CONDENSED STATEMENT OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities
Net loss	$ (63,261)	$ (73,464)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation expense	10,729	2,657
Depreciation and amortization	1,200	503
Accretion and amortization of premiums and discounts on investments, net	2,410	116
Non-cash lease expense	324	220
Change in fair value of preferred stock purchase right liability		40,163
Others		(15)
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(3,688)	(3,355)
Accounts payable and accrued and other liabilities	1,931	2,523
Net cash used in operating activities	(50,355)	(30,652)
Cash flows from investing activities
Purchases of property and equipment	(3,932)	(6,442)
Purchases of short-term investments	(131,109)	(144,916)
Maturities of short-term investments	185,410	20,000
Net cash provided by (used in) investing activities	50,369	(131,358)
Cash flows from financing activities
Proceeds from issuance of convertible preferred stock, net of issuance costs		64,321
Proceeds from initial public offering, net of issuance costs		265,461
Proceeds from stock option exercises	1,330	322
Proceeds from early exercise of stock options		12
Payments of deferred offering costs	(130)
Net cash provided by financing activities	1,200	330,116
Net increase in cash and cash equivalents	1,214	168,106
Cash, cash equivalents, and restricted cash beginning of period	97,105	20,875
Cash, cash equivalents, and restricted cash end of period	98,319	188,981
Reconciliation of cash, cash equivalents and restricted cash to the balance sheet:
Cash and cash equivalents	96,221	188,568
Restricted cash	2,098	413
Total cash, cash equivalents and restricted cash	$ 98,319	$ 188,981