Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net loss	$ (1,150)	$ (1,359)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash stock-based compensation	270	344
Depreciation and amortization	14	17
Gain on sale of property and equipment	(100)
Changes in operating assets and liabilities:
Other current assets	(9)	93
Accounts payable	155	201
Accrued development expense	(390)	87
Accrued compensation and benefits	14	1
Other current liabilities	2	12
Net cash used in operating activities	(1,194)	(604)
Cash flows from investing activities:
Purchases of property and equipment		(18)
Proceeds from sale of property and equipment	100
Net cash provided by / (used in) investing activities	100	(18)
Cash flows from financing activities:
Issuance costs from 2018 sale of common stock and warrants		(60)
Proceeds from exercise of common stock warrants, net	3,613
Net cash provided by / (used in) financing activities	3,613	(60)
Net increase / (decrease) in cash and cash equivalents	2,519	(682)
Cash and cash equivalents at beginning of period	23,081	19,807
Cash and cash equivalents at end of period	$ 25,600	$ 19,125