CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cash flow from operating activities
Net loss	$ (3,324)	$ (1,512)
Adjustments to reconcile net loss to net cash used in operating activities
Stock-based compensation	170	157
Amortization of right of use assets	19	28
Depreciation	18	66
(Increase) decrease in operating assets
Prepaid drug product for testing	12	(95)
Other current assets	250	(570)
Increase (decrease) in operating liabilities
Accounts payable and accrued expenses	341	(54)
Lease liabilities	(21)	(28)
Net cash used in operating activities	(2,535)	(2,008)
Cash flow from financing activities
Net proceeds from sale of common stock	0	19,411
Net proceeds from exercise of warrants	0	869
Net cash provided by financing activities	0	20,280
Net increase (decrease) in cash	(2,535)	18,272
Cash, beginning of period	20,426	1,004
Cash, end of period	$ 17,891	$ 19,276

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