CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (84,713)	$ (97,090)
Adjustments to reconcile net loss to net cash used in operating activities:
Change in fair value of contingent consideration liability	86	700
Impairment loss on construction-in-progress		11,370
Impairment loss on intangible assets		579
Stock-based compensation expense	8,101	5,519
Depreciation and amortization	(205)	551
Loss on foreign currency exchange	34	384
Changes in operating assets and liabilities:
Accounts receivable	256	4,181
Prepaid expenses and other assets	2,650	(5,908)
Accounts payable	2,770	1,422
Accrued expenses and other liabilities	5,393	(2,299)
Income tax and R&D incentive receivables	3,042	2,353
Net cash used in operating activities	(62,586)	(78,238)
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from sales and maturities of short-term investments		107,427
Purchases of short-term investments	(73,273)	(7,592)
Purchases of property and equipment, net	(126)	(12,117)
Cash paid for internally developed patents		(195)
Net cash (used in) provided by investing activities	(73,399)	87,523
CASH FLOWS FROM FINANCING ACTIVITIES:
Payments of deferred offering costs		(118)
Proceeds from issuance of common stock in at-the-market offerings, net	56,166	64,815
Proceeds from issuance of common stock from Employee Stock Purchase Plan	181	225
Proceeds from exercises of stock options, net	434	176
Net cash provided by financing activities	56,781	65,098
Net (decrease) increase in cash and cash equivalents and restricted cash	(79,204)	74,383
Cash, cash equivalents and restricted cash at beginning of period	190,335	115,952
Cash, cash equivalents and restricted cash at end of period	111,131	190,335
SUPPLEMENTAL NON-CASH ACTIVITIES:
Fair value of common stock retired in exchange for issuance of common stock warrant		17,200
Common stock issued related to contingent consideration liability	$ 6,176
Operating lease liability and right of use asset addition		$ 72