Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Revenues:
Total revenues	$ 26	$ 48	$ 214	$ 232
Operating expenses:
Research and development (Includes $13, ($2), $19 and ($32) from a related party)	141	123	402	347
General and administrative (Includes $3, $—, $5, and $— from a related party)	27	30	84	92
Impairment of long-lived assets	0	0	0	20
Total operating expenses	168	153	486	459
Loss from operations	(142)	(105)	(272)	(227)
Non-operating income (expense):
Interest and other income, net	10	14	31	40
Interest expense	(3)	(1)	(6)	(2)
Total non-operating income, net	7	13	25	38
Loss before income taxes	(135)	(92)	(247)	(189)
Income tax expense	0	0	0	0
Net loss	$ (135)	$ (92)	$ (247)	$ (189)
Net loss per share:
Basic (in dollars per share)	$ (1.27)	$ (1.00)	$ (2.39)	$ (2.11)
Diluted (in dollars per share)	$ (1.27)	$ (1.00)	$ (2.39)	$ (2.11)
Shares used to compute net loss per share:
Basic (in shares)	106.5	91.4	103.7	89.6
Diluted (in shares)	106.5	91.4	103.7	89.6
License and Development Services Revenue
Revenues:
Total revenues	$ 20	$ 41	$ 192	$ 204
Other Collaboration Revenue
Revenues:
Total revenues	$ 6	$ 7	$ 22	$ 28