Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net loss	$ (7,915)	$ (6,867)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	30	32
Stock-based compensation	499	527
License rights expense settled in stock	772	0
Change in fair value of warrant liability	(39)	(160)
Operating lease, net	110	90
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	427	438
Accounts payable	(156)	860
Accrued expenses and other current liabilities	255	275
Net cash used in operating activities	(6,017)	(4,805)
Cash flows from investing activities:
Purchase of fixed assets	0	(6)
Net cash used in investing activities	0	(6)
Cash flows from financing activities:
Proceeds from sale of common stock, net of issuance costs	141	0
Net cash provided by financing activities	141	0
Effect of exchange rate changes on cash and cash equivalents	(4)	12
Net decrease in cash and cash equivalents	(5,880)	(4,799)
Cash and cash equivalents, - beginning of period	43,145	70,903
Cash and cash equivalents, - end of period	$ 37,265	$ 66,104