	121	(213,117)
Conversion of preferred stock into common stock upon completion of initial public offering (IPO) (in Shares)		(3,673,148)	(2,487,237)
Conversion of preferred stock into common stock upon completion of initial public offering (IPO)		$ (96,767)	$ (119,646)
Conversion of preferred stock into common stock upon completion of initial public offering (IPO) (in Shares)				6,160,385
Conversion of preferred stock into common stock upon completion of initial public offering (IPO)	216,413			$ 1	216,412
Exercise of stock options (in Shares)				1,139
Exercise of stock options	6				6
Issuance of common shares in connection with IPO, net of offering costs (in Shares)				14,920,000
Issuance of common shares in connection with IPO, net of offering costs	162,325			$ 2	162,323
Issuance of common shares upon the conversion of SAFE notes (in Shares)				2,391,418
Issuance of common shares upon the conversion of SAFE notes	28,697				28,697
Stock-based compensation expense	1,907				1,907
Unrealized gain (loss) on investments	217					217
Net Income (Loss)	(17,472)						(17,472)
Ending balance, Temporary equity (in Shares) at Sep. 30, 2024			0
Ending balance (in Shares) at Sep. 30, 2024				24,287,144
Ending balance at Sep. 30, 2024	$ 200,996			$ 3	$ 431,244	$ 338	$ (230,589)

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Operating activities:
Net income (loss)	$ (49,278)	$ (16,722)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation and amortization	1,817	1,672
Stock-based compensation	4,796	5,661
Change in fair value of SAFEs (including related party amounts of $2,911 and $0, respectively)	3,597
Accretion of discounts and amortization of premiums on investments, net	(1,300)	(173)
Changes in operating assets and liabilities:
Accounts receivable	465	(1,612)
Other receivables (including related party amounts of $(593) and $(1,040), respectively)	592	(1,338)
Prepaid expenses and other current assets	(2,141)	298
Other long-term assets	94	94
Accounts payable (including related party amounts of $104 and $678, respectively)	601	1,514
Accrued expenses (including related party amounts of $(854) and $345, respectively)	333	(1,055)
Operating lease right-of-use asset and lease liabilities	42	117
Deferred revenue		(25,211)
Net cash used in operating activities	(40,382)	(36,755)
Investing activities:
Purchases of property and equipment	(578)	(2,622)
Purchases of investments	(161,319)	(34,685)
Maturities of investments	42,400	14,000
Net cash used in investing activities	(119,497)	(23,307)
Financing activities:
Proceeds from issuance of common stock, net of commissions	166,507
Proceeds from issuance of simple agreements for future equity		23,431
Proceeds from exercise of stock options	28	10
Payments on finance leases	(116)
Cash paid in connection with IPO offering costs	(4,163)
Repurchase of restricted stock		(12)
Net cash provided by financing activities	162,256	23,429
Net increase (decrease) in cash, cash equivalents and restricted cash	2,377	(36,633)
Cash, cash equivalents and restricted cash at beginning of period	53,762	102,776
Cash, cash equivalents and restricted cash at end of period	56,139	66,143
Reconciliation of cash, cash equivalents and restricted cash to the balance sheet:
Cash and cash equivalents	55,881	65,885
Restricted cash	258	258
Total cash, cash equivalents and restricted cash	56,139	66,143
Supplemental disclosures of noncash activities:
Property and equipment purchases in accounts payable and accrued liabilities	10	617
Deferred offering costs in accounts payable and accrued liabilities	19
Conversion of SAFE notes to common stock	28,697
Conversion of preferred stock to common stock	216,413
Non-cash additions to financing leases	$ 241

Condensed Statements of Cash _2

Condensed Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Change in fair value of SAFEs including related party	$ 3,597
Other receivables including related party	592	(1,338)
Accounts payable including related party	601	1,514
Accrued expenses including related party	333	(1,055)
Related party [Member]
Change in fair value of SAFEs including related party	2,911	0
Other receivables including related party	(593)	(1,040)
Accounts payable including related party	104	678
Accrued expenses including related party	$ (854)	$ 345

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ (17,472)	$ (17,843)	$ (13,963)	$ 11,279	$ (11,284)	$ (16,717)	$ (49,278)	$ (16,722)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Sep. 30, 2024 shares
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Trading Arrangements During the last fiscal quarter, our directors and officers (as defined in Rule 16a-1(f) under the Exchange Act) adopted or terminated the contracts, instructions or written plans for the purchase or sale of the Company’s securities set forth in the table below: Type of Trading Arrangement Name and Position Action Adoption/ Termination Date Rule 10b5-1* Non- Rule 10b5-1** Total Shares of Common Stock to be Sold Expiration Date Fred Aslan, M.D. ( President, Chief Executive Officer and Director ) Adoption July 23, 2024 X 471,558 December 31, 2026 Neha Krishnamohan ( Chief Financial Officer and Executive Vice President of Corporate Development ) Adoption July 23, 2024 X 12,768 June 2, 2027 Christopher Horan ( Chief Technical Operations Officer ) Adoption July 23, 2024 X 44,200 April 15, 2026 Thorsten Graef, M.D., Ph.D. ( Chief Medical Officer ) Adoption July 23, 2024 X 67,021 April 15, 2026 Jennifer Bush ( Chief Operating Officer, Chief Legal Officer, Corporate Secretary and Compliance Officer ) Adoption July 23, 2024 X 28,000 May 31, 2026 Heather Raymon, Ph.D. ( Senior Vice President of Research and Early Development ) Adoption July 23, 2024 X 25,434 April 15, 2026 * Contract, instruction or written plan intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act. ** “Non-Rule 10b5-1 trading arrangement” as defined in Item 408(c) of Regulation S-K under the Exchange Act. Our directors and officers entered into lock-up agreements in connection with the IPO and they are not permitted to transfer, sell or otherwise dispose of securities under such plans during the lock-up period or pursuant to any exceptions set form in the lock-up agreements.
Fred Aslan M.D [Member]
Trading Arrangements, by Individual
Name	Fred Aslan, M.D.
Title	President, Chief Executive Officer and Director
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	July 23, 2024
Expiration Date	December 31, 2026
Arrangement Duration	892 days
Aggregate Available	471,558
Neha Krishnamohan [Member]
Trading Arrangements, by Individual
Name	Neha Krishnamohan
Title	Chief Financial Officer and Executive Vice President of Corporate Development
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	July 23, 2024
Expiration Date	June 2, 2027
Arrangement Duration	1045 days
Aggregate Available	12,768
Christopher Horan [Member]
Trading Arrangements, by Individual
Name	Christopher Horan
Title	Chief Technical Operations Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	July 23, 2024
Expiration Date	April 15, 2026
Arrangement Duration	632 days
Aggregate Available	44,200
Thorsten Graef M.D [Member]
Trading Arrangements, by Individual
Name	Thorsten Graef, M.D., Ph.D.
Title	Chief Medical Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	July 23, 2024
Expiration Date	April 15, 2026
Arrangement Duration	632 days
Aggregate Available	67,021
Jennifer Bush [Member]
Trading Arrangements, by Individual
Name	Jennifer Bush
Title	Chief Operating Officer, Chief Legal Officer, Corporate Secretary and Compliance Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	July 23, 2024
Expiration Date	May 31, 2026
Arrangement Duration	678 days
Aggregate Available	28,000
Heather Raymon Ph.D [Member]
Trading Arrangements, by Individual
Name	Heather Raymon, Ph.D.
Title	Senior Vice President of Research and Early Development
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	July 23, 2024
Expiration Date	April 15, 2026
Arrangement Duration	632 days
Aggregate Available	25,434

Organization, Liquidity and Bas

Organization, Liquidity and Basis of Presentation	9 Months Ended
	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Liquidity and Basis of Presentation	1. Organization, Liquidity and Basis of Presentation Organization Artiva Biotherapeutics, Inc. (the “Company”) was incorporated in the State of Delaware on February 14, 2019 . The Company is a biopharmaceutical company focused on developing off-the shelf, allogeneic, natural killer (“NK”) cell-based therapies that are effective, safe and accessible for patients with devastating autoimmune diseases and cancers. From its inception to September 30, 2024, the Company has devoted substantially all of its resources to organizing and staffing the Company, business planning, raising capital, establishing and engaging in collaborations, performing research and development, advancing and scaling up product candidate manufacturing, establishing cold chain delivery logistics, establishing and protecting its intellectual property portfolio, and providing general and administrative support for these activities. Reverse Stock Split On July 12, 2024, the Company effected a 1-for-4.386 reverse stock split of its common stock and convertible preferred stock. The par value and the authorized shares of the common stock and convertible preferred stock were not adjusted as a result of the reverse stock split. These accompanying condensed financial statements and notes to the condensed financial statements give retroactive effect to the reverse stock split for all periods presented. Initial Public Offering On July 22, 2024, the Company completed its Initial Public Offering (the “IPO”), pursuant to which it issued and sold 13,920,000 shares of common stock at a public offering price of $ 12.00 per share. The aggregate gross proceeds of the IPO were $ 167.0 million before underwriter discounts and commissions, fees, and expenses of $ 15.9 million, for net proceeds from the IPO of $ 151.1 million. On July 25, 2024, the underwriters partially exercised their 30-day option and purchased an additional 1,000,000 shares of the Company’s common stock at the IPO price, upon which the Company received additional gross proceeds of $ 12.0 million before commissions of $ 0.8 million, for net proceeds of approximately $ 11.2 million. The aggregate net proceeds of the IPO was $ 162.3 million (the “IPO Proceeds”). All underwriter discounts and commissions, fees, and expenses, including deferred offering costs have been charged to additional paid in capital as recorded against the gross proceeds. Liquidity The Company has incurred net losses and negative cash flows from operations since inception, has a significant accumulated deficit and expects to continue to incur net losses for the foreseeable future. The Company has never generated any revenue from product sales and does not expect to generate any revenues from product sales unless and until it successfully completes development of and obtains regulatory approval for its product candidates, which will not be for several years, if ever. The Company has an accumulated deficit of $ 230.6 million as of September 30, 2024. During the nine months ended September 30, 2024, the Company used $ 40.4 million of cash for operating activities. As of September 30, 2024, the Company has $ 199.6 million in cash, cash equivalents and investments. From inception through September 30, 2024 , the Company has raised aggregate gross proceeds of $ 401.4 million to fund operations, comprised primarily from proceeds received from the IPO, including proceeds from the underwriters partial exercise of their purchase option, issuances of convertible promissory notes, simple agreements for future equity (“SAFEs”) and private placements of convertible preferred stock. Since inception through September 30, 2024 , the Company has also received $ 39.9 million in upfront and reimbursable research service payments from Merck Sharp & Dohme Corp. (“Merck”). Management estimates that there is no substantial doubt about the Company’s ability to continue as a going concern for the one year period following the date that these unaudited condensed financial statements and accompanying notes were issued, as the Company’s existing cash, cash equivalents and investments will be sufficient to fund planned operations at least through the end of 2026. As such, the prior substantial doubt about the Company’s ability to continue as a going concern as discussed in the Company’s December 31, 2023 audited financial statements as included in the Company’s prospectus dated July 18, 2024 related to its IPO filed pursuant to Rule 424(b)(4) under the Securities Act of 1933, no longer exists. If the Company is unable to obtain additional funding before achieving sufficient profitability and positive cash flows from operations, if ever, the Company will be forced to delay, reduce or eliminate some or all of its research and development programs, which could adversely affect its business prospects, or the Company may be unable to continue operations. Although management continues to pursue plans to obtain additional funding before achieving sufficient profitability and positive cash flows from operations, 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. Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and pursuant to rules and regulations of the Securities Exchange Commission for interim financial information. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. These unaudited condensed financial statements include only normal and recurring adjustments that the Company believes are necessary to fairly state the Company’s financial position and the results of its operations and cash flows. The results for the three and nine months ended September 30, 2024 and 2023 are not necessarily indicative of the results expected for the full fiscal year or any subsequent interim period. The unaudited condensed balance sheet as of September 30, 2024 has been derived from the financial statements as of that date but does not include all disclosures required by GAAP for complete financial statements. As all of the disclosures required by GAAP for complete financial statements are not included herein, these condensed financial statements and the notes accompanying herein should be read in conjunction with the Company’s audited financial statements as of and for the year ended December 31, 2023 included in the Company’s prospectus dated July 18, 2024 related to its IPO filed pursuant to Rule 424(b)(4) under the Securities Act of 1933. Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) promulgated by the Financial Accounting Standards Board (“FASB”).

