Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities
Net (loss) income	$ (5,179,000)	$ (5,812,000)
Adjustments to reconcile net (loss) income to net cash used in operating activities
Stock-based compensation, net	213,000	28,000
Depreciation and amortization	295,000	365,000
Issuance of common stock for services	80,000	60,000
Derivative loss (gain)	(831,000)	3,160,000
Changes in operating assets and liabilities
Increase in prepaid expenses and other	698,000	(180,000)
Increase (decrease) in accounts payable and accrued expenses	189,000	(5,000)
Decrease in lease liability	(18,000)	(56,000)
Net cash used in operating activities	(4,553,000)	(2,440,000)
Cash flows used in investing activities
Purchase of fixed assets	0	(5,000)
Net cash used in investing activities	0	(5,000)
Cash flows from financing activities
Proceeds from sale of common stock in connection with the equity distribution agreement	682,000	0
Costs related to sale of common stock in connection with the equity distribution agreement	(246,000)	0
Proceeds from warrant exercises	0	20,000
Net cash provided by financing activities	436,000	20,000
Net change in cash and cash equivalents	(4,117,000)	(2,425,000)
Cash and cash equivalents at beginning of period	6,532,000	7,585,000
Cash and cash equivalents at end of period	2,415,000	5,160,000
Non-cash transactions:
Initial lease liability arising from the adoption of ASU 2016-02	0	1,704,000
Initial recognition of right-of-use asset arising from the adoption of ASU 2016-02	$ 0	$ 1,168,000