Consolidated Statements of Operations - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating expenses
Research and development	$ 17,334,000	$ 15,083,000
General and administrative	14,043,000	12,608,000
Total operating expenses	31,377,000	27,691,000
Operating loss	(31,377,000)	(27,691,000)
Impairment charge on investment in equity securities	(2,990,000)	0
Interest income	4,343,000	877,000
Other expense, net	(70,000)	(146,000)
Loss before income taxes	(30,094,000)	(26,960,000)
Income taxes benefit	0	0
Net loss	$ (30,094,000)	$ (26,960,000)
Net loss per share of common stock - basic (in dollars per share)	$ (0.24)	$ (0.21)
Net loss per share of common stock - diluted (in dollars per share)	$ (0.24)	$ (0.21)
Weighted average shares outstanding used to compute net loss per share- basic (in shares)	126,081,602	126,624,110
Weighted average shares outstanding used to compute net loss per share - diluted (in shares)	126,081,602	126,624,110