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The Company’s significant accounting policies are disclosed in the audited financial statements as of and for the year ended December 31, 2023, included in the Company’s prospectus dated July 18, 2024 related to its IPO filed pursuant to Rule 424(b)(4) under the Securities Act of 1933. Since the date of those financial statements, there have been no changes to its significant accounting policies, except where noted below. Use of Estimates The preparation of condensed financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed financial statements and the reported amounts of expenses during the reporting period. Accounting estimates and management judgments reflected in the condensed financial statements include: revenue recognized, the accrual of research and development expenses, common stock, stock-based compensation, SAFEs and operating lease liabilities. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may materially differ from these estimates and assumptions. Investments The Company holds investments in commercial paper, government and government agency bonds, and corporate bonds. The Company has classified its investment securities as current and non-current assets on the condensed balance sheets based on each security's contractual maturity date, and all investment securities are accounted for as available-for-sale because these investment securities are considered available for use in operations. The Company carries these securities at fair value and reports unrealized gains and losses as a separate component of accumulated other comprehensive income. The cost of debt securities is adjusted for amortization of purchase premiums and accretion of discounts to maturity. Such amortization and accretion are included in other income in the condensed statements of operations and comprehensive income (loss). Realized gains and losses on sales of securities are determined using the specific identification method and recorded in other income in the condensed statements of operations and comprehensive income (loss). As of September 30, 2024, and December 31, 2023 , accrued interest receivables on investments were $ 0.7 million and $ 0.1 million, respectively, and are included in prepaid expenses and other current assets in the condensed balance sheets. The Company does not measure an allowance for credit losses for accrued interest receivables. For the purposes of identifying and measuring an impairment, accrued interest is excluded from both the fair value and amortized cost basis of the investment. Uncollectible accrued interest receivables associated with an impaired debt security are reversed against interest income upon identification of the impairment. No accrued interest receivables were written off during the three and nine months ended September 30, 2024 and 2023 . Restricted Cash Restricted cash is comprised of cash that is restricted as to withdrawal or use under the terms of certain contractual agreements. Restricted cash as of September 30, 2024 and December 31, 2023 , was $ 0.3 million consisting of collateral for letters of credit related to the Company’s lease agreements and is included in non-current assets in the condensed balance sheets (see Note 11). Net Income (Loss) Per Share Basic net income (loss) per share is calculated by dividing the net income (loss) by the weighted-average number of common shares outstanding for the period. Diluted net income (loss) per share is computed by dividing the net income (loss) by the weighted-average number of shares of common stock and common stock equivalents outstanding for the period. Common stock equivalents are only included when their effect is dilutive. The Company’s potentially dilutive securities include shares of its convertible preferred stock, as well as outstanding stock options and restricted stock units under the Company’s equity incentive plan and have been excluded from the computation of diluted net loss per share, for all periods except the three months ended September 30, 2023, as they would be anti-dilutive to the net loss per share. The Company recorded net income for the three months ended September 30, 2023. The Company used the treasury stock method and if-converted method to determine the weighted-average number of shares of common stock equivalents outstanding for the three months ended September 30, 2023. The following table sets forth the computation of basic and diluted net income (loss) per share (in thousands, except share and per share data): THREE MONTHS ENDED NINE MONTHS ENDED SEPTEMBER 30, SEPTEMBER 30, SEPTEMBER 30, SEPTEMBER 30, Basic Net Income (Loss) per share Net income (loss) $ ( 17,472 ) $ 11,279 $ ( 49,278 ) $ ( 16,722 ) Weighted average common shares outstanding - basic 18,896,829 806,714 6,883,271 800,541 Net income (loss) per share - basic $ ( 0.92 ) $ 13.98 $ ( 7.16 ) $ ( 20.89 ) Diluted Net Income (Loss) per share Net income (loss) $ ( 17,472 ) $ 11,279 $ ( 49,278 ) $ ( 16,722 ) Weighted average common shares outstanding - basic 18,896,829 806,714 6,883,271 800,541 Weighted average effect of dilutive securities: Series A preferred stock — 3,673,148 — — Series B preferred stock — 2,487,237 — — Weighted average common shares outstanding - diluted 18,896,829 6,967,099 6,883,271 800,541 Net income (loss) per share - diluted $ ( 0.92 ) $ 1.62 $ ( 7.16 ) $ ( 20.89 ) The following table sets forth the outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because their inclusion would be anti-dilutive for the nine months ended September 30, 2024 and 2023: AS OF AS OF Convertible preferred stock — 6,160,385 Unvested restricted stock units 533,484 22,514 Options to purchase common stock 2,238,816 1,323,348 Total 2,772,300 7,506,247 Recently Adopted Accounting Standards In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”). ASU 2020-06 was issued to reduce the complexity associated with accounting for certain financial instruments with characteristics of liabilities and equity. ASU 2020-06 reduces the number of accounting models for convertible debt instruments and redeemable convertible preferred stock and improves the disclosures for convertible instruments and related earnings per share guidance. ASU 2020-06 also amends the guidance for the derivatives scope exception for contracts in an entity’s own equity and improves and amends the related earnings per share guidance. For public entities that qualify as a filer with the Securities and Exchange Commission, excluding entities eligible to be smaller reporting companies, ASU 2020-06 is effective for fiscal annual periods beginning after December 15, 2021, including interim periods within those fiscal years. For nonpublic entities, ASU 2020-06 is effective for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early adoption is permitted, but no earlier than fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. ASU 2020-06 must be adopted as of the beginning of a Company’s annual fiscal year. The Company adopted this standard on January 1, 2024 , and the adoption of the standard did not have a material impact on its financial statements. In November 2023, the FASB issued ASU 2023-07, Segment Reporting—Improvements to Reportable Segment Disclosures (“ASU 2023-07”). The update requires entities to disclose their significant segment expense categories and amounts for each reportable segment. Significance is assessed using both quantitative and qualitative factors depending on the facts and circumstances. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023, and interim periods in fiscal years beginning after December 15, 2024. The Company is currently evaluating the impact that this standard will have on the related disclosures in its financial statements. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures (“ASU 2023-09”). The update requires enhanced disclosures on income taxes paid, adds disaggregation of continuing operations before income taxes between foreign and domestic earnings and defines specific categories for the reconciliation of jurisdictional tax rate to effective tax rate. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024, and can be applied on a prospective basis. The Company is currently evaluating the impact that this standard will have on the related disclosures in its financial statements.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements The following table presents information about the Company’s financial assets and liabilities that are measured at fair value on a recurring basis and indicates their respective levels within the fair value hierarchy (in thousands): AS OF SEPTEMBER 30, 2024 CLASSIFICATION TOTAL LEVEL 1 LEVEL 2 LEVEL 3 Assets Money market funds Cash and cash equivalents $ 35,353 $ 35,353 $ — $ — Commercial paper Cash and cash equivalents 11,495 — 11,495 — Government bonds Cash and cash equivalents 6,281 — 6,281 — Commercial paper Short-term investments 73,180 — 73,180 — Government agency bonds Short-term investments 4,505 — 4,505 — Corporate bonds Short-term investments 13,065 — 13,065 — Government and government Long-term investments 45,142 — 45,142 — Corporate bonds Long-term investments 7,824 — 7,824 — Total assets $ 196,845 $ 35,353 $ 161,492 $ — AS OF DECEMBER 31, 2023 CLASSIFICATION TOTAL LEVEL 1 LEVEL 2 LEVEL 3 Assets Money market funds Cash and cash equivalents $ 28,517 $ 28,517 $ — $ — Commercial paper Short-term investments 2,090 — 2,090 — Government and government Short-term investments 19,982 — 19,982 — Corporate bonds Short-term investments 1,395 — 1,395 — Total assets $ 51,984 $ 28,517 $ 23,467 $ — Liabilities SAFEs Liabilities $ 25,100 $ — $ — $ 25,100 Total liabilities $ 25,100 $ — $ — $ 25,100 The carrying amounts of all cash and cash equivalents, accounts receivable, other receivable, prepaid and other current assets, accounts payable, and accrued expenses are considered to be representative of their respective fair values because of the short-term nature of those instruments. Short-Term and Long-Term Investments The Company’s assets with a fair value categorized as Level 2 within the fair value hierarchy consist of commercial paper, government and government agency bonds, and corporate bonds. These assets have been initially valued at the transaction price and subsequently valued at the end of each reporting period utilizing third-party pricing services. The pricing services utilize industry standard valuation models whereby all significant inputs, including benchmark yields, reported trades, broker/dealer quotes, issuer spreads, bids, offers, or other market-related data, are observable. Simple Agreements for Future Equity The estimated fair value of the SAFEs (see Note 7) is determined based on the aggregated, probability-weighted average of the outcomes of certain scenarios, including: (i) equity financing, with conversion of the SAFEs into a number of shares of convertible preferred stock at the lower of the post-money valuation cap price of $ 48.25 and the discount price (the lowest price of the standard convertible preferred stock sold in the equity financing multiplied by the specified discount rate of 85 %); (ii) liquidity event (change of control, direct listing, or an initial public offering,) with mandatory conversion to common stock at the lower of post-money valuation cap price of $ 48.25 and discount price (price of the common stock multiplied by the discount rate of 85 %); and (iii) dissolution event, with SAFE holders automatically entitled to receive cash payments equal to the purchase amount, prior to and in preference to any distribution of any assets or surplus funds to the holders of convertible preferred and common stock. On May 29, 2024, the Company executed an amendment to the SAFEs (the “SAFE Amendment”). The SAFE Amendment amended the definition of liquidity event to exclude an initial public offering and amended the definition of the discount price under an initial public offering to the lower of (a) the price per share of common stock sold to the public by the underwriters in the initial public offering multiplied by the discount rate of 85 % or (b) the post-money valuation cap price of $ 48.25 . The combined value of the probability-weighted average of those outcomes is then discounted back to each reporting period in which the SAFEs are outstanding, in each case based on a risk-adjusted discount rate estimated based on the implied interest rate using the changes in observed interest rates of corporate debt that the Company believes is appropriate for those probability-adjusted cash flows. Fair value measurements associated with SAFEs were determined based on significant inputs not observable in the market, which represent Level 3 measurements within the fair value hierarchy. Increases and decreases in the fair value of the SAFEs can result from updates to assumptions such as expected timing and probability of a qualified financing event, or changes in discount rates, among other assumptions. Based on management’s assessment of the valuation of the SAFEs, performed by the Company’s third-party valuation specialists, none of the changes in the fair value of those instruments were due to changes in the Company’s own credit risk for the reporting periods presented. Judgement is used in determining these assumptions as of the initial valuation date and at each subsequent reporting period. Changes or updates to assumptions could have a material impact on the reported fair value, and the change in fair value of SAFEs and the results of operations in any given period. In connection with the closing of the IPO, the Company’s outstanding convertible SAFE shares automatically converted into 2,391,418 shares of common stock. The following tables summarize the significant inputs not observable in the market upon which the fair value measurements associated with the SAFEs were determined: VALUATION TECHNIQUE UNOBSERVABLE INPUT AS OF DECEMBER 31, 2023 Liabilities SAFEs Scenario-based approach Probability weighting 15.0 % - 70.0 % Discount rate 20.1 % Remaining term to event (in years) 0.50 - 0.75 The following table summarizes the changes in fair value associated with Level 3 financial instruments held during the periods presented (in thousands): SAFEs Balance at December 31, 2023 $ 25,100 Changes in fair value of SAFEs 3,597 Conversion of SAFEs to common stock ( 28,697 ) Balance at September 30, 2024 $ —

Cash, Cash Equivalents and Inve

Cash, Cash Equivalents and Investments	9 Months Ended
	Sep. 30, 2024
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents and Investments	4. Cash, Cash Equivalents and Investments It is the Company’s policy to mitigate credit risk in its financial assets by maintaining a well-diversified portfolio that limits the amount of exposure as to maturity and investment type. The following table summarizes the Company’s cash and cash equivalents, short-term investments, and long-term investments for each of the periods presented (in thousands): AS OF SEPTEMBER 30, 2024 CLASSIFICATION MATURITY AMORTIZED GROSS GROSS FAIR Cash and money market funds Cash and cash equivalents Less than three months $ 38,105 $ — $ — $ 38,105 Commercial paper Cash and cash equivalents Less than three months 11,493 2 — 11,495 Government bonds Cash and cash equivalents Less than three months 6,258 23 — 6,281 Commercial paper Short-term investments 1 year or less 73,098 82 — 73,180 Government agency bonds Short-term investments 1 year or less 4,497 8 — 4,505 Corporate bonds Short-term investments 1 year or less 13,042 23 — 13,065 Government and government agency Long-term investments Greater than 1 year 44,955 187 — 45,142 Corporate bonds Long-term investments Greater than 1 year 7,811 13 — 7,824 Total cash and cash equivalents, short- $ 199,259 $ 338 $ — $ 199,597 AS OF DECEMBER 31, 2023 CLASSIFICATION MATURITY AMORTIZED GROSS GROSS FAIR Cash and money market funds Cash and cash equivalents Less than three months $ 53,504 $ — $ — $ 53,504 Commercial paper Short-term investments 1 year or less 2,048 42 — 2,090 Government and government agency Short-term investments 1 year or less 19,728 254 — 19,982 Corporate bonds Short-term investments 1 year or less 1,383 12 — 1,395 Total cash, cash equivalents and short- $ 76,663 $ 308 $ — $ 76,971 As of September 30, 2024 , the Company did no t have any investments with gross unrealized losses. The Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost basis. As of September 30, 2024 , no allowance for credit losses was recorded.

Property and Equipment, Net

Property and Equipment, Net	9 Months Ended
	Sep. 30, 2024
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	5. Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): AS OF SEPTEMBER 30, DECEMBER 31, Lab equipment $ 10,284 $ 9,760 Furniture and fixtures 872 871 Computers and software 616 607 Leasehold improvements 410 390 12,182 11,628 Less accumulated depreciation ( 5,325 ) ( 3,532 ) Total property and equipment, net $ 6,857 $ 8,096 The Company recognized $ 0.6 million and $ 1.8 million in depreciation expense for the three and nine months ended September 30, 2024 , respectively, and $ 0.6 million and $ 1.7 million in depreciation expense for the three and nine months ended September 30, 2023 , respectively.

Accrued Expenses

Accrued Expenses	9 Months Ended
	Sep. 30, 2024
Payables and Accruals [Abstract]
Accrued Expenses	6. Accrued Expenses Accrued expenses consist of the following (in thousands): AS OF SEPTEMBER 30, DECEMBER 31, Accrued research and development expenses $ 2,218 $ 2,861 Accrued payroll and other employee benefits 4,806 4,047 Other accrued expenses 1,320 1,109 Total accrued expenses $ 8,344 $ 8,017

Simple Agreement for Future Equ

Simple Agreement for Future Equity	9 Months Ended
	Sep. 30, 2024
Simple Agreement for Future Equity [Abstract]
Simple Agreement for Future Equity	7. Simple Agreement for Future Equity During 2023, the Company entered into SAFEs with various existing investors and related parties with aggregate gross proceeds of $ 24.4 million. The SAFEs granted investors with rights to participate in a future equity financing. The SAFEs have no maturity dates and bear no interest. Upon an equity financing, the SAFEs will automatically convert into the type of stock issued in the financing at a per share conversion price equal to the greater of (i) the purchase amount of the SAFEs divided by the post-money valuation cap price of $ 48.25 per share, or (ii) the purchase amount of the SAFEs divided by the 85 % per share price paid by investors in the financing. Upon an initial public offering, the SAFEs will automatically convert into shares of common stock equal to the purchase amount of the SAFE divided by the discount price (the lower of (a) the price per share of common stock sold to the public by the underwriters in the initial public offering multiplied by the discount rate of 85 % or (b) the post-money valuation cap price of $ 48.25 per share). Other conversion events include liquidity events (a change of control or direct listing). Upon a liquidity event, each investor will automatically be entitled to receive a portion of proceeds equal to the greater of (i) the purchase amounts of the SAFEs, or (ii) the amount payable in the number of common shares equal to the purchase amount of the SAFEs divided by the 85 % per share price. Upon a dissolution event and to the extent sufficient funds are available, the holders of SAFEs shall be entitled to receive cash payments equal to the purchase amount, prior to and in preference to any distribution of any assets or surplus funds to the holders of convertible preferred and common stock. In connection with the closing of the IPO, the Company’s outstanding convertible SAFE shares automatically converted into 2,391,418 shares of common stock.

