Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net loss	$ (5,976)	$ (6,777)	$ (13,891)	$ (13,644)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	31	34	61	66
Stock-based compensation			1,012	1,041
License rights expense settled in stock			772	0
Change in fair value of warrant liability	(36)	(603)	(75)	(763)
Operating lease, net			104	84
Changes in operating assets and liabilities:
Prepaid expenses and other current assets			(757)	(1,729)
Accounts payable			2,041	1,820
Accrued expenses and other current liabilities			(410)	319
Net cash used in operating activities			(11,143)	(12,806)
Cash flows from investing activities:
Purchase of fixed assets			(15)	(67)
Net cash used in investing activities			(15)	(67)
Cash flows from financing activities:
Payment of tax liability for vested restricted stock units			(21)	(12)
Proceeds from sale of common stock, net of issuance costs			211	0
Net cash (used in) provided by financing activities			190	(12)
Effect of exchange rate changes on cash and cash equivalents			(5)	(19)
Net decrease in cash and cash equivalents			(10,973)	(12,904)
Cash and cash equivalents, - beginning of period			43,145	70,903
Cash and cash equivalents, - end of period	$ 32,172	$ 57,999	$ 32,172	$ 57,999