Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Collaboration and license revenue	$ 4,000		$ 389,000
Operating expenses:
Research and development	23,573,000	$ 7,575,000	72,057,000	$ 14,263,000
General and administrative	6,847,000	2,898,000	24,158,000	8,048,000
Change in fair value of contingent consideration and contingent value rights liabilities	167,000		21,563,000
Amortization of intangible assets	423,000	0	1,265,000	0
Total operating expenses	31,010,000	10,473,000	119,043,000	22,311,000
Gain on sale of assets to equity method investment			7,227,000
Loss from operations	(31,006,000)	(10,473,000)	(111,427,000)	(22,311,000)
Other income (expense):
Other income (expense), net	(69,000)	20,000	(175,000)	135,000
Change in fair value of redeemable convertible preferred stock tranche liability		(8,364,000)		(9,533,000)
Loss before income taxes and share of net loss of equity method investment	(31,075,000)	(18,817,000)	(111,602,000)	(31,709,000)
Income tax benefit	463,000	0	1,204,000	0
Share of net loss of equity method investment	(84,000)		(84,000)
Net loss	$ (30,696,000)	$ (18,817,000)	$ (110,482,000)	$ (31,709,000)
Net loss per share attributable to common stockholders, basic and diluted	$ (0.69)	$ (4.50)	$ (2.54)	$ (7.65)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted	44,661	4,185	43,563	4,147
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax of $0	$ 202,000	$ 87,000	$ 339,000	$ (79,000)
Unrealized gain on marketable securities, net of tax of $0	(1,000)		23,000
Total other comprehensive income (loss)	201,000	87,000	362,000	(79,000)
Comprehensive loss	$ (30,495,000)	$ (18,730,000)	$ (110,120,000)	$ (31,788,000)