Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating expense
Research and development	$ 8,683	$ 2,015	$ 27,103	$ 7,152
General and administrative	2,227	2,070	7,192	5,762
Total operating expense	10,910	4,085	34,295	12,914
Loss from operations	(10,910)	(4,085)	(34,295)	(12,914)
Other income (expense)
Interest income	39	4	87	38
Interest expense	(20)	(6)	(1,593)	(13)
Net loss on extinguishment of debt			(2,387)
Gain on forgiveness of debt			149
Change in fair value of warrant liabilities	76	(3)	(750)	238
Total other income (expense)	95	(5)	(4,494)	263
Net loss and comprehensive loss	$ (10,815)	$ (4,090)	$ (38,789)	$ (12,651)
Net loss per share basic and diluted	$ (0.11)	$ (0.09)	$ (0.45)	$ (0.30)
Weighted-average common shares outstanding     basic and diluted	102,325,238	46,989,700	86,579,881	41,781,121