Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 62,568	$ 128,965
Marketable securities	151,190	186,808
Prepaid expenses and other current assets	1,509	1,726
Prepaid research and development	7,257	7,567
Total current assets	222,524	325,066
Property and equipment, net	22,918	23,806
Right of use assets - operating leases	19,890
Other assets	4,720	6,204
Total assets	270,052	355,076
Current liabilities:
Accounts payable	4,506	9,448
Accrued expenses and other current liabilities	13,861	20,050
Operating lease liabilities	3,252
Total current liabilities	21,619	29,498
Operating lease liabilities - noncurrent	24,037
Deferred rent		6,921
Total liabilities	45,656	36,419
Commitments and Contingencies (note 9)
Stockholders' equity:
Common stock, $0.0001 par value: 300,000,000 shares authorized; 54,546,596 shares issued and outstanding at September 30, 2022 and 54,244,996 shares issued and outstanding at December 31, 2021	5	5
Additional paidin capital	691,194	675,346
Accumulated other comprehensive income (loss)	(1,468)	(413)
Accumulated deficit	(465,335)	(356,281)
Total stockholders' equity	224,396	318,657
Total liabilities and stockholders' equity	$ 270,052	$ 355,076