Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (65,952)	$ (47,252)
Adjustments to reconcile net loss to net cash used in operating activities:
Loss on impairment of goodwill	29,517
Stock based compensation	6,688	10,362
Operating lease right-of-use asset	1,366	1,050
Depreciation	248	117
Amortization of premium on marketable debt securities	1,137	1,737
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	265	(418)
Other assets	222	295
Accounts payable	631	40
Accrued expenses	748	576
Operating lease liabilities	(1,327)	(1,009)
Net cash used in operating activities	(26,457)	(34,502)
Cash flows from investing activities:
Purchase of marketable debt securities	(43,550)	(124,748)
Proceeds from maturity and redemption of marketable debt securities	58,620	27,150
Purchase of property and equipment	(120)	(596)
Net cash (used in)/provided by investing activities	14,950	(98,194)
Cash flows from financing activities:
Repurchase of shares in connection with settlement of RSUs	(90)	(228)
Net cash (used in)/provided by financing activities	(90)	(228)
Net (decrease)/increase in cash and cash equivalents and restricted cash	(11,597)	(132,924)
Cash and cash equivalents and restricted cash - beginning of year	36,469	169,393
Cash and cash equivalents and restricted cash - end of period	24,872	36,469
Cash paid for:
Interest
Income Taxes