Condensed Statements of Cash Flows - USD ($)	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows used in operating activities
Net loss	$ (7,706,000)	$ (7,222,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation, net of forfeitures	630,000	233,000
Depreciation and amortization	518,000	568,000
Issuance of common stock for services	0	80,000
Derivative gain	(4,217,000)	(267,000)
Changes in operating assets and liabilities:
Increase in prepaid expenses and other	(15,000)	(1,211,000)
(Decrease) increase in accounts payable and accrued expenses	(53,000)	1,386,000
Decrease in lease liability	(48,000)	(42,000)
Net cash used in operating activities	(10,891,000)	(6,475,000)
Cash flows used in investing activities
Purchase of fixed assets	0	(81,000)
Net cash used in investing activities	0	(81,000)
Cash flows from financing activities
Proceeds from sale of common stock in connection with the "at-the-market" equity offering program	0	9,972,000
Costs related to sale of common stock in connection with the "at-the-market" equity offering program	0	(447,000)
Proceeds from sale of common stock and warrants in connection with the registered direct offering	0	234,000
Costs related to the sale of common stock and warrants in connection with the registered direct offering	(32,000)	0
Shares held back in settlement of tax obligation for shares issued in connection with restricted stock awards	(79,000)	0
Net cash (used in) provided by financing activities	(111,000)	9,759,000
Net change in cash and cash equivalents	(11,002,000)	3,203,000
Cash and cash equivalents at beginning of period	33,892,000	17,346,000
Cash and cash equivalents at end of period	22,890,000	20,549,000
Non-cash transactions:
Commercial insurance premium financing agreement	$ 1,159,000	$ 1,016,000