Condensed Consolidated Statements of Operations - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Total revenues	$ 0	$ 74,000	$ 10,000	$ 128,000
Operating expenses:
Research and development	4,112,000	2,075,000	12,885,000	6,743,000
General and administrative	3,385,000	5,156,000	11,903,000	12,634,000
Total operating expenses	7,497,000	7,231,000	24,788,000	19,377,000
Loss from operations	(7,497,000)	(7,157,000)	(24,778,000)	(19,249,000)
Other income and expense:
Other income, net	7,000	6,322,000	19,000	6,482,000
Interest income	2,000	168,000	7,000	246,000
Interest expense	0	0	(37,000)	(48,000)
Other (expense) income, net	9,000	6,490,000	(11,000)	6,680,000
Net loss before taxes	(7,488,000)	(667,000)	(24,789,000)	(12,569,000)
Income tax benefit	0	2,432,000	0	9,321,000
Net income (loss)	(7,488,000)	1,765,000	(24,789,000)	(3,248,000)
Accretion of preferred stock to current redemption value	0	0	0	(651,000)
Net income (loss) attributable to common shareholders	$ (7,488,000)	$ 1,765,000	$ (24,789,000)	$ (3,899,000)
Net income (loss) per share of common stock
Net income (loss) per share of common stock - Basic (in dollars per share)	$ (0.90)	$ 0.21	$ (2.97)	$ (0.62)
Net income (loss) per share of common stock - Diluted (in dollars per share)	$ (0.90)	$ 0.21	$ (2.97)	$ (0.62)
Weighted average number of common shares outstanding
Weighted-average number of common shares outstanding - Basic (in shares)	8,357,391	8,293,312	8,333,017	6,267,576
Weighted-average number of common shares outstanding - Diluted (in shares)	8,357,391	8,486,804	8,333,017	6,267,576
Revenue, Product and Service [Extensible List]			License and collaboration revenue