Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating expenses:
Research and development (including related party expenses of $2359, $1,331 and $1,137 in 2021, 2020 and 2019, respectively)	$ 78,411	$ 73,564	$ 45,607
General and administrative	25,259	16,017	8,546
Total operating expenses	103,670	89,581	54,153
Loss from operations	(103,670)	(89,581)	(54,153)
Other income (expense), net:
Interest expense	(7)	(7)	(40)
Interest income	344	244	632
Grant income	1,585	2,478	237
Realized gains on marketable securities	2
Foreign currency transaction gains (losses)	1,669	(2,351)	(135)
Change in fair value of the redeemable convertible preferred stock tranche liability			3,185
Total other income (expense), net	3,593	364	3,879
Net loss	$ (100,077)	$ (89,217)	$ (50,274)
Net loss per share, basic and diluted	$ (1.93)	$ (3.02)	$ (13.25)
Weighted-average shares outstanding, basic and diluted	51,922,108	29,545,810	3,795,090