Collaboration and License Agree

Collaboration and License Agreements	9 Months Ended
	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaboration and License Agreements	8. Collaboration and License Agreements The Company has entered into several agreements with GC Cell and related entities concerning its NK cell therapy platform and manufacturing of its core products, as described below. Option and License Agreement with GC Cell In September 2019, the Company entered into an option and license agreement with GC Cell Corporation (“GC Cell”), formerly Green Cross Cell Corporation, as amended in June 2020 and February 2022 (the “Core Agreement”). Under the Core Agreement, GC Cell granted the Company an exclusive, royalty-bearing license, with the right to sublicense through multiple tiers, under certain intellectual property and technology owned or controlled by GC Cell relating to non-genetically modified and genetically modified NK cells, and culturing, engineering, manufacturing thereof, to research, develop, manufacture, and commercialize NK cell pharmaceutical products in the Artiva Territory, which is anywhere in the world except for Asia, Australia, and New Zealand. GC Cell retained rights under the license to allow it and its affiliates to perform obligations under the Core Agreement and other agreements between the Company and them. Under the Core Agreement, GC Cell agreed to conduct a discovery, research, preclinical development, and manufacturing program under a plan approved by a Joint Steering Committee (the “JSC”), to generate and identify product candidates for nomination as option candidates. GC Cell will bear all costs for its work under the R&D Plan, except that the Company will bear all costs for completing IND-enabling activities performed by GC Cell on behalf of the Company, other than certain efficacy studies. For each product candidate determined by the JSC to be an option candidate, the Company has an exclusive option under the Core Agreement to obtain an exclusive, sublicensable license to research, develop, manufacture and commercialize such candidate in the Artiva Territory for any therapeutic, prophylactic or diagnostic uses in humans, on economic terms to be determined in good faith by the parties. GC Cell retains exclusive rights to the licensed technology in Asia, Australia, and New Zealand, though the Company has the right to request, and GC Cell has agreed to consider in good faith, inclusion of Australia, New Zealand, and/or specific countries in Asia in the Artiva Territory on a product-by-product basis. If the Company elects not to exercise the option with respect to a particular option candidate, GC Cell retains the right to continue development of such candidate. As of September 30, 2024 , the Company has exercised its rights to license four option candidates, AB-101 (AlloNK), AB-201, AB-202, and AB-205, as described below. The Company has control over and will bear the costs of the development, regulatory, manufacturing, and commercialization activities relating to the option candidates for which it has exercised its option, each a licensed product. Accordingly, the Company has certain diligence obligations and must use commercially reasonable efforts to develop and seek regulatory approval for each licensed product in at least one indication in the United States and the European Union, and following regulatory approval in a country, to commercialize such licensed product in at least one indication in such country. The Core Agreement provides that the Company has the right to engage GC Cell or its appropriate affiliate to provide research and manufacturing services for the licensed products being developed by the Company in the Artiva Territory under separately executed service agreements. Under the Core Agreement, the Company is obligated to pay a low single-digit percentage royalty on net sales of any licensed products, the manufacture, use or sale of which is claimed by or uses any Core IP. The royalty rate is subject to reduction under certain scenarios, and royalties are payable on a product-by-product and country-by-country basis, beginning with the first commercial sale of a licensed product and continuing until the later of: (i) expiration of the last-to-expire claim of the licensed patents and jointly owned patents in the country of sale; (ii) expiration of any regulatory exclusivity for a licensed product in that country; and (iii) the tenth anniversary of the first commercial sale of a licensed product in that country. The Company also has the exclusive option to extend its license to the Core IP to be worldwide with respect to products originated from the Company in exchange for a specified increase in the applicable royalty. GC Cell is also obligated to pay the Company a royalty at a rate equal to 50 % of the royalty payable by the Company for such product in the Artiva Territory on net sales outside the Artiva Territory of any licensed product, the manufacture, use or sale of which is claimed by or uses any jointly owned intellectual property. As of September 30, 2024, the Company has not recognized any net sales royalties under the Core Agreement. AB-101 Selected Product License Agreement In November 2019, the Company entered into a license agreement with GC Cell for its AB-101 product candidate, as amended in February 2022 (the “AB-101 Agreement”). AB-101 is the first product for which the Company exercised its option under the Core Agreement. Under the AB-101 Agreement, GC Cell granted the Company an exclusive, royalty-bearing license in the Artiva Territory, with the right to sublicense through multiple tiers, under certain intellectual property and technology owned or controlled by GC Cell, to research, develop, manufacture, and commercialize AB-101. Under the AB-101 Agreement, the Company is obligated to pay tiered royalties in the low-mid to high single-digit percentage range on annual net sales of any licensed AB-101 products. The royalty rate is subject to reduction under certain scenarios, and royalties are payable on a product-by-product and country-by-country basis, beginning with the first commercial sale of a licensed AB-101 product and continuing until the later of: (i) expiration of the last-to-expire claim of the licensed patents and jointly owned patents in the country of sale; (ii) expiration of any regulatory exclusivity for a licensed product in that country; and (iii) the tenth anniversary of the first commercial sale of a licensed product in that country. The Company is also obligated to make milestone payments to GC Cell of: (1) up to $ 22.0 million upon the first achievement of certain development milestones; and (2) up to $ 55.0 million upon the first achievement of certain sales milestones. GC Cell is also obligated to pay the Company a royalty at a rate equal to 50 % of the royalty payable by the Company for such product in the Artiva Territory on net sales outside the Artiva Territory of any licensed AB-101 product, the manufacture, use or sale of which is claimed by or uses any jointly owned intellectual property. As of September 30, 2024 , the Company has no t recognized any net sales royalties or milestones under the AB-101 Agreement. AB-201 Selected Product License Agreement In October 2020, the Company entered into a license agreement with GC Cell for its AB-201 product candidate, as amended in February 2022 (the “AB-201 Agreement”). AB-201 is the second product for which the Company exercised its option under the Core Agreement. Under the AB-201 Agreement, GC Cell granted the Company an exclusive, royalty-bearing license in the Artiva Territory, with the right to sublicense through multiple tiers, under certain intellectual property and technology owned or controlled by GC Cell, to research, develop, manufacture, and commercialize AB-201. Under the AB-201 Agreement, the Company is obligated to pay tiered royalties in the mid to high single-digit percentage range on annual net sales of any licensed AB-201 products. The royalty rate is subject to reduction under certain scenarios, and royalties are payable on a product-by-product and country-by-country basis, beginning with the first commercial sale of a licensed AB-201 product and continuing until the later of: (i) expiration of the last-to-expire claim of the licensed patents and jointly owned patents in the country of sale; (ii) expiration of any regulatory exclusivity for a licensed product in that country; and (iii) the tenth anniversary of the first commercial sale of a licensed product in that country. The Company is also obligated to make milestone payments to GC Cell of: (1) up to $ 25.0 million upon the first achievement of certain development milestones; and (2) up to $ 55.0 million upon the first achievement of certain sales milestones. GC Cell is also obligated to pay the Company a royalty at a rate equal to 50 % of the royalty payable by the Company for such product in the Artiva Territory on net sales outside the Artiva Territory of any licensed AB-201 product, the manufacture, use or sale of which is claimed by or uses any jointly owned intellectual property. In September 2023, the Company entered an amendment to the AB-201 Agreement (the “Amended AB-201 Agreement”). This amendment granted back GC Cell an exclusive, royalty and milestone bearing license to all information and patents controlled by the Company that relate specifically to the research, development, manufacture and use of AB-201, to be used outside of the Artiva Territory. Under the Amended AB-201 Agreement, the Company will receive tiered royalties in the low single-digit percentage range on annual GC Cell net sales of AB-201 outside of the Artiva Territory. The royalties are payable on a product-by-product and country-by-country basis, beginning with the first commercial sale of AB-201 outside of the Artiva Territory and continuing until the later of: (i) expiration of the last-to-expire claim of the licensed patents in the country of sale; (ii) expiration of any regulatory exclusivity for a licensed product in that country; and (iii) the tenth anniversary of the first commercial sale of a licensed product in that country. The Company will also receive milestone payments upon achievement of certain development milestones, totaling $ 1.8 million. In December 2023, GC Cell achieved the first regulatory milestone under the Amended AB-201 Agreement for first IND acceptance for AB-201 outside the Artiva Territory. The Company recognized zero and $ 0.3 million of license and development support-related revenue during the three and nine months ended September 30, 2024, respectively, in the condensed statements of operations and comprehensive income (loss), related to development support activities under the Amended AB-201 Agreement. During the three and nine months ended September 30, 2023, no license and development support-related revenue was recognized. As of September 30, 2024 and December 31, 2023 , total accounts receivable related to the Amended AB-201 Agreement were $ 0.6 million. AB-205 Selected Product License Agreement In December 2022, the Company entered into a license agreement with GC Cell for its AB-205 product candidate (the “AB-205 Agreement”). AB-205 is the fourth product for which the Company exercised its option under the Core Agreement. Under the AB-205 Agreement, GC Cell granted the Company an exclusive, royalty-bearing license in the Artiva Territory, with the right to sublicense through multiple tiers, under certain intellectual property and technology owned or controlled by GC Cell, to research, develop, manufacture, and commercialize AB-205. Under the AB-205 Agreement, the Company is also obligated to pay tiered royalties in the mid to high single-digit percentage range on annual net sales of any licensed AB-205 products. The royalty rate is subject to reduction under certain scenarios, and royalties are payable on a product-by-product and country-by-country basis, beginning with the first commercial sale of a licensed AB-205 product and continuing until the later of: (i) expiration of the last-to-expire claim of the licensed patents and jointly owned patents in the country of sale; (ii) expiration of any regulatory exclusivity for a licensed product in that country; and (iii) the tenth anniversary of the first commercial sale of a licensed product in that country. Upon election by the Company to proceed with clinical development of AB-205 (prior to which the Company may not make, use or sell AB-205 for clinical development purposes), the Company is obligated to pay a one-time payment of $ 2.5 million to GC Cell. Thereafter, the Company is also obligated to make milestone payments to GC Cell of: (i) up to $ 29.5 million upon the first achievement of certain development milestones, excluding any payments for the Development Cost Share as defined in the AB-205 Agreement; and (ii) up to $ 28.0 million upon the first achievement of certain sales milestones. As of September 30, 2024 , the Company has no t recognized any net sales royalties or milestones under the AB-205 Agreement. In connection with the AB-205 License Agreement, the Company recognized zero and $ 0.1 million of expense reimbursements for development costs invoiced to GC Cell for the three and nine months ended September 30, 2024 , respectively, and $ 0.5 million and $ 1.0 million for the three and nine months ended September 30, 2023, respectively. During the three and nine months ended September 30, 2024 , the Company received payments from GC Cell totaling $ 0.7 million and $ 1.7 million, respectively. As of September 30, 2024 and December 31, 2023 , the Company recorded zero and $ 0.6 million, respectively, in the condensed balance sheets as other receivable from GC Cell. Research Services Agreement with GC Cell As contemplated by the Core Agreement, in August 2020 the Company entered into the GC Cell Research Services Agreement, as amended in February 2022, under which GC Cell agreed to provide research services in support of the research and development of one or more of the products the Company has licensed from GC Cell. The agreement provides that the parties will agree to specific projects as work orders under the GC Cell Research Services Agreement. Each work order shall set forth, upon terms mutually agreeable to GC Cell and the Company, the specific services to be performed by GC Cell, the timeline and schedule for the performance of the services, and the compensation to be paid by the Company to GC Cell for the provision of such services, as well as any other relevant terms and conditions (see Note 10). Master Manufacturing Agreement with GC Cell In March 2020, the Company entered into a Master Agreement for Manufacturing Services (the “Manufacturing Agreement”) with GC Cell, under which GC Cell agreed to manufacture specified products under individual work orders for use in the Company’s Phase 1 and Phase 2 clinical trials. Each work order will contain an estimated budget of service fees and out-of-pocket costs to be incurred in the performance of services under the agreement and the work order, as well as additional terms and conditions relating to the estimated budget. The Company will own all results and data generated by GC Cell under the Manufacturing Agreement (see Note 10). Merck Exclusive License and Collaboration Agreement In January 2021, the Company entered into the Exclusive License and Research Collaboration Agreement (the “Merck Collaboration Agreement”) with Merck for the discovery, development, manufacture and commercialization of CAR-NK cells that target certain solid tumor antigens. Merck paid the Company $ 30.0 million upfront for two target programs under the Merck Collaboration Agreement. As part of the Merck Collaboration Agreement, the Company was also eligible to receive additional payments for achieving certain development, regulatory approval and sales milestones, as well as royalties on net sales. In addition, the Company would be reimbursed for the conduct of each research program, including external research costs and manufacture and supply of clinical material for Phase 1 clinical trials. Concurrent with entering into the Merck Collaboration Agreement, the Company also entered into an agreement with GC Cell to obtain exclusive, worldwide rights to GC Cell’s CAR-NK technology with respect to the licensed products and to engage GC Cell to perform services in support of the research programs (“Partnered Program License Agreement”). The Company agreed to reimburse GC Cell for research and development services as these services were provided. The Company was required to pay GC Cell 100 % of regulatory milestones, sales milestones and royalty payments received by Merck relating to products in Asia, Australia and New Zealand and 50 % of upfront payments, license fees, regulatory milestones, sales milestones and royalty payments received by Merck relating to products in all other territories. In October 2023, the Merck Collaboration Agreement and development thereunder was terminated by Merck. The Company applied ASC 808 to the Merck Collaboration Agreement and determined that the agreements were applicable to such guidance. The Company concluded that Merck represented a customer and applied relevant guidance from ASC 606 to account for the Merck Collaboration Agreement. In accordance with this guidance, the Company identified its performance obligations, including its grant of a license to Merck to certain of its intellectual property subject to certain conditions, transfer of technology, its conduct of research services, and its participation in a joint research committee. The Company determined that its grant of a license to Merck to certain of its intellectual property subject to certain conditions was not distinct from other performance obligations because such grant is dependent on the conduct and results of the research services. Additionally, the Company determined that its conduct of research services was not distinct from other performance obligations since the research could not be conducted without also delivering the rights to the license, developed intellectual property and technology transfer. Accordingly, the Company determined that all performance obligations should be accounted for as one combined performance obligation for each target program, and that the combined performance obligation is transferred over the expected term of the conduct of the research services, which is collectively estimated to be four years, which represents the combined terms for the research programs (“Expected Research Term”). The Company assessed the upfront, non-refundable and non-creditable payment of $ 30.0 million received in January 2021 and concluded that there was not a significant financing component to the Merck Collaboration Agreement. The Company also assessed the effects of the variable consideration under the Merck Collaboration Agreement. Such assessment evaluated, among other things, the likelihood of receiving: (i) various clinical, regulatory and commercial milestone payments; and (ii) royalties on net sales. Based on its assessment, the Company concluded that given the substantial uncertainty related to their achievement, such variable consideration was not included in the transaction price. In accordance with ASC 606, the Company determined that the initial transaction price under the Merck Collaboration Agreement equaled $ 58.0 million, consisting of the upfront, non-refundable and non-creditable payment of $ 30.0 million and the aggregate estimated research and development fees of $ 28.0 million. The initial transaction price was allocated evenly to each of the two product targets. The upfront payment of $ 30.0 million was recorded as deferred revenue, and was recognized as revenue over the Expected Research Term as the research services were the primary component of the combined performance obligations. Revenue associated with the upfront payment was recognized based on actual costs incurred as a percentage of the estimated total costs expected to be incurred over the Expected Research. The Company assessed the payments made to GC Cell in connection with the Partnered Program License Agreement and concluded that all payments received from Merck and paid to GC Cell should be reflected within the Company’s condensed financial statements on a gross basis. The Company recognized payments from Merck as collaboration revenue as the performance obligation was satisfied over time, and payments made to GC Cell were recognized as research and development expense, as incurred. The Company recognized zero revenue under the Merck Collaboration Agreement during the three and nine months ended September 30, 2024, and recognized $ 26.7 million and $ 31.1 million of revenue under the Merck Collaboration Agreement during the three and nine months ended September 30, 2023, respectively. Over the course of the Merck Collaboration Agreement through September 30, 2024 , the Company received $ 39.9 million in payments from Merck, of which $ 30.0 million related to the upfront fee, and $ 9.9 million related to reimbursable research services. Affimed Collaboration Agreement On November 1, 2022, the Company entered into a strategic collaboration agreement with Affimed GmbH, a subsidiary of Affimed N.V. (“Affimed”) for the clinical development and commercialization of a combination therapy, for any uses in humans or animals, comprising Affimed’s product consisting of an innate cell engager referred to as “AFM13” and the Company’s product containing an NK cell referred to as AB-101 (the “Affimed Collaboration Agreement”). While the collaboration is initially limited to the United States, the parties will, upon Affimed’s request, in good faith discuss an expansion to certain other territories. The Company has granted Affimed, with respect to the development of the combination therapy an exclusive, and with respect to the promotion of the combination therapy under the Affimed Collaboration Agreement a non-exclusive, non-transferable (except to affiliates and successors in interest), royalty-free and non-sublicensable (with certain exceptions) license under relevant Company patents and know-how. Affimed has granted the Company a non-exclusive, non-transferable (except to affiliates and successors in interest), royalty-free license and non-sublicensable (with certain exceptions) license under relevant Affimed patents and know-how for use in the clinical development of the combination therapy under the Affimed Collaboration Agreement. The financial terms of the Affimed Collaboration Agreement provides that Affimed shall be responsible for all costs associated with the development of the combination therapy (including all clinical trial costs), except that Affimed and the Company shall each bear 50 % of the costs and expenses incurred in connection with the performance of any confirmatory combination therapy clinical trial required by the FDA. The Company shall be solely responsible for all costs incurred by the Company for the supply of AB-101 and IL-2 product used in the clinical trials for the combination therapy, and for carrying out activities assigned to it under the agreed development plan. In addition, under the Affimed Collaboration Agreement, the parties agree to make payments to each other to achieve a proportion of 67 %/ 33 % (Affimed/Company) of revenues generated by both parties from commercial sales of each party’s product as part of the combination therapy. The Company incurred zero and $ 0.1 million of expense in connection with the Affimed Collaboration Agreement during the three and nine months ended September 30, 2024 , respectively, and zero and $ 0.7 million of expense in connection with the Affimed Collaboration Agreement during the three and nine months ended September 30, 2023 , respectively.

