Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Operating expenses:
Research and development	$ 2,451	$ 14,038	$ 22,410	$ 45,582
General and administrative	4,344	7,639	22,461	21,192
Goodwill impairment charge	825	0	825	0
Total operating expenses	7,620	21,677	45,696	66,774
Loss from operations	(7,620)	(21,677)	(45,696)	(66,774)
Interest income	315	128	532	515
Other expense, net	(616)	(157)	(1,246)	(287)
Net loss before income tax benefit	(7,921)	(21,706)	(46,410)	(66,546)
Income tax benefit	0	0	284	0
Net loss	(7,921)	(21,706)	(46,126)	(66,546)
Other comprehensive income (loss):
Foreign currency translation adjustments	343	18	481	18
Unrealized gain (loss) on available for sales securities	(130)	(64)	(655)	(260)
Total comprehensive loss	$ (7,708)	$ (21,752)	$ (46,300)	$ (66,788)
Net loss per share - basic	$ (0.22)	$ (0.73)	$ (1.41)	$ (2.25)
Net loss per share - diluted	$ (0.22)	$ (0.73)	$ (1.41)	$ (2.25)
Weighted average shares of common stock outstanding - basic	35,612,749	29,767,376	32,758,132	29,637,328
Weighted average shares of common stock outstanding - diluted	35,612,749	29,767,376	32,758,132	29,637,328