Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Net income (loss)	$ (15,343)	$ (7,435)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	1,745	539
Depreciation expense	98	39
Non-cash lease expense	383	166
Changes in operating assets and liabilities:
Prepaid expenses and other assets	1,789	81
Accounts payable	(674)	724
Accrued expenses and other current liabilities	(2,031)	(1,331)
Right of use assets and operating lease liability	82	(159)
Other liabilities	0	50
Net cash used in operating activities	(13,951)	(7,326)
Investing activities:
Purchases of property and equipment	(28)	(13)
Net cash used in investing activities	(28)	(13)
Financing activities:
Deferred financing costs	0	(559)
Proceeds from stock option exercises	159	21
Net cash provided by (used in) financing activities	159	(538)
Net decrease in cash and cash equivalents	(13,820)	(7,877)
Cash, cash equivalents and restricted cash—beginning of period	158,830	92,777
Cash, cash equivalents and restricted cash—end of period	145,010	84,900
Non-cash investing and financing activities:
Non-cash accretion of Series A and Series B redeemable convertible preferred stock	0	95,016
Stock option exercise receivables in prepaid expenses and other current assets	(30)	0
Issuance costs in accounts payable and accrued expenses	0	560
Purchases of property and equipment in accounts payable and accrued expenses	$ 1,552	$ 130