Convertible Preferred Stock and

Convertible Preferred Stock and Stockholders' Equity (Deficit)	9 Months Ended
	Sep. 30, 2024
Temporary Equity And Permanent Equity [Abstract]
Convertible Preferred Stock and Stockholders' Equity (Deficit)	9. Convertible Preferred Stock and Stockholders’ Equity (Deficit) Stockholders’ Equity (Deficit) Under the Amended and Restated Certificate of Incorporation dated July 22, 2024, the Company had a total of 710,000,000 shares of capital stock authorized for issuance, consisting of 700,000,000 shares of common stock, par value of $ 0.0001 per share, and 10,000,000 shares of preferred stock, par value of $ 0.0001 per share. Additionally, the Company has authorized 84,556 shares reserved under the terms specified as part of the Company’s Pledge 1 % Movement commitment, in support of its corporate social responsibility and philanthropic pursuits. Convertible Preferred Stock In 2020 and 2021, the Company issued 2,077,165 shares and 1,595,983 shares, respectively, of Series A convertible preferred stock at a price of $ 21.93 per share, resulting in aggregate gross proceeds of $ 70.0 million and total issuance costs of $ 0.4 million. The Company converted a promissory note with a fair value of $ 10.6 million as part of the first closing and reclassified a convertible preferred stock purchase right liability with a fair value of $ 23.7 million into equity as part of the second closing. In 2021, the Company issued 2,487,237 shares of Series B convertible preferred stock at a price of $ 48.25 per share resulting in aggregate gross proceeds of $ 120.0 million and incurred $ 0.4 million of total issuance costs. As of December 31, 2023, the Company’s Series A and Series B convertible preferred stock has been classified as temporary equity in the accompanying condensed balance sheets given that the holders of the convertible preferred stock could cause certain events to occur that are outside of the Company’s control whereby the Company could be obligated to redeem the convertible preferred stock. The carrying value of the convertible preferred stock was not adjusted to the redemption value until the contingent redemption events are considered to be probable of occurring. Immediately upon completion of the IPO, 6,160,385 outstanding shares of convertible preferred stock converted into 6,160,385 shares of common stock. There are no Series A or Series B convertible preferred shares outstanding as September 30, 2024. Common Stock The voting, dividend, and liquidation rights of the holders of the common stock are subject to, and qualified by, the rights, preferences and privileges of the holders of the Series A and Series B convertible preferred stock. The holders of the common stock are entitled to one vote for each share of common stock held at all meetings of stockholders. Common stock reserved for future issuance consisted of the following: AS OF SEPTEMBER 30, DECEMBER 31, Convertible preferred stock — 6,160,385 Common stock options granted and outstanding 2,238,816 1,315,726 Restricted stock units granted and outstanding 533,484 22,514 Shares available for issuance under the 2024 and 2020 1,798,605 323,131 Shares available for issuance under the ESPP Plan 212,000 — Shares available for issuance under the Pledge 1% commitment 84,556 84,556 Total common stock reserved for future issuance 4,867,461 7,906,312 Stock Options In June 2020, the Company adopted the 2020 Equity Incentive Plan (the “Plan”). The Plan provides for the grant of incentive stock options (“ISO”), non-statutory stock options (“NSO”), stock appreciation rights, restricted stock awards, restricted stock unit awards, and other stock awards. The Plan was amended in December 2020, January 2021, July 2021, August 2022, and in April 2024. In April 2024, the Plan was amended to increase the total number of shares reserved under the Plan to 2,083,797 . In July 2024, in connection with the closing of the IPO, the Company’s board of directors adopted the 2024 Equity Incentive Plan (the “2024 Plan”), a successor to and continuation of the 2020 Plan. Upon the effectiveness of the 2024 Plan, 4,572,025 shares of common stock were authorized for issuance which consists of (1) 2,630,000 new shares of common stock, (2) 115,436 shares available for issuance under the 2020 Plan, and (3) up to 1,826,589 shares of common stock subject to outstanding stock awards granted under the 2020 Plan that, on or after the 2024 Plan becomes effective, expire or otherwise terminate prior to exercise or settlement; are not issued because the stock award is settled in cash; are forfeited or repurchased because of the failure to vest; or are reacquired or withheld to satisfy a tax withholding obligation or the purchase or exercise price, if any, as such shares become available from time to time. Furthermore, upon effectiveness of the 2024 Plan, no further grants will be made under the 2020 Plan, and the 2020 Plan will automatically terminate on June 23, 2030. Options granted under the 2024 Plan are exercisable at various dates as determined upon grant and will expire no more than 10 years from their date of grant. The exercise price of each option shall be determined by the board of directors based on the estimated fair value of the Company’s stock on the date of the option grant. The exercise price shall not be less than 100 % of the fair market value of the Company’s common stock at the time the option is granted. Most option grants generally vest 25 % on the first anniversary of the original vesting commencement date, with the balance vesting monthly over the remaining three years and early exercise is permitted. The vesting period generally occurs over four years unless there is a specific performance vesting trigger at which time those shares will vest when the performance trigger is probable to occur. On April 6, 2023, the Company’s board of directors approved a stock option repricing (the “Option Repricing”) in which the exercise price of certain outstanding options to purchase shares of the Company’s common stock under the 2020 Plan was reduced to $ 5.01 per share, the estimated fair value of the Company’s common stock as of December 31, 2022. The Option Repricing was intended to motivate holders of options with exercise prices in excess of the estimated fair value of the Company’s common stock to remain with the Company and work toward its success. The Option Repricing included options granted pursuant to the 2020 Plan that were held by, among others, members of the Company’s board of directors and the Company’s named executive officers. As a result of the Option Repricing, 1,168,651 shares of vested and unvested stock options outstanding as of April 6, 2023, with original exercise prices ranging from $ 5.14 to $ 51.72 per share, were repriced to an exercise price of $ 5.01 per share. The Option Repricing impacted 70 grantees and the total incremental fair value recognized as a result of the repricing was $ 1.5 million. A summary of the Company’s stock option activity under the 2020 and 2024 Plan for the nine months ended September 30, 2024 is as follows: TOTAL WEIGHTED- WEIGHTED- AGGREGATE (in years) (in thousands) Outstanding at December 31, 2023 1,315,726 $ 5.02 9.1 $ 214 Granted 996,389 11.21 — — Exercised ( 5,583 ) 5.00 — — Cancelled ( 67,716 ) 6.56 — — Outstanding at September 30, 2024 2,238,816 $ 7.72 8.9 $ 17,307 Exercisable as of September 30, 2024 1,064,579 $ 5.02 8.4 $ 11,101 The weighted-average grant date fair value of options granted for the nine months ended September 30, 2024 and 2023 , was $ 8.85 and $ 3.29 per share, respectively. The total intrinsic value of options exercised during the nine months ended September 30, 2024 and 2023, was de minimus. Upon the exercise of stock options, the Company will issue new shares of its common stock. Employee Stock Purchase Plan In connection with the closing of the IPO, the Company’s board of directors adopted the 2024 Employee Stock Purchase Plan (the “ESPP”). The ESPP provides for two-year offering periods consisting of four 6-month purchase periods , and at the end of each purchase period employees are able to purchase shares at 85 % of the lower of the fair market value of the Company’s common stock on the first trading day of the offering period or on the last trading day of the purchase period. A new offering is initiated each January 16 and July 16. In the event the fair market value of the Company’s common stock on the first day of any new offering is less than or equal to the fair market value of a ongoing offering, the ongoing offering shall terminate immediately following the purchase of shares of common stock on the purchase date immediately preceding the new offering and participants in the terminated ongoing offering will be automatically enrolled in the new offering. An aggregate of 212,000 shares were initially reserved and available for issuance under the ESPP. The ESPP provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1, beginning on January 1, 2025, by the lesser of 1.0 % of the outstanding number of shares of common stock on the immediately preceding December 31, and 424,000 shares of common stock. No awards were granted under the ESPP as of September 30, 2024. Restricted Stock Unit Awards Restricted stock unit awards (“RSUs”) granted under the 2020 and 2024 Plan are subject to time-based vesting and convert to shares of common stock in accordance with the vesting schedule. RSUs are valued at the estimated fair value of the Company’s stock on the date of grant and are amortized over the requisite service period. The total number of RSUs granted represents the maximum number of RSUs eligible to vest based upon the service conditions set forth in the grant agreements. Employees forfeit unvested RSUs upon termination of employment with a corresponding reversal of expense. During the nine months ended September 30, 2024 and 2023 , 513,620 and zero RSUs were granted by the Company, respectively. As of September 30, 2024 , 533,484 total RSUs were outstanding. Stock-Based Compensation Expense The following table summarizes stock-based compensation expense by condensed financial statement line item in the Company’s statement of operations and comprehensive income (loss) (in thousands): THREE MONTHS ENDED SEPTEMBER 30, NINE MONTHS ENDED SEPTEMBER 30, 2024 2023 2024 2023 Research and development $ 888 $ 791 $ 2,452 $ 2,880 General and administrative 1,019 580 2,344 2,781 Total $ 1,907 $ 1,371 $ 4,796 $ 5,661 In 2023, the Company entered into separation agreements with certain executives, terminating their employment and entering into consulting agreements. Under the separation agreements, service-based requirements for one of the executives were deemed satisfied for all RSUs as of the date of separation. In order for RSUs to vest, there must be a liquidity event and the RSUs must meet the time and service-based requirement prior to the defined Liquidity Event Deadline. There were no outstanding RSUs associated with these executives as of September 30, 2024. The Company recognized zero in incremental compensation cost for the three and nine months ended September 30, 2024 , and $ 0.5 million in incremental compensation cost for the three and nine months ended September 30, 2023 . The separation agreements also provided for extended vesting terms of certain options grants through the term of the consulting agreements. The Company recognized zero in incremental compensation cost for the three and nine months ended September 30, 2024 , and zero and $ 0.2 million in incremental compensation cost for the three and nine months ended September 30, 2023, respectively. The assumptions used in the Black-Scholes option pricing model to determine the fair value of the employee and nonemployee stock option grants issued for the nine months ended September 30, 2024 and 2023, were as follows: NINE MONTHS ENDED SEPTEMBER 30, 2024 2023 Stock price $ 5.18 - $ 15.45 $ 5.00 Risk-free rate of interest 3.5 % - 4.6 % 3.6 % - 4.4 % Expected term (years) 5.1 - 6.1 5.5 - 6.1 Expected stock price volatility 87.4 % - 110.5 % 86.5 % - 88.6 % Expected dividend yield — — As of September 30, 2024 , the unrecognized compensation cost related to outstanding employee and non-employee options was $ 12.2 million and is expected to be recognized as expense over a weighted-average period of 2.9 years. As of September 30, 2024 , the unrecognized compensation cost related to outstanding RSUs was $ 5.7 million and is expected to be recognized as expense over a weighted-average period of 3.9 years.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2024
Related Party Transactions [Abstract]
Related Party Transactions	10. Related Party Transactions Relationship with GC Cell and GC Corp GC Cell and GC Corp, subsidiaries of Green Cross Corp, are stockholders of the Company and are represented on the Company’s board of directors. In November 2019, October 2020, March 2021, and December 2022, the Company entered into a license agreement (collectively, the “License Agreements”) with GC Cell (see Note 8). In August 2020, the Company entered into a Research and Service Agreement with GC Cell in which GC Cell is to provide mutually agreed research services in support of the research and development of one or more of the Selected Products that the Company has licensed from GC Cell under the License Agreements. The Company did no t incur any research and development expense in connection with the agreements for the three and nine months ended September 30, 2024 and 2023. As of September 30, 2024 and December 31, 2023 , the Company had no accounts payable and accrued expenses in connection with the GC Cell License Agreements and Research Service Agreement. In September 2023, the Company and GC Cell amended the AB-201 Agreement (see Note 8). The Company recognized zero and $ 0.3 million of license and development support-related revenue for the three and nine months ended September 30, 2024, respectively, on its condensed statements of operations and comprehensive income (loss), related to GC Cell’s achievement of a defined development milestone and development support activities under the Amended AB-201 Agreement. As of September 30, 2024 and December 31, 2023 , total accounts receivable related to the Amended AB-201 Agreement were $ 0.6 million and $ 0.6 million, respectively. Under the AB-205 Agreement, GC Cell agreed to reimburse the Company for Direct Costs incurred on behalf of GC Cell in accordance with the Development Plan under the AB-205 Agreement, provided that such reimbursed costs are deemed to form part of the Direct Costs incurred and paid by GC Cell (see Note 8). Total reimbursements for development costs invoiced to GC Cell in connection with the AB-205 Agreement were zero and $ 0.1 million for the three and nine months ended September 30, 2024 , respectively, and $ 0.5 million and $ 1.0 million for the three and nine months ended September 30, 2023, respectively. During the three and nine months ended September 30, 2024 , the Company received payments from GC Cell in the amounts of $ 0.7 million and $ 1.7 million, respectively. As of September 30, 2024 and December 31, 2023 , the Company had zero and $ 0.6 million recorded in the condensed