Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net loss	$ (21,171)	$ (12,715)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	54	35
Non-cash gain on foreign currency remeasurement	(219)	(171)
Non-cash share-based compensation	3,128	1,666
Non-cash lease expenses	550	269
Changes in operating assets and liabilities
Prepaid expenses and other current assets	(1,386)	(2,751)
Deferred and prepaid tax assets	(135)	0
Other assets	(311)	7
Operating lease liabilities	(538)	(269)
Accounts payable	(445)	2,432
Accrued expenses and other liabilities	(2,650)	(2,281)
Net cash used in operating activities	(23,123)	(13,778)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(82)	(70)
Net cash used in investing activities	(82)	(70)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from exercise of options	189	998
Preferred shares issuance costs	0	(40)
Net cash provided by financing activities	189	958
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(6,543)	2,083
Net decrease in cash, cash equivalents and restricted cash	(29,559)	(10,807)
Cash, cash equivalents and restricted cash, beginning of the period	273,347	190,356
Cash, cash equivalents and restricted cash, end of the period	243,788	179,549
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Proceeds from exercise of options not yet received and recorded in other current assets	208	0
Deferred offering costs included in prepaid expenses and other current assets	835	524
Right-of-use assets obtained in exchange for new operating lease liabilities	0	1,049
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	243,684	179,520
Short-term restricted cash	104	29
Total cash, cash equivalents and restricted cash	$ 243,788	$ 179,549