Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Revenues:
Total revenues	$ 240	$ 2,380	$ 4,486	$ 61,831
Operating expenses:
Cost of revenue	(11)	50	0	161
Research and development	151,463	195,178	367,617	400,416
Selling, general and administrative	22,231	25,744	68,458	92,330
Restructuring, long-lived assets impairment and related charges, net	0	12,712	(182)	38,939
Total operating expenses	173,683	233,684	435,893	531,846
Loss from operations	(173,443)	(231,304)	(431,407)	(470,015)
Other income:
Change in fair value of equity investments	1,335	1,130	4,335	(4,356)
Interest income	9,363	17,527	32,436	57,656
Other expense, net	(228)	(893)	(74)	(1,715)
Total other income	10,470	17,764	36,697	51,585
Loss before (provision for) benefit from income taxes	(162,973)	(213,540)	(394,710)	(418,430)
(Provision for) benefit from income taxes	(168)	(177)	(354)	1,059
Net loss	$ (163,141)	$ (213,717)	$ (395,064)	$ (417,371)
Net loss per share, basic (in USD per share)	$ (1.17)	$ (1.56)	$ (2.86)	$ (3.07)
Net loss per share, diluted (in USD per share)	$ (1.17)	$ (1.56)	$ (2.86)	$ (3.07)
Weighted-average shares outstanding, basic (in shares)	138,930,173	136,653,753	138,287,533	136,058,223
Weighted-average shares outstanding, diluted (in shares)	138,930,173	136,653,753	138,287,533	136,058,223
Collaboration revenue
Revenues:
Total revenues	$ (65)	$ (1,102)	$ (630)	$ (2,034)
Contract revenue
Revenues:
Total revenues	0	1,391	3,390	54,468
Grant revenue
Revenues:
Total revenues	$ 305	$ 2,091	$ 1,726	$ 9,397