Unaudited Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Accumulated other comprehensive income (loss)	Accumulated deficit	Noncontrolling interests
Beginning balance (in shares) at Dec. 31, 2021	8,700,885
Beginning balance at Dec. 31, 2021	$ 107,808
Ending balance (in shares) at Mar. 31, 2022	8,700,885
Ending balance at Mar. 31, 2022	$ 107,808
Beginning balance (in shares) at Dec. 31, 2021		2,059,072
Beginning balance at Dec. 31, 2021	(81,784)	$ 2	$ 816	$ 0	$ (96,997)	$ 14,395
Stockholders' Equity (Deficit)
Exercise of stock options (in shares)		2,572
Stock-based compensation	89		89
Unrealized gain (loss) on marketable securities	(158)			(158)
Net loss	(11,312)				(11,312)
Ending balance (in shares) at Mar. 31, 2022		2,061,644
Ending balance at Mar. 31, 2022	$ (93,165)	$ 2	905	(158)	(108,309)	14,395
Beginning balance (in shares) at Dec. 31, 2021	8,700,885
Beginning balance at Dec. 31, 2021	$ 107,808
Ending balance (in shares) at Sep. 30, 2022	8,700,885
Ending balance at Sep. 30, 2022	$ 107,808
Beginning balance (in shares) at Dec. 31, 2021		2,059,072
Beginning balance at Dec. 31, 2021	(81,784)	$ 2	816	0	(96,997)	14,395
Stockholders' Equity (Deficit)
Net loss	(44,487)
Ending balance (in shares) at Sep. 30, 2022		2,190,008
Ending balance at Sep. 30, 2022	$ (126,108)	$ 2	1,139	(160)	(141,484)	14,395
Beginning balance (in shares) at Mar. 31, 2022	8,700,885
Beginning balance at Mar. 31, 2022	$ 107,808
Ending balance (in shares) at Jun. 30, 2022	8,700,885
Ending balance at Jun. 30, 2022	$ 107,808
Beginning balance (in shares) at Mar. 31, 2022		2,061,644
Beginning balance at Mar. 31, 2022	(93,165)	$ 2	905	(158)	(108,309)	14,395
Stockholders' Equity (Deficit)
Stock-based compensation	58		58
Unrealized gain (loss) on marketable securities	(39)			(39,000)
Net loss	(14,848)				(14,848)
Ending balance (in shares) at Jun. 30, 2022		2,061,644
Ending balance at Jun. 30, 2022	$ (107,994)	$ 2	963	(197)	(123,157)	14,395
Ending balance (in shares) at Sep. 30, 2022	8,700,885
Ending balance at Sep. 30, 2022	$ 107,808
Stockholders' Equity (Deficit)
Exercise of stock options (in shares)		128,364
Exercise of stock options	88		88
Stock-based compensation	88		88
Unrealized gain (loss) on marketable securities	37			37
Net loss	(18,327)				(18,327)
Ending balance (in shares) at Sep. 30, 2022		2,190,008
Ending balance at Sep. 30, 2022	$ (126,108)	$ 2	1,139	(160)	(141,484)	14,395
Beginning balance (in shares) at Dec. 31, 2022	8,700,885
Beginning balance at Dec. 31, 2022	$ 107,808
Convertible preferred stock
Conversion of convertible preferred stock and non-controlling interests to common stock (in shares)	(8,700,885)
Conversion of convertible preferred stock and non-controlling interests to common stock	$ (107,808)
Ending balance (in shares) at Mar. 31, 2023	0
Ending balance at Mar. 31, 2023	$ 0
Beginning balance (in shares) at Dec. 31, 2022		2,217,737
Beginning balance at Dec. 31, 2022	(142,670)	$ 2	1,197	(41)	(158,223)	14,395
Stockholders' Equity (Deficit)
Stock-based compensation	265		265
Unrealized gain (loss) on marketable securities	177			177
Issuance of common stock for cash in pre-closing financing (in shares)		3,730,608
Issuance of common stock for cash in pre-closing financing	30,640	$ 4	30,636
Issuance of common stock upon settlement of convertible promissory note, accrued interest, and related derivative liability (in shares)		5,059,338
Issuance of common stock upon settlement of convertible promissory note, accrued interest, and related derivative liability	42,447	$ 5	42,442
Issuance of common stock to Sesen Bio shareholders in reverse capitalization (in shares)		10,374,272
Issuance of common stock to Sesen Bio shareholders in reverse capitalization	72,044	$ 10	72,034
Conversion of convertible preferred stock and non-controlling interests to common stock (in shares)		18,872,711
Conversion of convertible preferred stock and non-controlling interests to common stock	107,809	$ 19	122,185			(14,395)
Net loss	(24,642)				(24,642)
Ending balance (in shares) at Mar. 31, 2023		40,254,666
Ending balance at Mar. 31, 2023	$ 86,070	$ 40	268,759	136	(182,865)	0
Beginning balance (in shares) at Dec. 31, 2022	8,700,885
Beginning balance at Dec. 31, 2022	$ 107,808
Ending balance (in shares) at Sep. 30, 2023	0
Ending balance at Sep. 30, 2023	$ 0
Beginning balance (in shares) at Dec. 31, 2022		2,217,737
Beginning balance at Dec. 31, 2022	$ (142,670)	$ 2	1,197	(41)	(158,223)	14,395
Stockholders' Equity (Deficit)
Exercise of stock options (in shares)	49,770
Net loss	$ (65,921)
Ending balance (in shares) at Sep. 30, 2023		40,304,436
Ending balance at Sep. 30, 2023	$ 46,298	$ 40	270,029	373	(224,144)	0
Beginning balance (in shares) at Mar. 31, 2023	0
Beginning balance at Mar. 31, 2023	$ 0
Ending balance (in shares) at Jun. 30, 2023	0
Ending balance at Jun. 30, 2023	$ 0
Beginning balance (in shares) at Mar. 31, 2023		40,254,666
Beginning balance at Mar. 31, 2023	86,070	$ 40	268,759	136	(182,865)	0
Stockholders' Equity (Deficit)
Exercise of stock options (in shares)		14,910
Exercise of stock options	52		52
Stock-based compensation	330		330
Unrealized gain (loss) on marketable securities	129			129
Net loss	(19,876)				(19,876)
Ending balance (in shares) at Jun. 30, 2023		40,269,576
Ending balance at Jun. 30, 2023	$ 66,705	$ 40	269,141	265	(202,741)	0
Ending balance (in shares) at Sep. 30, 2023	0
Ending balance at Sep. 30, 2023	$ 0
Stockholders' Equity (Deficit)
Exercise of stock options (in shares)		34,860
Exercise of stock options	40		40
Stock-based compensation	848		848
Unrealized gain (loss) on marketable securities	108			108
Net loss	(21,403)				(21,403)
Ending balance (in shares) at Sep. 30, 2023		40,304,436
Ending balance at Sep. 30, 2023	$ 46,298	$ 40	$ 270,029	$ 373	$ (224,144)	$ 0