balance sheets as other receivable, respectively. In March 2020, the Company entered into the Manufacturing Agreement with GC Cell, where GC Cell is to perform manufacturing services with respect to any biological or chemical product manufactured or to be manufactured for use in Phase 1 or Phase 2 clinical trials. The Company amended the Manufacturing Agreement in June 2020 to include the Company’s right to terminate the agreement at will. The Company incurred $ 1.2 million and $ 2.7 million of research and development expenses in connection with the agreement for the three and nine months ended September 30, 2024 , respectively, and $ 1.4 million and $ 3.2 million of research and development expenses in connection with the agreement for the three and nine months ended September 30, 2023, respectively. As of September 30, 2024 and December 31, 2023 , the Company had $ 1.6 million and $ 2.4 million, respectively, of accounts payable and accrued expenses in connection with the Manufacturing Agreement recorded in the condensed balance sheets. In January 2021, concurrent with entering into the Merck Collaboration Agreement, the Company also entered into a Partnered Program License Agreement with GC Cell to obtain exclusive, worldwide rights to GC Cell’s CAR-NK technology with respect to the licensed products and to engage GC Cell to perform services in support of the research programs. The Company agreed to reimburse GC Cell for research and development services as these services were provided. The Company was required to pay GC Cell 100 % of regulatory milestones, sales milestones and royalty payments received by Merck relating to products in Asia, Australia and New Zealand and 50 % of upfront payments, license fees, regulatory milestones, sales milestones and royalty payments received by Merck relating to products in all other territories. In October 2023, the Merck Collaboration Agreement and development thereunder was terminated by Merck. Relationship with RA Capital RA Capital Healthcare Fund, L.P., RA Capital Nexus Fund, L.P. and Blackwell Partners LLC—Series A (the “RA Capital Funds”) are stockholders of the Company and a member of the Company’s board of directors is affiliated with the RA Capital Funds. In June 2024, the Company entered into a services agreement (the “Blackbird Services Agreement”) with Blackbird Clinical, Inc. (“Blackbird”), an entity controlled by RA Capital Management, L.P. RA Capital Management, L.P. is the investment manager for the RA Capital Funds. Under the terms of the Blackbird Services Agreement, Blackbird provides consulting services in connection with the Company's clinical trials, including study strategy, clinical operations and patient operations. The Company incurred $ 0.1 million of research and development expenses in connection with the consulting services from Blackbird for the three and nine months ended September 30, 2024 . No expenses were incurred with Blackbird for the three and nine months ended September 30, 2023. As of September 30, 2024, and December 31, 2023 , the Company had $ 57 thousand and zero of accounts payable and accrued expenses, respectively, in connection with the Blackbird Services Agreement recorded in the condensed balance sheets.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	11. Commitments and Contingencies Operating Leases The following table presents operating rent expense and related short-term lease costs (in thousands): THREE MONTHS ENDED SEPTEMBER 30, NINE MONTHS ENDED SEPTEMBER 30, 2024 2023 2024 2023 Rent expense $ 1,003 $ 1,056 $ 3,043 $ 3,091 Amount of rent expense related to short-term leases 68 71 203 214 Future minimum annual obligations under the Company’s operating leases with terms in excess of one year are as follows (in thousands): PERIOD ENDED SEPTEMBER 30, 2024 (remaining) 1,017 2025 4,007 2026 3,418 2027 3,520 Thereafter 5,916 Total minimum lease payments 17,878 Less: amount representing interest ( 3,104 ) Present value of operating lease liabilities 14,774 Less: operating lease liabilities, current ( 3,614 ) Operating lease liabilities, net of current portion $ 11,160 As the Company’s leases do not provide an implicit rate, the Company uses an incremental borrowing rate based on average discount rate were as follows: AS OF SEPTEMBER 30, DECEMBER 31, Weighted-average remaining lease term 4.6 years 5.3 years Weighted-average discount rate 7.7 % 7.8 % On July 22, 2022, the Company entered into a sublease (the “Sublease Agreement”) with Origis Operating Services, LLC, (the “Sublessee”), whereby the Company agreed to sublease to Sublessee all of the 13,405 rentable square feet of office space in San Diego, California currently leased by the Company under the Executive Drive Lease. The sublease commenced on August 1, 2022 , and has a term through December 31, 2025 . The aggregate base rent is approximately $ 2.6 million commencing August 1, 2022. The Company records sublease income as a reduction of general and administrative expense. The expected undiscounted cash flows to be received from the sublease are as follows (in thousands): PERIOD ENDED SEPTEMBER 30, 2024 (remaining) $ 215 2025 873 Total $ 1,088 The Company recognized $ 0.2 million and $ 0.6 million of sublease income for the three and nine months ended September 30, 2024 , respectively and $ 0.2 million and $ 0.6 million of sublease income for the three and nine months ended September 30, 2023 , respectively.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2024
Subsequent Events [Abstract]
Subsequent Events	12. Subsequent Events For the purposes of the condensed financial statements as of September 30, 2024, and the three and nine months then ended, the Company has evaluated the subsequent events through November 12, 2024, the date the condensed financial statements were issued.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of condensed financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed financial statements and the reported amounts of expenses during the reporting period. Accounting estimates and management judgments reflected in the condensed financial statements include: revenue recognized, the accrual of research and development expenses, common stock, stock-based compensation, SAFEs and operating lease liabilities. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may materially differ from these estimates and assumptions.
Investments	Investments The Company holds investments in commercial paper, government and government agency bonds, and corporate bonds. The Company has classified its investment securities as current and non-current assets on the condensed balance sheets based on each security's contractual maturity date, and all investment securities are accounted for as available-for-sale because these investment securities are considered available for use in operations. The Company carries these securities at fair value and reports unrealized gains and losses as a separate component of accumulated other comprehensive income. The cost of debt securities is adjusted for amortization of purchase premiums and accretion of discounts to maturity. Such amortization and accretion are included in other income in the condensed statements of operations and comprehensive income (loss). Realized gains and losses on sales of securities are determined using the specific identification method and recorded in other income in the condensed statements of operations and comprehensive income (loss). As of September 30, 2024, and December 31, 2023 , accrued interest receivables on investments were $ 0.7 million and $ 0.1 million, respectively, and are included in prepaid expenses and other current assets in the condensed balance sheets. The Company does not measure an allowance for credit losses for accrued interest receivables. For the purposes of identifying and measuring an impairment, accrued interest is excluded from both the fair value and amortized cost basis of the investment. Uncollectible accrued interest receivables associated with an impaired debt security are reversed against interest income upon identification of the impairment. No accrued interest receivables were written off during the three and nine months ended September 30, 2024 and 2023 .
Restricted Cash	Restricted Cash Restricted cash is comprised of cash that is restricted as to withdrawal or use under the terms of certain contractual agreements. Restricted cash as of September 30, 2024 and December 31, 2023 , was $ 0.3 million consisting of collateral for letters of credit related to the Company’s lease agreements and is included in non-current assets in the condensed balance sheets (see Note 11).
Net Income (Loss) Per Share	Net Income (Loss) Per Share Basic net income (loss) per share is calculated by dividing the net income (loss) by the weighted-average number of common shares outstanding for the period. Diluted net income (loss) per share is computed by dividing the net income (loss) by the weighted-average number of shares of common stock and common stock equivalents outstanding for the period. Common stock equivalents are only included when their effect is dilutive. The Company’s potentially dilutive securities include shares of its convertible preferred stock, as well as outstanding stock options and restricted stock units under the Company’s equity incentive plan and have been excluded from the computation of diluted net loss per share, for all periods except the three months ended September 30, 2023, as they would be anti-dilutive to the net loss per share. The Company recorded net income for the three months ended September 30, 2023. The Company used the treasury stock method and if-converted method to determine the weighted-average number of shares of common stock equivalents outstanding for the three months ended September 30, 2023. The following table sets forth the computation of basic and diluted net income (loss) per share (in thousands, except share and per share data): THREE MONTHS ENDED NINE MONTHS ENDED SEPTEMBER 30, SEPTEMBER 30, SEPTEMBER 30, SEPTEMBER 30, Basic Net Income (Loss) per share Net income (loss) $ ( 17,472 ) $ 11,279 $ ( 49,278 ) $ ( 16,722 ) Weighted average common shares outstanding - basic 18,896,829 806,714 6,883,271 800,541 Net income (loss) per share - basic $ ( 0.92 ) $ 13.98 $ ( 7.16 ) $ ( 20.89 ) Diluted Net Income (Loss) per share Net income (loss) $ ( 17,472 ) $ 11,279 $ ( 49,278 ) $ ( 16,722 ) Weighted average common shares outstanding - basic 18,896,829 806,714 6,883,271 800,541 Weighted average effect of dilutive securities: Series A preferred stock — 3,673,148 — — Series B preferred stock — 2,487,237 — — Weighted average common shares outstanding - diluted 18,896,829 6,967,099 6,883,271 800,541 Net income (loss) per share - diluted $ ( 0.92 ) $ 1.62 $ ( 7.16 ) $ ( 20.89 ) The following table sets forth the outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because their inclusion would be anti-dilutive for the nine months ended September 30, 2024 and 2023: AS OF AS OF Convertible preferred stock — 6,160,385 Unvested restricted stock units 533,484 22,514 Options to purchase common stock 2,238,816 1,323,348 Total 2,772,300 7,506,247
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”). ASU 2020-06 was issued to reduce the complexity associated with accounting for certain financial instruments with characteristics of liabilities and equity. ASU 2020-06 reduces the number of accounting models for convertible debt instruments and redeemable convertible preferred stock and improves the disclosures for convertible instruments and related earnings per share guidance. ASU 2020-06 also amends the guidance for the derivatives scope exception for contracts in an entity’s own equity and improves and amends the related earnings per share guidance. For public entities that qualify as a filer with the Securities and Exchange Commission, excluding entities eligible to be smaller reporting companies, ASU 2020-06 is effective for fiscal annual periods beginning after December 15, 2021, including interim periods within those fiscal years. For nonpublic entities, ASU 2020-06 is effective for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early adoption is permitted, but no earlier than fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. ASU 2020-06 must be adopted as of the beginning of a Company’s annual fiscal year. The Company adopted this standard on January 1, 2024 , and the adoption of the standard did not have a material impact on its financial statements. In November 2023, the FASB issued ASU 2023-07, Segment Reporting—Improvements to Reportable Segment Disclosures (“ASU 2023-07”). The update requires entities to disclose their significant segment expense categories and amounts for each reportable segment. Significance is assessed using both quantitative and qualitative factors depending on the facts and circumstances. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023, and interim periods in fiscal years beginning after December 15, 2024. The Company is currently evaluating the impact that this standard will have on the related disclosures in its financial statements. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures (“ASU 2023-09”). The update requires enhanced disclosures on income taxes paid, adds disaggregation of continuing operations before income taxes between foreign and domestic earnings and defines specific categories for the reconciliation of jurisdictional tax rate to effective tax rate. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024, and can be applied on a prospective basis. The Company is currently evaluating the impact that this standard will have on the related disclosures in its financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Summary of Basic and Diluted Net Income (Loss) Per Share	The following table sets forth the computation of basic and diluted net income (loss) per share (in thousands, except share and per share data): THREE MONTHS ENDED NINE MONTHS ENDED SEPTEMBER 30, SEPTEMBER 30, SEPTEMBER 30, SEPTEMBER 30, Basic Net Income (Loss) per share Net income (loss) $ ( 17,472 ) $ 11,279 $ ( 49,278 ) $ ( 16,722 ) Weighted average common shares outstanding - basic 18,896,829 806,714 6,883,271 800,541 Net income (loss) per share - basic $ ( 0.92 ) $ 13.98 $ ( 7.16 ) $ ( 20.89 ) Diluted Net Income (Loss) per share Net income (loss) $ ( 17,472 ) $ 11,279 $ ( 49,278 ) $ ( 16,722 ) Weighted average common shares outstanding - basic 18,896,829 806,714 6,883,271 800,541 Weighted average effect of dilutive securities: Series A preferred stock — 3,673,148 — — Series B preferred stock — 2,487,237 — — Weighted average common shares outstanding - diluted 18,896,829 6,967,099 6,883,271 800,541 Net income (loss) per share - diluted $ ( 0.92 ) $ 1.62 $ ( 7.16 ) $ ( 20.89 )
Summary of anti-dilutive securities excluded from calculation of earnings per share	The following table sets forth the outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because their inclusion would be anti-dilutive for the nine months ended September 30, 2024 and 2023: AS OF AS OF Convertible preferred stock — 6,160,385 Unvested restricted stock units 533,484 22,514 Options to purchase common stock 2,238,816 1,323,348 Total 2,772,300 7,506,247

