Condensed 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
Income Statement [Abstract]
Grant and other revenue		$ 730		$ 1,107
Operating expenses
Research and development	$ 1,800	2,994	$ 6,632	6,971
General and administrative	2,135	226	4,537	707
Total operating expenses	3,935	3,220	11,169	7,678
Loss from operations	(3,935)	(2,490)	(11,169)	(6,571)
Other income (expense)
Change in fair value of preferred stock tranche rights liability and preferred stock warrant liability			(81,157)
Interest income	37		45	1
Interest expense	(23)		(23)
Other income	19		47
Total other income (expense)	33		(81,088)	1
Net loss	(3,902)	(2,490)	(92,257)	(6,570)
Other comprehensive loss
Unrealized loss on marketable securities	(28)		(28)
Comprehensive loss	$ (3,930)	$ (2,490)	$ (92,285)	$ (6,570)
Net loss per common share, basic and diluted	$ (0.10)	$ (5.94)	$ (7.00)	$ (15.68)
Weighted-average shares outstanding, basic and diluted	38,266,593	419,124	13,177,983	419,124