Condensed Consolidated Statements of Operations - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Consolidated Statements of Operations [Abstract]
Grant revenue	$ 1,338,000	$ 1,251,000	$ 4,457,000	$ 3,485,000
Operating expenses
Research and development	8,400,000	5,626,000	25,448,000	15,201,000
General and administrative	1,561,000	1,768,000	5,627,000	6,058,000
Total operating expenses	9,961,000	7,394,000	31,075,000	21,259,000
Loss from operations	(8,623,000)	(6,143,000)	(26,618,000)	(17,774,000)
Other income (expense)
Gain upon extinguishment of Paycheck Protection Program loan		726,000		726,000
Interest income	9,000		15,000	4,000
Interest expense		(2,000)		(64,000)
Total other income (expense), net	9,000	724,000	15,000	666,000
Net loss	$ (8,614,000)	$ (5,419,000)	$ (26,603,000)	$ (17,108,000)
Net Loss per Share
Net loss per share, basic	$ (0.24)	$ (0.22)	$ (0.79)	$ (0.73)
Net loss per share, diluted	$ (0.24)	$ (0.22)	$ (0.79)	$ (0.73)
Weighted average shares outstanding, basic	36,038,686	24,820,233	33,704,071	23,363,113
Weighted average shares outstanding, diluted	36,038,686	24,820,233	33,704,071	23,363,113