Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows used in operating activities:
Net loss	$ (31,620)	$ (20,971)
Adjustments to reconcile net loss to cash used in operating activities:
Stock-based compensation expense	8,938	3,845
Depreciation expense	305	451
Reduction in carrying amount of right-of-use asset	1,184	320
Accretion of discount on marketable securities	664	102
Amortization of debt discount − related party	176	182
Changes in operating assets and liabilities:
Accounts receivable	3,944	828
Prepaid expenses and other current and long-term assets	309	(40)
Accounts payable	(1,152)	(1,965)
Accrued expenses and other current liabilities	(3,766)	(3,666)
Operating lease liability	304	(251)
Deferred revenue	(5,882)	(3,769)
Net cash used in operating activities	(26,596)	(24,934)
Cash flows used in investing activities:
Proceeds from maturities of marketable securities	72,387	114,994
Purchases of marketable securities	(76,219)	(176,303)
Purchases of property and equipment	(172)	(421)
Net cash used in investing activities	(4,004)	(61,730)
Cash flows provided by (used in) financing activities:
Proceeds from exercises of stock options	260	166
Payment of initial public offering costs		(314)
Other	220	(3)
Net cash provided by (used in) financing activities	480	(151)
Net change in cash, cash equivalents and restricted cash	(30,120)	(86,815)
Cash, cash equivalents and restricted cash at beginning of period	79,403	184,304
Cash, cash equivalents and restricted cash at end of period	49,283	97,489
Reconciliation of cash, cash equivalents and restricted cash:
Cash, cash equivalents and restricted cash at end of period	49,283	97,489
Less: restricted cash	(3,279)	(2,577)
Cash and cash equivalents at end of the period	46,004	94,912
Supplemental disclosures of cash flow information:
Cash paid for interest − related party	473	358
Supplemental disclosures of non-cash investing and financing activities:
Operating lease liabilities arising from obtaining right-of-use assets	44,067
Capital expenditures in accounts payable and accrued expenses	$ 52	$ 722