Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows used in operating activities:
Net loss	$ (59,032)	$ (43,551)
Adjustments to reconcile net loss to cash used in operating activities:
Stock-based compensation expense	17,086	9,073
Depreciation expense	740	839
Reduction in carrying amount of right-of-use asset	2,890	647
Accretion of discount on marketable securities	1,082	474
Amortization of debt discount − related party	354	360
Changes in operating assets and liabilities:
Accounts receivable	4,007	(1,729)
Prepaid expenses and other current and long-term assets	1,722	(1,181)
Accounts payable	(564)	(1,338)
Accrued expenses and other current liabilities	(87)	316
Operating lease liability	(983)	(508)
Deferred revenue	(16,006)	(6,338)
Net cash used in operating activities	(48,791)	(42,936)
Cash flows provided by (used in) investing activities:
Proceeds from maturities of marketable securities	138,057	209,494
Purchases of marketable securities	(108,132)	(237,622)
Purchases of property and equipment	(701)	(1,168)
Net cash provided by (used in) investing activities	29,224	(29,296)
Cash flows provided by financing activities:
Proceeds from follow-on offering, net of issuance costs paid of $10.8 million (Note 10)	0	169,934
Proceeds from exercises of stock options	519	705
Payment of initial public offering costs	0	(286)
Other	220	(3)
Net cash provided by financing activities	739	170,350
Net change in cash, cash equivalents and restricted cash	(18,828)	98,118
Cash, cash equivalents and restricted cash at beginning of period	79,403	184,304
Cash, cash equivalents and restricted cash at end of period	60,575	282,422
Reconciliation of cash, cash equivalents and restricted cash:
Cash, cash equivalents and restricted cash at end of period	60,575	282,422
Less: restricted cash	(3,279)	(1,276)
Cash and cash equivalents at end of the period	57,296	281,146
Supplemental disclosures of cash flow information:
Cash paid for interest − related party	828	707
Supplemental disclosures of non-cash investing and financing activities:
Operating lease liabilities arising from obtaining right-of-use assets	44,067	0
Capital expenditures in accounts payable and accrued expenses	3,270	0
Follow-on costs in accounts payable and accrued expenses	0	451
Aggregate exercise price of warrant net exercised - related party (Note 10)	$ 0	$ 3,002