STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash flows used in operating activities:
Net loss	$ (111,694)	$ (56,929)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	915	542
Noncash lease expense	1,328
Loss on disposal of property and equipment		11
Stock-based compensation	20,931	5,583
Amortization of premium and discount on marketable securities, net	1,364
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(1,382)	(1,155)
Accounts payable	3,903	1,157
Accrued expenses and other liabilities	2,463	4,614
Operating lease liabilities	(1,359)
Net cash used in operating activities	(83,531)	(46,177)
Cash flows used in investing activities:
Purchases of marketable securities	(261,480)
Purchases of property and equipment	(2,323)	(621)
Net cash used in investing activities	(263,803)	(621)
Cash flows provided by financing activities:
Proceeds from the sale of common stock, net of offering costs	161,424
Proceeds from the issuance of common stock upon initial public offering, net of offering costs		166,630
Payment of offering costs	(303)	(12)
Payment of capital lease obligation		(258)
Proceeds from issuance of common stock in connection with the exercise of stock options	3,504	100
Proceeds from the issuance of common stock under ESPP	272
Net cash provided by financing activities	164,897	246,228
Net (decrease) increase in cash and cash equivalents	(182,437)	199,430
Cash, cash equivalents and restricted cash at beginning of year	218,309	18,879
Cash, cash equivalents and restricted cash at end of year	35,872	218,309
Supplemental disclosures:
Operating lease right-of-use assets obtained in exchange for operating lease liabilities	567
Property and equipment in accounts payable	806	765
Unrealized gain (loss) on marketable securities	$ (711)
Offering costs in accrued expenses		265
Offering costs in accounts payable		24
Series C Convertible Preferred Stock
Cash flows provided by financing activities:
Proceeds from the sale of convertible preferred stock, net of offering costs		49,826
Series B Convertible Preferred Stock
Cash flows provided by financing activities:
Proceeds from the sale of convertible preferred stock, net of offering costs		$ 29,942