CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Operating expenses
Research and development	$ 9,007	$ 18,853	$ 16,922	$ 21,725
General and administrative	10,558	6,757	20,677	10,942
Total operating expenses	19,565	25,610	37,599	32,667
Loss from operations	(19,565)	(25,610)	(37,599)	(32,667)
Other income (expense), net	94	(342)	109	(362)
Net loss	(19,471)	(25,952)	(37,490)	(33,029)
Other comprehensive income (loss)
Foreign currency translation adjustment	10	0	10	0
Comprehensive loss	$ (19,461)	$ (25,952)	$ (37,480)	$ (33,029)
Shares used in calculating net loss per common share - basic (in shares)	215,862,977	195,572,189	210,806,330	190,960,775
Shares used in calculating net loss per common share - diluted (in shares)	215,862,977	195,572,189	210,806,330	190,960,775
Net loss per share of common stock - basic (in USD per share)	$ (0.09)	$ (0.13)	$ (0.18)	$ (0.17)
Net loss per share of common stock - diluted (in USD per share)	$ (0.09)	$ (0.13)	$ (0.18)	$ (0.17)