CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenues:
Grant revenue	$ 1,329	$ 1,822
Collaboration revenue	$ 740	$ 247
Type of Revenue [Extensible List]	us-gaap:LicenseMember	us-gaap:LicenseMember
Total revenues	$ 2,069	$ 2,069
Operating expenses:
Research and development	8,979	16,971
General and administrative	7,317	15,305
Restructuring	0
Total operating expenses	16,296	32,276
Loss from operations	(14,227)	(30,207)
Other income (expense):
Interest income	963	72
Other income (expense), net	(2)	(13)
Interest expense related to the sale of future royalties	0	(2,488)
Change in fair value of derivative liability	0	(193)
Total other income (expense), net	961	(2,622)
Net loss	$ (13,266)	$ (32,829)
Net loss per share, basic and diluted	$ (0.25)	$ (1.01)
Net loss per share, basic and diluted	$ (0.25)	$ (1.01)
Weighted average common shares outstanding, basic and diluted	52,527,018	32,606,715
Weighted average common shares outstanding, basic and diluted:	52,527,018	32,606,715
Comprehensive loss:
Net loss	$ (13,266)	$ (32,829)
Other comprehensive gain (loss):
Unrealized gain (loss) on marketable securities	0	(4)
Net unrealized gains (losses) on securities	0	(4)
Total comprehensive loss	$ (13,266)	$ (32,833)