Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash flows from operating activities
Net Loss	$ (46,126)	$ (66,546)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash rent expense	0	199
Stock based compensation	14,986	21,360
Depreciation and amortization	162	260
Impairment loss on operating lease	136	0
Loss on disposal of fixed assets	77	0
Non-cash goodwill impairment charge	825	0
Amortization of premium on available for sale investments	83	679
Change in deferred tax liabilities due to acquisition of Novosteo, Inc.	(284)	0
Change in deferred tax liabilities due to acquisition of Novosteo, Inc.
Prepaid expenses and other current assets	2,396	(973)
Other assets	175	(154)
Accounts payable	(5,329)	(675)
Accrued expenses and other current liabilities	(5,304)	(2,664)
Net cash used in operating activities	(38,203)	(48,514)
Cash flow from investing activities:
Purchase of investments	(66,767)	(35,778)
Proceeds from maturities of investments	55,495	73,947
Cash acquired from Novosteo, Inc.	10,593	0
Proceeds from disposal of assets	70	0
Purchase of property and equipment	(55)	(136)
Net cash provided by / (used in) investing activities	(664)	38,033
Cash flows from financing activities:
Payments of finance leases	(31)	0
Proceeds from issuance of common stock upon exercise of stock options	148	5,818
Proceeds from issuance of common stock in connection with open market sales agreement, net of issuance costs	608	0
Net cash provided by financing activities	725	5,818
Effect of exchange rate changes on cash	227	29
Net decrease in cash and cash equivalents	(37,915)	(4,634)
Cash and cash equivalents at beginning of period	69,724	66,841
Cash and cash equivalents at end of period	31,809	62,207
Supplemental disclosures of non-cash information:
Net assets acquired of Novosteo, Inc. in exchange for common stock	16,503	0
Right-of-use assets obtained in exchange for new operating lease liabilities	256	1,254
Right-of-use asset and operating lease liability reduction as a result of lease modification	$ (640)	$ 0