CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 93,510	$ 109,966
Marketable securities (Note 4)	427,034	264,915
Accounts receivable	0	15,000
Contract assets	2,030	3,762
Prepaid expenses and other current assets	14,679	11,674
Total current assets	537,253	405,317
Marketable securities, non-current (Note 4)	224,390	61,434
Property and equipment, net (Note 6)	49,336	48,134
Right-of-use assets, operating leases	49,329	52,945
Other non-current assets	2,118	2,118
Restricted cash	5,825	5,811
Total assets	868,251	575,759
Current liabilities:
Accounts payable	6,812	7,075
Accrued expenses (Note 8)	15,997	33,864
Deferred revenue	22,613	37,883
Operating lease liabilities	8,757	5,068
Finance lease liabilities	1,133	1,277
Other current liabilities	824	524
Total current liabilities	56,136	85,691
Non-current liabilities
Deferred revenue, net of current portion	23,781	16,768
Operating lease liabilities, net of current portion	75,975	77,028
Finance lease liabilities, net of current portion	1,156	1,301
Total liabilities	157,048	180,788
Stockholders’ equity:
Common stock, $0.0001 par value; 150,000,000 shares authorized at March 31, 2024 and December 31, 2023, 61,353,146 and 55,585,305 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively	6	6
Additional paid-in capital	1,292,283	926,269
Accumulated deficit	(579,309)	(530,752)
Accumulated other comprehensive loss	(1,777)	(552)
Total stockholders’ equity	711,203	394,971
Total liabilities and stockholders’ equity	$ 868,251	$ 575,759