Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net loss	$ (8,127)	$ (8,961)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	466	45
Stock-based compensation	770	2,443
Non-cash lease expense	174	170
Non-cash expense related to equity consideration for a service agreement	0	494
Unrealized gain on foreign exchange rate changes	(236)	(109)
Changes in assets and liabilities:
Prepaid expenses and other current assets	239	337
Accounts payable	31	(222)
Accrued expenses	151	(69)
Operating lease liabilities	(183)	(176)
Net cash used in operating activities	(6,715)	(6,048)
Cash flows from investing activities:
Purchase of property and equipment	(3)	0
Net cash used in investing activities	(3)	0
Cash flows from financing activities:
Proceeds from issuance of common stock and warrants, net of issuance costs	0	27,390
Proceeds from ATM Program, net of issuance costs	205	570
Principal payments on loans payable	(294)	(352)
Net cash (used in) provided by financing activities	(89)	27,608
Net (decrease) increase in cash, cash equivalents, and restricted cash	(6,807)	21,560
Cash, cash equivalents, and restricted cash - beginning of period	22,502	17,084
Cash, cash equivalents, and restricted cash - end of period	15,695	38,644
Operating lease liabilities arising from obtaining right-of-use assets	$ 0	$ 2,000