Condensed Consolidated Balance Sheets (Unaudited) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 219,260,000	$ 360,487,000
Short-term marketable securities	136,668,000	53,988,000
Prepaid expenses and other current assets	9,823,000	5,542,000
Total current assets	365,751,000	420,017,000
Long-term marketable securities	9,569,000	44,770,000
Property and equipment, net	24,875,000	15,954,000
Operating lease assets	41,051,000	17,356,000
Restricted cash	408,000	408,000
Other assets	4,775,000	2,910,000
Total assets	446,429,000	501,415,000
Current liabilities:
Accounts payable	4,319,000	4,677,000
Accrued expenses and other current liabilities	22,332,000	21,419,000
Operating lease liabilities	1,028,000	285,000
Total current liabilities	27,679,000	26,381,000
Operating lease liabilities, net of current portion	53,431,000	18,506,000
Total liabilities	81,110,000	44,887,000
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.0001 par value; 80,000,000 shares authorized as of September 30, 2022 and December 31, 2021; no shares issued and outstanding as of September 30, 2022 and December 31, 2021
Common stock, $0.0001 par value; 800,000,000 shares authorized as of September 30, 2022 and December 31, 2021; 122,306,969 and 121,382,547 shares issued at September 30, 2022 and December 31, 2021, respectively; 121,024,938 and 119,102,505 shares outstanding at September 30, 2022 and December 31, 2021, respectively	12,000	12,000
Additional paid-in capital	712,407,000	694,844,000
Accumulated other comprehensive loss	(1,379,000)	(162,000)
Accumulated deficit	(345,721,000)	(238,166,000)
Total stockholders' equity	365,319,000	456,528,000
Total liabilities and stockholders' equity	$ 446,429,000	$ 501,415,000