CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Revenues, net:
Total revenues, net	$ 2,825	$ 3,039	$ 7,275	$ 7,514
Costs and expenses:
Cost of royalty revenues	62	151	186	376
Research and development	10,813	8,602	34,571	24,112
General and administrative	4,556	4,334	15,318	12,524
Total costs and expenses	15,431	13,087	50,075	37,012
Loss from operations	(12,606)	(10,048)	(42,800)	(29,498)
Other expense:
Interest income	335	54	577	158
Imputed interest expense related to the sale of future royalties	(1,023)	(1,057)	(3,120)	(3,366)
Other income (expense), net	0	0	0	890
Total other expense	(688)	(1,003)	(2,543)	(2,318)
Net loss	$ (13,294)	$ (11,051)	$ (45,343)	$ (31,816)
Net loss per common share (basic ) (in dollars per share)	$ (0.14)	$ (0.12)	$ (0.49)	$ (0.35)
Net loss per common share (diluted) (in dollars per share)	$ (0.14)	$ (0.12)	$ (0.49)	$ (0.35)
Weighted average common shares (basic) (in shares)	93,791,178	91,601,362	92,370,359	91,552,433
Weighted average common shares (diluted) (in shares)	93,791,178	91,601,362	92,370,359	91,552,433
Net loss	$ (13,294)	$ (11,051)	$ (45,343)	$ (31,816)
Other comprehensive income:
Unrealized gain (loss) on marketable securities	76	0	(370)	0
Comprehensive loss	(13,218)	(11,051)	(45,713)	(31,816)
Royalties
Revenues, net:
Total revenues, net	2,843	3,058	7,377	7,593
Other revenue
Revenues, net:
Total revenues, net	0	0	0	1
Contra revenue, net
Revenues, net:
Total revenues, net	$ (18)	$ (19)	$ (102)	$ (80)