Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 81,499	$ 161,160
Marketable securities	51,010	138,343
Prepaid expenses	24,473	25,628
Receivables and other current assets	10,476	11,389
Total current assets	167,458	336,520
Marketable securities	40,641	97,114
Property, plant and equipment, net	14,566	9,706
Goodwill	5,646	5,646
Operating lease right-of-use assets	292,731	91,532
Restricted cash and other non-current assets	52,550	53,277
Total assets	573,592	593,795
Current liabilities:
Accounts payable	24,865	25,883
Accrued expenses and other current liabilities	75,550	103,958
Operating lease liability, current portion	48,446	23,152
Total current liabilities	148,861	152,993
Operating lease liability, net of current portion	244,522	66,432
Other non-current liabilities	93	93
Total liabilities	393,476	219,518
Commitments and contingencies (Note 9)
Stockholders’ equity:
Preferred stock, $0.01 par value, 5,000 shares authorized; 0 shares issued and outstanding at June 30, 2022 and December 31, 2021	0	0
Common stock, $0.01 par value, 125,000 shares authorized; 73,551 and 71,115 shares issued and outstanding at June 30, 2022 and December 31, 2021, respectively	735	711
Additional paid-in capital	4,126,012	4,096,402
Accumulated other comprehensive loss	(4,416)	(2,911)
Accumulated deficit	(3,942,215)	(3,719,925)
Total stockholders’ equity	180,116	374,277
Total liabilities and stockholders’ equity	$ 573,592	$ 593,795