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	$ (6,281)	$ (4,786)
Adjustments to reconcile net loss to net cash used in operating activities
Compensation cost for stock options granted	1,573	1,806
Depreciation and amortization	3	2
Changes in operating assets and liabilities:
Prepaid expenses	(1,264)	(1,386)
Research and development tax rebate receivable	5	404
Other current assets	1,565	(114)
Other assets	1	0
Accounts payable	(1,521)	(121)
Accrued expenses	(446)	(84)
Payroll liabilities	(703)	(591)
Other current liabilities	46	(8)
Net cash used in operating activities	(7,022)	(4,878)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of furniture and equipment	0	(13)
Net cash used in investing activities	0	(13)
CASH FLOWS FROM FINANCING ACTIVITIES
Net cash provided by financing activities	0	0
NET DECREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(7,022)	(4,891)
CASH, CASH EQUIVALENTS AND RESTRICTED CASH, BEGINNING BALANCE	111,000	136,487
CASH, CASH EQUIVALENTS AND RESTRICTED CASH, ENDING BALANCE	103,978	131,596
SUPPLEMENTAL DISCLOSURES
Cash and cash equivalents	103,868	131,486
Restricted cash	110	110
Total cash, cash equivalents and restricted cash shown in the Condensed Consolidated Statements of Cash Flows	$ 103,978	$ 131,596