Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Revenues	$ 0	$ 0
Operating expenses:
Research and development	12,555,000	11,535,000
General and administrative	3,690,000	2,693,000
Total operating expenses	16,245,000	14,228,000
Loss from operations	(16,245,000)	(14,228,000)
Other income (expense):
Amortization of financing costs	(12,000)	(21,000)
Interest income, net	154,000	239,000
Total other income, net	142,000	218,000
Net loss	(16,103,000)	(14,010,000)
Other comprehensive gain (loss), net of tax:
Unrealized loss on securities	(893,000)	(50,000)
Foreign currency translation gain	31,000	0
Comprehensive loss	$ (16,965,000)	$ (14,060,000)
Basic and diluted net loss per common share	$ (0.21)	$ (0.19)
Weighted-average shares used to compute basic and diluted net loss per share	77,413,141	74,782,427