Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenue:
Total revenue	$ 13,696		$ 13,696
Operating expenses:
Research and development	13,579	$ 16,869	25,434	$ 31,431
General and administrative	6,822	4,691	13,176	9,151
Total operating expenses	20,401	21,560	38,610	40,582
Loss from operations	(6,705)	(21,560)	(24,914)	(40,582)
Other income (expense):
Interest income	19	161	41	461
Other expense, net	(52)	(19)	(83)	(25)
Total other income (expense)	(33)	142	(42)	436
Loss before income tax expense	(6,738)	(21,418)	(24,956)	(40,146)
Income tax expense	(92)		(92)
Net loss	$ (6,830)	$ (21,418)	$ (25,048)	$ (40,146)
Net loss per share, basic and diluted	$ (0.10)	$ (0.40)	$ (0.38)	$ (0.93)
Weighted-average common shares outstanding, basic and diluted	65,631,906	52,941,603	65,618,207	43,019,670
License [Member]
Revenue:
Total revenue	$ 12,000		$ 12,000
Development Fee [Member]
Revenue:
Total revenue	$ 1,696		$ 1,696