Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net loss	$ (9,895)	$ (9,074)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	44	46
Amortization of operating lease right-of-use assets	328	283
Share-based compensation expense	315	215
Changes in operating assets and liabilities:
Prepaid expenses	52	14
Accounts payable	124	(461)
Operating lease liability	(339)	(294)
Accrued expenses and other liabilities	517	(263)
Net cash used in operating activities	(8,854)	(9,534)
Cash flows from investing activities:
Purchases of property and equipment	(77)	(41)
Net cash used in investing activities	(77)	(41)
Cash flows from financing activities:
Proceeds from exercise of warrants	8,509	343
Proceeds from issuance of common stock and warrants, net of commissions and issuance costs		22,119
Net cash provided by financing activities	8,509	22,462
Increase / (decrease) in cash and cash equivalents and restricted cash	(422)	12,887
Cash, cash equivalents and restricted cash at end of period	19,181	19,603
Cash, cash equivalents and restricted cash at beginning of period	19,603	6,716
Supplemental disclosure of cash flow information and non-cash investing and financing activities:
Fair value of warrants issued in connection with financing activities		15,194
Right-of-use assets and lease liability recorded upon adoption of ASC 842	629
Restricted cash included in other non-current assets	150	110
Cash and cash equivalents	19,031	19,493
Total cash, cash equivalents and restricted cash shown in the statement of cash flows	$ 19,181	$ 19,603