STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues:
License fees and royalties	$ 1,393	$ 253	$ 460
Operating expenses:
Research and development	85,727	51,488	52,072
General and administrative	29,665	25,678	20,893
Total operating expenses	115,392	77,166	72,965
Loss from operations	(113,999)	(76,913)	(72,505)
Interest income	527	1,828	4,221
Interest expense	(3,740)	(760)
Change in fair value of equity investment		60	(195)
Other income and (expense), net	1,100	168	(69)
Net loss	$ (116,112)	$ (75,617)	$ (68,548)
Basic and diluted net loss per share	$ (0.35)	$ (0.28)	$ (0.36)
Shares used in computing basic and diluted net loss per share	327,631,814	271,460,265	190,160,311