CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (32,829)	$ (19,423)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	189	159
Non-cash lease cost	221	199
Share-based compensation	3,203	2,009
Unrealized foreign currency transaction (gain) loss	(11)	(19)
Change in fair value of derivative liability	193		$ (800)
Accretion of discount on marketable securities	23	64
Non-cash interest expense associated with the sale of future royalties	2,488
Changes in operating assets and liabilities:
Other receivables	660	(3,218)
Prepaid expenses and other current assets	31	869
Tax incentive receivables	1	772
Other assets	(285)
Accounts payable	3,679	2,689
Accrued expenses and other current liabilities	(5,290)	624
Deferred revenue, current and non-current	(246)
Other long-term liabilities	(10)	(9)
Operating lease liability	(240)	(195)
Net cash used in operating activities	(28,223)	(15,479)
Cash flows from investing activities:
Purchases of marketable securities	(26,970)	(2,997)
Proceeds from maturities of marketable securities	10,906	6,000
Net cash provided by (used in) investing activities	(16,064)	3,003
Cash flows from financing activities:
Proceeds from Issuance of Common Stock	3,626	4,253
Payment of offering and financing costs		(37)
Proceeds from stock option exercises	188	93
Net cash provided by financing activities	3,814	4,309
Net increase (decrease) in cash and cash equivalents	(40,473)	(8,167)
Cash, cash equivalents and restricted cash at beginning of period	112,584	85,209	85,209
Cash, cash equivalents and restricted cash at end of period	72,111	77,042	$ 112,584
Supplemental disclosure of non-cash activities:
Offering and financing costs in accounts payable and accruals	$ 0	$ 93