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Summary of assets and liabilities measured at fair value on recurring basis	The following table presents information about the Company’s financial assets and liabilities that are measured at fair value on a recurring basis and indicates their respective levels within the fair value hierarchy (in thousands): AS OF SEPTEMBER 30, 2024 CLASSIFICATION TOTAL LEVEL 1 LEVEL 2 LEVEL 3 Assets Money market funds Cash and cash equivalents $ 35,353 $ 35,353 $ — $ — Commercial paper Cash and cash equivalents 11,495 — 11,495 — Government bonds Cash and cash equivalents 6,281 — 6,281 — Commercial paper Short-term investments 73,180 — 73,180 — Government agency bonds Short-term investments 4,505 — 4,505 — Corporate bonds Short-term investments 13,065 — 13,065 — Government and government Long-term investments 45,142 — 45,142 — Corporate bonds Long-term investments 7,824 — 7,824 — Total assets $ 196,845 $ 35,353 $ 161,492 $ — AS OF DECEMBER 31, 2023 CLASSIFICATION TOTAL LEVEL 1 LEVEL 2 LEVEL 3 Assets Money market funds Cash and cash equivalents $ 28,517 $ 28,517 $ — $ — Commercial paper Short-term investments 2,090 — 2,090 — Government and government Short-term investments 19,982 — 19,982 — Corporate bonds Short-term investments 1,395 — 1,395 — Total assets $ 51,984 $ 28,517 $ 23,467 $ — Liabilities SAFEs Liabilities $ 25,100 $ — $ — $ 25,100 Total liabilities $ 25,100 $ — $ — $ 25,100
Summary of significant inputs not observable in the fair value measurements	The following tables summarize the significant inputs not observable in the market upon which the fair value measurements associated with the SAFEs were determined: VALUATION TECHNIQUE UNOBSERVABLE INPUT AS OF DECEMBER 31, 2023 Liabilities SAFEs Scenario-based approach Probability weighting 15.0 % - 70.0 % Discount rate 20.1 % Remaining term to event (in years) 0.50 - 0.75
Summary of changes in fair value associated with level 3 financial instruments	The following table summarizes the changes in fair value associated with Level 3 financial instruments held during the periods presented (in thousands): SAFEs Balance at December 31, 2023 $ 25,100 Changes in fair value of SAFEs 3,597 Conversion of SAFEs to common stock ( 28,697 ) Balance at September 30, 2024 $ —

Cash, Cash Equivalents and In_2

Cash, Cash Equivalents and Investments (Tables)	9 Months Ended
	Sep. 30, 2024
Cash and Cash Equivalents [Abstract]
Summary of company's cash and cash equivalents, short-term investments and long-term investments	The following table summarizes the Company’s cash and cash equivalents, short-term investments, and long-term investments for each of the periods presented (in thousands): AS OF SEPTEMBER 30, 2024 CLASSIFICATION MATURITY AMORTIZED GROSS GROSS FAIR Cash and money market funds Cash and cash equivalents Less than three months $ 38,105 $ — $ — $ 38,105 Commercial paper Cash and cash equivalents Less than three months 11,493 2 — 11,495 Government bonds Cash and cash equivalents Less than three months 6,258 23 — 6,281 Commercial paper Short-term investments 1 year or less 73,098 82 — 73,180 Government agency bonds Short-term investments 1 year or less 4,497 8 — 4,505 Corporate bonds Short-term investments 1 year or less 13,042 23 — 13,065 Government and government agency Long-term investments Greater than 1 year 44,955 187 — 45,142 Corporate bonds Long-term investments Greater than 1 year 7,811 13 — 7,824 Total cash and cash equivalents, short- $ 199,259 $ 338 $ — $ 199,597 AS OF DECEMBER 31, 2023 CLASSIFICATION MATURITY AMORTIZED GROSS GROSS FAIR Cash and money market funds Cash and cash equivalents Less than three months $ 53,504 $ — $ — $ 53,504 Commercial paper Short-term investments 1 year or less 2,048 42 — 2,090 Government and government agency Short-term investments 1 year or less 19,728 254 — 19,982 Corporate bonds Short-term investments 1 year or less 1,383 12 — 1,395 Total cash, cash equivalents and short- $ 76,663 $ 308 $ — $ 76,971

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	9 Months Ended
	Sep. 30, 2024
Property, Plant and Equipment [Abstract]
Schedule of property and equipment of net consisted	Property and equipment, net consisted of the following (in thousands): AS OF SEPTEMBER 30, DECEMBER 31, Lab equipment $ 10,284 $ 9,760 Furniture and fixtures 872 871 Computers and software 616 607 Leasehold improvements 410 390 12,182 11,628 Less accumulated depreciation ( 5,325 ) ( 3,532 ) Total property and equipment, net $ 6,857 $ 8,096

Accrued Expenses (Tables)

Accrued Expenses (Tables)	9 Months Ended
	Sep. 30, 2024
Accrued Liabilities, Current [Abstract]
Summary of accrued expenses	Accrued expenses consist of the following (in thousands): AS OF SEPTEMBER 30, DECEMBER 31, Accrued research and development expenses $ 2,218 $ 2,861 Accrued payroll and other employee benefits 4,806 4,047 Other accrued expenses 1,320 1,109 Total accrued expenses $ 8,344 $ 8,017

Convertible Preferred Stock a_2

Convertible Preferred Stock and Stockholders' Equity (Deficit) (Tables)	9 Months Ended
	Sep. 30, 2024
Temporary Equity And Permanent Equity [Abstract]
Summary of common stock reserved for future issuance	Common stock reserved for future issuance consisted of the following: AS OF SEPTEMBER 30, DECEMBER 31, Convertible preferred stock — 6,160,385 Common stock options granted and outstanding 2,238,816 1,315,726 Restricted stock units granted and outstanding 533,484 22,514 Shares available for issuance under the 2024 and 2020 1,798,605 323,131 Shares available for issuance under the ESPP Plan 212,000 — Shares available for issuance under the Pledge 1% commitment 84,556 84,556 Total common stock reserved for future issuance 4,867,461 7,906,312
Summary of company's stock option activity under the plan	A summary of the Company’s stock option activity under the 2020 and 2024 Plan for the nine months ended September 30, 2024 is as follows: TOTAL WEIGHTED- WEIGHTED- AGGREGATE (in years) (in thousands) Outstanding at December 31, 2023 1,315,726 $ 5.02 9.1 $ 214 Granted 996,389 11.21 — — Exercised ( 5,583 ) 5.00 — — Cancelled ( 67,716 ) 6.56 — — Outstanding at September 30, 2024 2,238,816 $ 7.72 8.9 $ 17,307 Exercisable as of September 30, 2024 1,064,579 $ 5.02 8.4 $ 11,101
Summary of stock-based compensation expense	The following table summarizes stock-based compensation expense by condensed financial statement line item in the Company’s statement of operations and comprehensive income (loss) (in thousands): THREE MONTHS ENDED SEPTEMBER 30, NINE MONTHS ENDED SEPTEMBER 30, 2024 2023 2024 2023 Research and development $ 888 $ 791 $ 2,452 $ 2,880 General and administrative 1,019 580 2,344 2,781 Total $ 1,907 $ 1,371 $ 4,796 $ 5,661
Summary of black-scholes option pricing model	The assumptions used in the Black-Scholes option pricing model to determine the fair value of the employee and nonemployee stock option grants issued for the nine months ended September 30, 2024 and 2023, were as follows: NINE MONTHS ENDED SEPTEMBER 30, 2024 2023 Stock price $ 5.18 - $ 15.45 $ 5.00 Risk-free rate of interest 3.5 % - 4.6 % 3.6 % - 4.4 % Expected term (years) 5.1 - 6.1 5.5 - 6.1 Expected stock price volatility 87.4 % - 110.5 % 86.5 % - 88.6 % Expected dividend yield — —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Summary of operating rent expenses	The following table presents operating rent expense and related short-term lease costs (in thousands): THREE MONTHS ENDED SEPTEMBER 30, NINE MONTHS ENDED SEPTEMBER 30, 2024 2023 2024 2023 Rent expense $ 1,003 $ 1,056 $ 3,043 $ 3,091 Amount of rent expense related to short-term leases 68 71 203 214
Summary of future minimum annual obligations under the company's operating leases	Future minimum annual obligations under the Company’s operating leases with terms in excess of one year are as follows (in thousands): PERIOD ENDED SEPTEMBER 30, 2024 (remaining) 1,017 2025 4,007 2026 3,418 2027 3,520 Thereafter 5,916 Total minimum lease payments 17,878 Less: amount representing interest ( 3,104 ) Present value of operating lease liabilities 14,774 Less: operating lease liabilities, current ( 3,614 ) Operating lease liabilities, net of current portion $ 11,160
Summary of incremental borrowing rate	As the Company’s leases do not provide an implicit rate, the Company uses an incremental borrowing rate based on average discount rate were as follows: AS OF SEPTEMBER 30, DECEMBER 31, Weighted-average remaining lease term 4.6 years 5.3 years Weighted-average discount rate 7.7 % 7.8 %
Summary of expected undiscounted cashflow	The expected undiscounted cash flows to be received from the sublease are as follows (in thousands): PERIOD ENDED SEPTEMBER 30, 2024 (remaining) $ 215 2025 873 Total $ 1,088

Organization, Liquidity and B_2

Organization, Liquidity and Basis of Presentation - Additional Information (Detail) $ / shares in Units, $ in Thousands				3 Months Ended	9 Months Ended
	Jul. 25, 2024 USD ($) shares	Jul. 22, 2024 USD ($) $ / shares shares	Jul. 12, 2024	Sep. 30, 2024 USD ($) shares	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Date of incorporation					Feb. 14, 2019
Retained earnings accumulated deficit				$ (230,589)	$ (230,589)		$ (181,311)
Cash flow from used in operating activities					(40,382)	$ (36,755)
Cash, cash equivalents and investments				199,600	199,600
Cumulative gross proceeds from convertible notes derivative instruments and redeemable convertible preferred stock				$ 401,400	401,400
Payment of stock issuance costs					4,163
Proceeds from issuance of common stock					166,507
Redeemable convertible preferred stock [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stockholders equity stock split			0.2057
IPO [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Sale of stock issue price per share | $ / shares		$ 12
Proceeds from initial public offer	$ 162,300	$ 167,000
Stock issued during the period shares new issues | shares		13,920,000
Payment of stock issuance costs		$ 15,900
Sale of stock net consideration received on the transaction		$ 151,100
Over-allotment option [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Proceeds from initial public offer	$ 12,000
Stock issued during the period shares new issues | shares	1,000,000
Proceeds from issuance of common stock	$ 11,200
Commissions	$ 800
Common Stock [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stockholders equity stock split			0.2057
Stock issued during the period shares new issues | shares				14,920,000
Merck exclusive license and collaboration agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Receipt from the counterparty				$ 39,900	$ 39,900

