STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows used in operating activities:
Net loss	$ (29,465)	$ (21,300)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	307	160
Noncash lease expense	411	282
Stock-based compensation	6,829	3,886
Amortization of premium and discount on marketable securities, net	748
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	93	761
Accounts payable	2	1,601
Accrued expenses and other liabilities	(401)	(1,372)
Operating lease liabilities	(419)	(161)
Net cash used in operating activities	(21,895)	(16,143)
Cash flows provided by (used in) investing activities:
Proceeds from maturities of marketable securities	42,500
Purchases of property and equipment	(952)	(986)
Net cash provided by (used in) investing activities	41,548	(986)
Cash flows provided by financing activities:
Proceeds from the sale of common stock, net of offering costs		161,424
Proceeds from the exercise of stock options	153	386
Net cash provided by financing activities	153	161,810
Net increase in cash and cash equivalents	19,806	144,681
Cash, cash equivalents, and restricted cash at beginning of period	35,872	218,309
Cash, cash equivalents, and restricted cash at end of period	55,678	362,990
Supplemental disclosures:
Operating lease right-of-use assets obtained in exchange for operating lease liabilities	928
Property and equipment in accounts payable	354	$ 86
Unrealized loss on marketable securities	$ (1,602)