Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating activities:
Net loss	$ (5,078,000)	$ (3,739,000)
Adjustments required to reconcile net loss to net cash used in operating activities:
Depreciation	295,000	348,000
Stock-based compensation	1,044,000
Non-cash interest expense	159,000	306,000
Change in fair value of derivative liability		40,000
Changes in operating assets and liabilities:
Award receivable	(1,000,000)
Accounts payable and accrued liabilities	(195,000)	429,000
Accrued compensation	(114,000)
Deferred rent and lease liabilities, net	(122,000)	(84,000)
Deferred award liability	859,000
Prepaid expenses and other current assets	(80,000)	241,000
Net cash used in operating activities	(4,232,000)	(2,459,000)
Investing activities:
Purchases of property and equipment	(104,000)	(142,000)
Net cash used in investing activities	(104,000)	(142,000)
Financing activities:
Payment of deferred consideration for asset acquisition	(1,000,000)	(1,000,000)
Proceeds from sale of common stock, net of offering costs	23,331,000
Proceeds from exercises of warrants	81,000
Net cash provided by (used in) financing activities	22,412,000	(1,000,000)
Net increase (decrease) in cash, cash equivalents and restricted cash	18,076,000	(3,601,000)
Cash, cash equivalents and restricted cash, beginning of period	6,733,000	10,463,000
Cash, cash equivalents and restricted cash, end of period	24,809,000	$ 6,862,000
Supplemental schedule of non-cash investing and financing activities:
Property and equipment included in accounts payable	9,000
Unpaid offering costs	$ 471,000