Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating expenses:
Research and development	$ 9,804	$ 11,786
General and administrative	5,373	4,704
Total operating expenses	15,177	16,490
Loss from operations	(15,177)	(16,490)
Other income (expense):
Interest expense	(66)	(1,848)
Interest income	9	1
Loss on conversion of convertible notes	0	(711)
Other expense	3	0
Net loss and comprehensive loss	$ (15,231)	$ (19,048)
Net loss per share, basic and diluted	$ (0.35)	$ (0.59)
Weighted average common shares outstanding, basic and diluted	43,212,803	32,027,161