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Accounting Policies [Line Items]
Accrued interest receivables on short-term investments	$ 700	$ 100
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Current, Statement of Financial Position [Extensible Enumeration]	Prepaid Expense and Other Assets, Current	Prepaid Expense and Other Assets, Current
Restricted cash	$ 258	$ 258	$ 258
Change in accounting principle, ASU, adopted [true false]	true
Change in accounting principle, ASU, adoption date	Jan. 01, 2024
Change in accounting principle, ASU, immaterial effect [true false]	true
Accounting Standards Update [Extensible Enumeration]	us-gaap:AccountingStandardsUpdate202006Member
Letter of credit [Member]
Accounting Policies [Line Items]
Restricted cash	$ 300	$ 300

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Basic and Diluted Net Income (Loss) Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Basic Net Income (Loss) per share
Net income (loss)	$ (17,472)	$ (17,843)	$ (13,963)	$ 11,279	$ (11,284)	$ (16,717)	$ (49,278)	$ (16,722)
Weighted average common shares outstanding - basic	18,896,829			806,714			6,883,271	800,541
Net income (loss) per share - basic	$ (0.92)			$ 13.98			$ (7.16)	$ (20.89)
Diluted Net Income (Loss) per share
Weighted average common shares outstanding - diluted	18,896,829			6,967,099			6,883,271	800,541
Net income (loss) per share - diluted	$ (0.92)			$ 1.62			$ (7.16)	$ (20.89)
Series A preferred stock [Member]
Diluted Net Income (Loss) per share
Weighted average effect of dilutive securities				3,673,148
Series B preferred stock [Member]
Diluted Net Income (Loss) per share
Weighted average effect of dilutive securities				2,487,237

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Summary of Anti-dilutive Securities Excluded from Calculation of Earnings Per Share (Detail) - shares	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of earnings per share	2,772,300	7,506,247
Convertible preferred stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of earnings per share	0	6,160,385
Unvested restricted stock units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of earnings per share	533,484	22,514
Employee Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of earnings per share	2,238,816	1,323,348

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Assets
Total assets	$ 196,845	$ 51,984
Liabilities
Liabilities		25,100
Total liabilities		25,100
Money market funds [Member]
Assets
Cash and cash equivalents	35,353	28,517
Commercial paper [Member]
Assets
Cash and cash equivalents	11,495
Short-term investments	73,180	2,090
Government Agency Bonds [Member]
Assets
Short-term investments	4,505
Government Bonds [Member]
Assets
Cash and cash equivalents	6,281
Government and government agency bonds [Member]
Assets
Short-term investments		19,982
Long-term investments	45,142
Corporate bonds [Member]
Assets
Short-term investments	13,065	1,395
Long-term investments	7,824
Level 1 [Member]
Assets
Total assets	35,353	28,517
Level 1 [Member] | Money market funds [Member]
Assets
Cash and cash equivalents	35,353	28,517
Level 2 [Member]
Assets
Total assets	161,492	23,467
Level 2 [Member] | Commercial paper [Member]
Assets
Cash and cash equivalents	11,495
Short-term investments	73,180	2,090
Level 2 [Member] | Government Agency Bonds [Member]
Assets
Short-term investments	4,505
Level 2 [Member] | Government Bonds [Member]
Assets
Cash and cash equivalents	6,281
Level 2 [Member] | Government and government agency bonds [Member]
Assets
Short-term investments		19,982
Long-term investments	45,142
Level 2 [Member] | Corporate bonds [Member]
Assets
Short-term investments	13,065	1,395
Long-term investments	$ 7,824
Level 3 [Member]
Liabilities
Liabilities		25,100
Total liabilities		$ 25,100

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail)		3 Months Ended
	Jul. 22, 2024 shares	Sep. 30, 2024 $ / shares shares	May 29, 2024 $ / shares	May 28, 2024 $ / shares
Common stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Issuance of common shares upon the conversion of SAFE notes | shares	2,391,418	2,391,418
Simple agreement for future equity [Member] | Equity financing [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative cap price		48.25		48.25
Discount rate on issuance of common stock		85%		85%
Simple agreement for future equity [Member] | Liquidity event [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative cap price		48.25		48.25
Discount rate on issuance of common stock		85%		85%
Simple agreement for future equity [Member] | Excluding liquidity event [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative cap price			48.25
Discount rate on issuance of common stock		85%	85%

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Significant Inputs Not Observable in the Fair Value Measurements (Detail) - SAFE [Member] - Scenario-based approach [Member]	Dec. 31, 2023 yr
Discount rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability measurement input	0.201
Minimum [Member] | Probability weighting [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability measurement input	0.15
Minimum [Member] | Remaining term to event (in years) [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability measurement input	0.5
Maximum [Member] | Probability weighting [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability measurement input	0.70
Maximum [Member] | Remaining term to event (in years) [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability measurement input	0.75

Fair Value Measurements - Sum_3

Fair Value Measurements - Summary of Changes in Fair Value Associated With Level 3 Financial Instruments (Detail) - Simple agreement for future equity [Member] $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 25,100
Changes in fair value of SAFEs	3,597
Conversion of SAFEs to common stock	(28,697)
Ending Balance	$ 0

Cash, Cash Equivalents and In_3

Cash, Cash Equivalents and Investments - Summary of Company's Cash and Cash Equivalents, Short-term Investments and Long-term Investments (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	$ 55,881	$ 53,504	$ 65,885
Total cash and cash equivalents, short-term investments, and long-term investments, Amortized Cost	199,259	76,663
Gross Unrealized Gains	338	308
Total cash and cash equivalents, short-term investments, and long-term investments, Fair Market Value	199,597	76,971
Cash and money market funds [Member]
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	38,105	53,504
Cash and cash equivalents, Fair Market Value	$ 38,105	$ 53,504
Cash and money market funds [Member] | Cash and cash equivalents [Member] | Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period	3 months	3 months
Commercial paper [Member]
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	$ 11,493
Short-term investments, Amortized Cost		$ 2,048
Cash and cash equivalents, Fair Market Value	11,495
Short-term investments, Fair Market Value	73,180	2,090
Commercial paper [Member] | Cash and cash equivalents [Member]
Debt Securities, Available-for-Sale [Line Items]
Gross Unrealized Gains	$ 2
Commercial paper [Member] | Cash and cash equivalents [Member] | Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period	3 months
Commercial paper [Member] | Short-term investments [Member]
Debt Securities, Available-for-Sale [Line Items]
Short-term investments, Amortized Cost	$ 73,098
Gross Unrealized Gains	$ 82	$ 42
Commercial paper [Member] | Short-term investments [Member] | Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period	1 year	1 year
Government bonds [Member]
Debt Securities, Available-for-Sale [Line Items]
Cash and cash equivalents	$ 6,258
Cash and cash equivalents, Fair Market Value	6,281
Government bonds [Member] | Cash and cash equivalents [Member]
Debt Securities, Available-for-Sale [Line Items]
Gross Unrealized Gains	$ 23
Government bonds [Member] | Cash and cash equivalents [Member] | Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period	3 months
Government agency bonds [Member]
Debt Securities, Available-for-Sale [Line Items]
Short-term investments, Amortized Cost	$ 4,497
Short-term investments, Fair Market Value	4,505
Government agency bonds [Member] | Short-term investments [Member]
Debt Securities, Available-for-Sale [Line Items]
Gross Unrealized Gains	$ 8
Government agency bonds [Member] | Short-term investments [Member] | Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period	1 year
Corporate bonds [Member]
Debt Securities, Available-for-Sale [Line Items]
Short-term investments, Amortized Cost	$ 13,042	$ 1,383
Long-term investments, Amortized Cost	7,811
Short-term investments, Fair Market Value	13,065	1,395
Long-term investments, Fair Market Value	7,824
Corporate bonds [Member] | Short-term investments [Member]
Debt Securities, Available-for-Sale [Line Items]
Gross Unrealized Gains	$ 23	$ 12
Corporate bonds [Member] | Short-term investments [Member] | Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period	1 year	1 year
Corporate bonds [Member] | Long-term investments [Member]
Debt Securities, Available-for-Sale [Line Items]
Gross Unrealized Gains	$ 13
Corporate bonds [Member] | Long-term investments [Member] | Minimum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period	1 year
Government and government agency bonds [Member]
Debt Securities, Available-for-Sale [Line Items]
Short-term investments, Amortized Cost		$ 19,728
Long-term investments, Amortized Cost	$ 44,955
Short-term investments, Fair Market Value		19,982
Long-term investments, Fair Market Value	45,142
Government and government agency bonds [Member] | Short-term investments [Member]
Debt Securities, Available-for-Sale [Line Items]
Gross Unrealized Gains		$ 254
Government and government agency bonds [Member] | Short-term investments [Member] | Maximum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period		1 year
Government and government agency bonds [Member] | Long-term investments [Member]
Debt Securities, Available-for-Sale [Line Items]
Gross Unrealized Gains	$ 187
Government and government agency bonds [Member] | Long-term investments [Member] | Minimum [Member]
Debt Securities, Available-for-Sale [Line Items]
Investment maturity period	1 year

Cash, Cash Equivalents and In_4

Cash, Cash Equivalents and Investments - Additional Information (Detail)	Sep. 30, 2024 USD ($)
Cash and Cash Equivalents [Abstract]
Gross unrealized losses	$ 0
Allowance for credit losses	$ 0

Property and Equipment, Net - S

Property and Equipment, Net - Summary of Property and Equipment of Net Consisted (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Property and equipment	$ 12,182	$ 11,628
Less accumulated depreciation	(5,325)	(3,532)
Total property and equipment, net	6,857	8,096
Lab equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	10,284	9,760
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	872	871
Computers and software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	616	607
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	$ 410	$ 390

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Property, Plant and Equipment [Abstract]
Depreciation	$ 0.6	$ 0.6	$ 1.8	$ 1.7

Accrued Expenses - Summary of A

Accrued Expenses - Summary of Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Accrued Liabilities, Current [Abstract]
Accrued research and development expenses	$ 2,218	$ 2,861
Accrued payroll and other employee benefits	4,806	4,047
Other accrued expenses	1,320	1,109
Total accrued expenses	$ 8,344	$ 8,017

Simple Agreement for Future E_2

Simple Agreement for Future Equity - Additional Information (Detail) $ in Millions		3 Months Ended	9 Months Ended
	Jul. 22, 2024 shares	Sep. 30, 2024 $ / shares shares	Sep. 30, 2024 USD ($) $ / shares	May 29, 2024 $ / shares	May 28, 2024 $ / shares
Common stock [Member]
Option Indexed to Issuer's Equity [Line Items]
Issuance of common shares upon the conversion of SAFE notes | shares	2,391,418	2,391,418
Simple agreement for future equity [Member]
Option Indexed to Issuer's Equity [Line Items]
Proceeds from Related Party Debt | $			$ 24.4
Simple agreement for future equity [Member] | Equity financing [Member]
Option Indexed to Issuer's Equity [Line Items]
Derivative cap price		48.25	48.25		48.25
Discount rate on issuance of common stock		85%	85%		85%
Simple agreement for future equity [Member] | Liquidity event [Member]
Option Indexed to Issuer's Equity [Line Items]
Derivative cap price		48.25	48.25		48.25
Discount rate on issuance of common stock		85%	85%		85%
Simple agreement for future equity [Member] | Excluding liquidity event [Member]
Option Indexed to Issuer's Equity [Line Items]
Derivative cap price				48.25
Discount rate on issuance of common stock		85%	85%	85%

Collaboration and License Agr_2

Collaboration and License Agreements - Additional Information (Detail)				1 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($) Units	Feb. 28, 2022 USD ($)	Dec. 31, 2021 USD ($)	Nov. 30, 2022	Jan. 31, 2021 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue not from contract with customer								$ 251,000
Accounts receivable net current	$ 569,000					$ 569,000		569,000		$ 1,034,000
Other receivable current	$ 132,000					132,000		132,000		724,000
Option And License Agreement With GC Cell [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of products units for which the option has been exercised by the company | Units	4
Royalty percentage to be paid by the counterparty	50%
AB-101 Selected Product License Agreement with GC cell [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty percentage to be paid by the counterparty		50%
AB-101 Selected Product License Agreement with GC cell [Member] | Development milestone [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone amount payable		$ 22,000,000
AB-101 Selected Product License Agreement with GC cell [Member] | Sales milestone [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone amount payable		$ 55,000,000
Milestone Amount Recognized						0
Royaly expenses recognized								0
AB-201 Selected Product License Agreement with GC cell [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty percentage to be paid by the counterparty		50%
Revenue not from contract with customer						0		300,000
Accounts receivable net current	$ 600,000					600,000		600,000		600,000
AB-201 Selected Product License Agreement with GC cell [Member] | Development milestone [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone amount payable		$ 25,000,000
Milestone payment receivable							$ 1,800,000		$ 1,800,000
AB-201 Selected Product License Agreement with GC cell [Member] | Sales milestone [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone amount payable		$ 55,000,000
AB-205 Selected Product License Agreement with GC cell [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royaly expenses recognized						0		0
Accounts receivable net current											$ 2,500,000
Research and development expenses reimbursed						0	500,000	100,000	1,000,000
Other receivable current	$ 0					0		0		$ 600,000
Receipt from the counterparty						700,000		1,700,000
AB-205 Selected Product License Agreement with GC cell [Member] | Development milestone [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone amount payable											29,500,000
AB-205 Selected Product License Agreement with GC cell [Member] | Sales milestone [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payment receivable											$ 28,000,000
Merck exclusive license and collaboration agreement [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payment received			$ 30,000,000		$ 30,000,000
Upfront payment received and non refundable					$ 30,000,000
Performance obligation transaction price			58,000,000
Contract with customer liability			30,000,000
Performance obligation transaction price towards research and development fees			$ 28,000,000
Contract with customer liability revenue recognized						0	26,700,000	0	31,100,000
Receipt from the counterparty						39,900,000		39,900,000
Upfront fee received								30,000,000
Upfront fee received related to reimbursable research services								$ 9,900,000
Partnered program licensing agreement with GC cell [Member] | Products in asia australia and new zealand [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payment percentage					100%
Partnered program licensing agreement with GC cell [Member] | Products in other territories [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payment percentage					50%
Affimed collaboration agreement [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of costs to be incurred in connection with the performance of confimatory combination				50%
Percentage of costs to be borne by the counterparty				50%
Revenue share of the company in percentage								67%
Revenue share of the counterparty in percentage								33%
Expenses incurred in connection with the agreement						$ 0	$ 0	$ 100,000	$ 700,000

