Condensed Consolidated Statements of Operations - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Consolidated Statements of Operations [Abstract]
Grant revenue	$ 1,883,000	$ 1,168,000	$ 3,119,000	$ 2,234,000
Operating expenses
Research and development	9,020,000	5,225,000	17,048,000	9,575,000
General and administrative	2,083,000	2,139,000	4,066,000	4,290,000
Total operating expenses	11,103,000	7,364,000	21,114,000	13,865,000
Loss from operations	(9,220,000)	(6,196,000)	(17,995,000)	(11,631,000)
Other income (expense)
Interest income	5,000	2,000	6,000	4,000
Interest expense				(62,000)
Total other income (expense), net	5,000	2,000	6,000	(58,000)
Net loss	$ (9,215,000)	$ (6,194,000)	$ (17,989,000)	$ (11,689,000)
Net Loss per Share
Net loss per share, basic	$ (0.26)	$ (0.25)	$ (0.55)	$ (0.52)
Net loss per share, diluted	$ (0.26)	$ (0.25)	$ (0.55)	$ (0.52)
Weighted average shares outstanding, basic	35,999,642	24,762,818	32,517,416	22,622,477
Weighted average shares outstanding, diluted	35,999,642		32,517,416	22,622,477