Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net loss	$ (38,587)	$ (30,634)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	529	69
Stock-based compensation expense	5,850	4,175
Amortization of operating leases, right-of-use assets	194	491
Change in fair value of CVR liability	(1,700)
Net amortization (accretion) of premiums (discounts) on marketable securities	(1,043)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(316)	(737)
Other assets	(30)	(1,879)
Accounts payable	(1,670)	532
Accrued expenses and other current liabilities	(2,557)	199
Operating lease liability	(187)	(550)
Net cash used in operating activities	(39,517)	(28,334)
Cash flows from investing activities:
Purchases of property and equipment	(1,103)	(441)
Purchases of marketable securities	(59,013)
Maturities and sales of marketable securities	120,000
Net cash (used in) provided by investing activities	59,884	(441)
Cash flows from financing activities:
Proceeds from issuance of stock from employee stock purchase plan	313	129
Proceeds from issuance of common stock upon stock option exercises	132	9
Net cash provided by financing activities	445	138
Net (decrease) increase in cash, cash equivalents and restricted cash	20,812	(28,637)
Cash, cash equivalents and restricted cash at beginning of period	141,141	220,939
Cash, cash equivalents and restricted cash at end of period	161,953	192,302
Supplemental disclosure of cash flow information:
Right-of-use assets obtained in exchange for new operating lease liabilities		917
Supplemental disclosure of noncash investing and financing information:
Property & equipment included in accounts payable and accrued expenses	674
Conversion of Series A Convertible Preferred stock into common shares	$ 3,520	$ 7,000