UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue:
Collaboration revenue	$ 0	$ 2,016,000	$ 0	$ 7,052,000
Total revenue	0	2,016,000	0	7,052,000
Operating expenses:
Research and development expense	0	4,805,000	1,423,000	18,694,000
General and administrative expense	2,397,000	2,416,000	11,155,000	8,783,000
Loss from sale of property and equipment	920,000	0	920,000	0
Total operating expenses	3,317,000	7,221,000	13,498,000	27,477,000
Operating loss	(3,317,000)	(5,205,000)	(13,498,000)	(20,425,000)
Other income (expense), net:
Change in fair value of investment in convertible notes receivable	(2,000,000)	0	(2,000,000)	0
Dividend income	13,000	41,000	45,000	59,000
Interest income	4,000	4,000	28,000	7,000
Interest expense	0	0	0	(595,000)
Other income (expense), net	44,000	0	(2,000)	(24,000)
Total other income (expense), net	(1,939,000)	45,000	(1,929,000)	(553,000)
Net loss before provision for income taxes	(5,256,000)	(5,160,000)	(15,427,000)	(20,978,000)
Provision for income taxes	0	0	0	0
Net loss	$ (5,256,000)	$ (5,160,000)	$ (15,427,000)	$ (20,978,000)
Basic loss per common share (in dollars per share)	$ (0.61)	$ (1.04)	$ (1.98)	$ (4.66)
Diluted loss per common share (in dollars per share)	$ (0.61)	$ (1.04)	$ (1.98)	$ (4.66)
Weighted-average basic common shares outstanding (in shares)	8,650,402	4,963,344	7,799,233	4,502,962
Weighted-average diluted common shares outstanding (in shares)	8,650,402	4,963,344	7,799,233	4,502,962