Convertible Preferred Stock a_3

Convertible Preferred Stock and Stockholders' Equity (Deficit) - Additional Information (Detail) - USD ($)		3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 05, 2023	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2021	Dec. 31, 2020	Jul. 22, 2024	Jun. 30, 2024	Apr. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Apr. 06, 2023	Mar. 31, 2023	Dec. 31, 2022
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Stock shares authorized temporary and permanent shares									710,000,000
Common stock shares authorized									700,000,000
Common stock par or stated value per share									$ 0.0001
Preferred stock shares authorized									10,000,000
Preferred stock convertible in to common stock		6,160,385		6,160,385
Offering periods				The ESPP provides for two-year offering periods consisting of four 6-month purchase periods
Common stock reserved for future issuance		4,867,461		4,867,461		7,906,312
Temporary equity par or stated value per share									$ 0.0001
Common stock shares reserved for future issuance		4,867,461		4,867,461		7,906,312
Movement commitement percentage									1%
Stock issued during the period conversion of convertible notes value		$ 216,413,000
Warrant liability converted into equity value							$ 23,700,000
Outstanding number of shares of common stock						1%
Shares of common stock		424,000		424,000
Share based compensation by share based award purchase price of common stock as a percentage of market fair value				85%
Share-based payment arrangement, option [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Common stock reserved for future issuance		2,238,816		2,238,816		1,315,726
Common stock shares reserved for future issuance		2,238,816		2,238,816		1,315,726
Restricted stock units (RSUs) [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Common stock reserved for future issuance		533,484		533,484		22,514
Common stock shares reserved for future issuance		533,484		533,484		22,514
Common stock shares outstanding		0		0
Share based compensation non vested award cost not yet recognized period for recognition				3 years 10 months 24 days
2024 amended equity incentive plan [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Common stock reserved for future issuance											2,083,797
Common stock shares reserved for future issuance											2,083,797
2024 amended equity incentive plan [Member] | Share-based payment arrangement, option [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based award expiration period				10 years
Share based compensation by share based award purchase price of common stock as a percentage of market fair value				100%
Share based compensation by share based award vesting rights percentage				25%
Share based compensation by share based award vesting period				4 years
Share based compensation by share based award exercise price of options outstanding														$ 5.01
Share based compensation by shares based award number of options for which exercise price was modified during the period	1,168,651
Share based compensation shares authorized under stock option plans exercise price range lower range limit	$ 5.14
Share based compensation shares authorized under stock option plans exercise price range upper range limit	$ 51.72
Share based compensation by share based payment award modification incremental cost						$ 1,500,000
Share-Based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Exercise Price														$ 5.01
2024 amended equity incentive plan [Member] | Restricted stock units (RSUs) [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation non vested stock options cost not yet recognized		$ 5,700,000		$ 5,700,000
2024 equity incentive plan [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based award number of shares authorized for issuance									4,572,025
2024 equity incentive plan [Member] | New shares of common stock [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based award number of shares authorized for issuance									2,630,000
2024 equity incentive plan [Member] | Shares available for issuance under the two thousand and twenty plan [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based award number of shares authorized for issuance									115,436
2024 equity incentive plan [Member] | Common stock subject to outstanding awards granted [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based award number of shares authorized for issuance									1,826,589
2020 and 2024 Equity Incentive Plan [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based award exercise price of options outstanding		$ 7.72		$ 7.72		$ 5.02
Share based compensation by share based award equity instruments other than options outstanding non vested		2,238,816		2,238,816		1,315,726
Share based compensation non vested stock options cost not yet recognized		$ 12,200,000		$ 12,200,000
2020 and 2024 Equity Incentive Plan [Member] | Share-based payment arrangement, option [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation non vested award cost not yet recognized period for recognition				2 years 10 months 24 days
2020 and 2024 Equity Incentive Plan [Member] | Restricted stock units (RSUs) [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based award equity instruments other than options granted during the period				513,620	0
Share based compensation by share based award equity instruments other than options outstanding non vested		533,484		533,484
Share based compensation non vested award cost not yet recognized period for recognition				3 years 10 months 24 days
Separation agreement with certain executives terminating employment [Member] | Share-based payment arrangement, option [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based payment award modification incremental cost		$ 0	$ 200,000	$ 0	$ 200,000
Separation agreement with certain executives terminating employment [Member] | Restricted stock units (RSUs) [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Share based compensation by share based payment award modification incremental cost		$ 0	$ 500,000	$ 0	$ 500,000
Class a redeemable convertible preferred stock [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Temporary equity shares outstanding			3,673,148		3,673,148	3,673,148				3,673,148		3,673,148	3,673,148		3,673,148	3,673,148
Temporary equity stock issued during the period shares new issues							1,595,983	2,077,165
Temporary equity issue price per share							$ 21.93	$ 21.93
Cumulative gross proceeds form redeemable preferred convertible preferred stock							$ 70,000,000
Redeemable convertible preferred stock issuance costs cumulative							400,000
Convertible notes payable [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Stock issued during the period conversion of convertible notes value							10,600,000
Series B Redeemable Convertible Preferred Stock [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Temporary equity shares authorized		0		0		10,909,091
Temporary equity shares outstanding		0	2,487,237	0	2,487,237	2,487,237				2,487,237		2,487,237	2,487,237		2,487,237	2,487,237
Temporary equity par or stated value per share		$ 0.0001		$ 0.0001		$ 0.0001
Cumulative gross proceeds form redeemable preferred convertible preferred stock							120,000,000
Redeemable convertible preferred stock issuance costs cumulative							$ 400,000
Temporary equity shares issued		0		0		2,487,237	2,487,237
Shares issued, price per share							$ 48.25
Class A and class B redeemable convertible preferred stock [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Temporary equity shares outstanding		0		0
One percent movement commitment [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Common stock reserved for future issuance									84,556
Common stock shares reserved for future issuance									84,556
IPO [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Temporary equity shares outstanding		6,160,385		6,160,385
Employee Stock Purchase Plan [Member]
Disclosure In Entirety Of Temporary And Permanent Equity [Line Items]
Common stock reserved for future issuance		212,000		212,000		0
Common stock shares reserved for future issuance		212,000		212,000		0
Share based awards under ESPP		0		0

Convertible Preferred Stock a_4

Convertible Preferred Stock and Stockholders' Equity (Deficit) - Summary of Common Stock Reserved for Future Issuance (Detail) - shares	Sep. 30, 2024	Dec. 31, 2023
Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	4,867,461	7,906,312
Shares available for issuance under the pledge one percent commitement [Member]
Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	84,556	84,556
2024 and 2020 equity incentive plan [Member]
Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	1,798,605	323,131
Share-based payment arrangement, option [Member]
Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	2,238,816	1,315,726
Restricted stock units (RSUs) [Member]
Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	533,484	22,514
Shares available for issuance under the ESPP Plan [Member]
Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	212,000	0
Redeemable convertible preferred stock [Member]
Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	0	6,160,385

Convertible Preferred Stock a_5

Convertible Preferred Stock and Stockholders' Equity (Deficit) - Summary of Company's Stock Option Activity Under the Plan (Detail) - 2020 and 2024 Equity Incentive Plan [Member] $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Outstanding at December 31, 2023 | shares	1,315,726
Granted | shares	996,389
Exercised | shares	(5,583)
Cancelled | shares	(67,716)
Outstanding at September 30, 2024 | shares	2,238,816	1,315,726
Exercisable as of September 30, 2024 | shares	1,064,579
Outstanding at December 31, 2023 | $ / shares	$ 5.02
Granted | $ / shares	11.21
Exercised | $ / shares	5
Cancelled | $ / shares	6.56
Outstanding at September 30, 2024 | $ / shares	7.72	$ 5.02
Exercisable as of September 30, 2024 | $ / shares	$ 5.02
Weighted - average remaining contractual term	8 years 10 months 24 days	9 years 1 month 6 days
Weighted - average remaining contractual term	8 years 4 months 24 days
Aggregate intrinsic value | $	$ 17,307	$ 214
Aggregate intrinsic value | $	$ 11,101

Convertible Preferred Stock a_6

Convertible Preferred Stock and Stockholders' Equity (Deficit) - Summary of Company's Stock Option Activity Under the Plan (Parenthetical) (Detail) - $ / shares	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
2020 and 2024 Equity Incentive Plan [Member] | Share-based payment arrangement, option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share based compensation by share based award weighted average fair value of options granted during the period	$ 8.85	$ 3.29

Convertible Preferred Stock a_7

Convertible Preferred Stock and Stockholders' Equity (Deficit) - Summary of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 1,907	$ 1,371	$ 4,796	$ 5,661
Research and development [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	888	791	2,452	2,880
General and administrative [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 1,019	$ 580	$ 2,344	$ 2,781

Convertible Preferred Stock a_8

Convertible Preferred Stock and Stockholders' Equity (Deficit) - Summary of Black-Scholes Option Pricing Model (Detail) - 2024 amended equity incentive plan [Member] - Share-based payment arrangement, option [Member] - $ / shares	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock price		$ 5
Maximum [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock price	$ 15.45
Risk-free rate of interest	4.60%	4.40%
Expected term (years)	6 years 1 month 6 days	6 years 1 month 6 days
Expected stock price volatility	110.50%	88.60%
Minimum [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock price	$ 5.18
Risk-free rate of interest	3.50%	3.60%
Expected term (years)	5 years 1 month 6 days	5 years 6 months
Expected stock price volatility	87.40%	86.50%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Jan. 31, 2021
Related Party Transaction [Line Items]
Research and development expenses	$ 13,524	$ 13,065	$ 37,011	$ 39,098
Revenue not from contract with customer			251
Accounts receivable net current	569		569		$ 1,034
Other receivable current	132		132		724
GC cell [Member] | Research and service agreement one [Member]
Related Party Transaction [Line Items]
Research and development expenses	0	0	0	0
Accounts payable and accrued liabilities current	0		0		0
GC cell [Member] | Option and license agreement for AB 201 selected product as amended [Member]
Related Party Transaction [Line Items]
Revenue not from contract with customer	0		300
Accounts receivable net current	600		600		600
GC cell [Member] | AB two hundred and five selected product license agreement [Member]
Related Party Transaction [Line Items]
Research and development expenses reimbursed	0	500	100	1,000
Other receivable current	0		0		600
Receipt from the counterparty	700		1,700
GC cell [Member] | Manufacturing agreement [Member]
Related Party Transaction [Line Items]
Research and development expenses	1,200	1,400	2,700	3,200
Accounts payable and accrued liabilities current	1,600		1,600		2,400
GC cell [Member] | Partnered program licensing agreement [Member] | Products in asia australia and new zealand [Member]
Related Party Transaction [Line Items]
Milestone payment percentage						100%
GC cell [Member] | Partnered program licensing agreement [Member] | Products in other territories [Member]
Related Party Transaction [Line Items]
Milestone payment percentage						50%
RA Capital Management, LP [Member] | Blackbird Services Agreement [Member]
Related Party Transaction [Line Items]
Research and development expenses	100	$ 0	100	$ 0
Accounts payable and accrued liabilities current	$ 57		$ 57		$ 0

Commitments and Contingencies -

Commitments and Contingencies - Summary of Operating Rent Expenses (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Leases [Abstract]
Rent expense	$ 1,003	$ 1,056	$ 3,043	$ 3,091
Amount of rent expense related to short-term leases	$ 68	$ 71	$ 203	$ 214

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Future Minimum Annual Obligations Under the Company's Operating Leases (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Leases [Abstract]
2024 (remaining)	$ 1,017
2025	4,007
2026	3,418
2027	3,520
Thereafter	5,916
Total minimum lease payments	17,878
Less: amount representing interest	(3,104)
Present value of operating lease liabilities	14,774
Less: operating lease liabilities, current	(3,614)	$ (3,596)
Operating lease liabilities, net of current portion	$ 11,160	$ 13,316

Commitments and Contingencies_3

Commitments and Contingencies - Summary of Incremental Borrowing Rate (Detail)	Sep. 30, 2024	Dec. 31, 2023
Leases [Abstract]
Weighted-average remaining lease term	4 years 7 months 6 days	5 years 3 months 18 days
Weighted-average discount rate	7.70%	7.80%

Commitments and Contingencies_4

Commitments and Contingencies - Additional Information (Detail) $ in Millions		3 Months Ended		9 Months Ended
	Jul. 22, 2022 USD ($) ft²	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)
Other Commitments [Line Items]
Sublease income		$ 0.2	$ 0.2	$ 0.6	$ 0.6
Office space [Member]
Other Commitments [Line Items]
Area of sublessee | ft²	13,405
Operating sublease monthly rent	$ 2.6
Office space [Member] | Minimum [Member]
Other Commitments [Line Items]
Operating sublease date of commencement of contract	Aug. 01, 2022
Office space [Member] | Maximum [Member]
Other Commitments [Line Items]
Operating sublease expirary date of contract	Dec. 31, 2025

Commitments and Contingencies_5

Commitments and Contingencies - Summary of Expected Undiscounted Cashflow (Detail) $ in Thousands	Sep. 30, 2024 USD ($)
Leases [Abstract]
2024 (remaining)	$ 215
2025	873
Total	$ 1,088