Condensed Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
Revenue	$ 1,482	$ 1,610	$ 7,720	$ 5,573
Operating expenses:
Research and development	(24,606)	(21,052)	(71,822)	(58,797)
General and administrative	(8,823)	(7,671)	(25,698)	(19,712)
Total operating expenses	(33,429)	(28,723)	(97,520)	(78,509)
Loss from operations	(31,947)	(27,113)	(89,800)	(72,936)
Interest and other income (expense), net	1,332	68	1,539	204
Net loss	(30,615)	(27,045)	(88,261)	(72,732)
Net loss attributable to common stockholders	$ (30,615)	$ (27,045)	$ (88,261)	$ (72,732)
Net loss per share, attributable to common stockholders:
Basic (USD per share)	$ (0.65)	$ (0.75)	$ (2.22)	$ (2.03)
Diluted (USD per share)	$ (0.65)	$ (0.75)	$ (2.22)	$ (2.03)
Shares used in computing net loss per share attributable to common stockholders:
Basic (in shares)	46,799,058	35,906,303	39,735,342	35,787,022
Diluted (in shares)	46,799,058	35,906,303	39,735,342	35,787,022
Comprehensive loss:
Net loss	$ (30,615)	$ (27,045)	$ (88,261)	$ (72,732)
Net unrealized loss on short-term investments	(1,195)	(10)	(2,253)	(8)
Total other comprehensive loss	(1,195)	(10)	(2,253)	(8)
Comprehensive loss	$ (31,810)	$ (27,055)	$ (90,514)	$ (72,740)