CONDENSED STATEMENT OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities
Net loss	$ (25,987)	$ (19,373)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation expense	4,097	3,347
Depreciation and amortization	610	301
Accretion and amortization of premiums and discounts on investments, net	727	758
Non-cash lease expense	1,380	137
Changes in operating assets and liabilities:
Prepaid expenses and other assets	1,460	825
Operating lease right-of-use assets	1,319
Operating lease liabilities	295
Accounts payable and accrued and other liabilities	(2,159)	(642)
Net cash used in operating activities	(18,258)	(14,647)
Cash flows from investing activities
Purchases of property and equipment	(1,770)	(1,033)
Purchases of short-term investments	(28,472)	(35,161)
Maturities of short-term investments	29,216	16,000
Net cash used in investing activities	(1,026)	(20,194)
Cash flows from financing activities
Proceeds from stock option exercises	79	756
Proceeds from early exercise of stock options		1
Net cash provided by financing activities	79	757
Net increase in cash and cash equivalents	(19,205)	(34,084)
Cash, cash equivalents, and restricted cash beginning of period	62,914	97,105
Cash, cash equivalents, and restricted cash end of period	43,709	63,021
Reconciliation of cash, cash equivalents and restricted cash to the balance sheet:
Cash and cash equivalents	41,611	62,608
Restricted cash	2,098	413
Total cash, cash equivalents and restricted cash	$ 43,709	$ 63,021