Condensed Consolidated Balance Sheets (unaudited) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 346,068,406	$ 588,373,232
Marketable securities	305,203,086	100,157,618
Account receivable		1,000,000
Other receivables	5,175,378	7,443,654
Prepaid expenses and other current assets	8,209,888	6,113,122
Total current assets	664,656,758	703,087,626
Property, equipment and leasehold improvements, net	12,210,324	12,259,515
Operating lease right of use assets	4,876,584	1,992,669
Other assets	28,777	28,777
Total assets	681,772,443	717,368,587
Current liabilities:
Accounts payable	9,002,938	7,121,879
Accrued expenses	8,001,201	18,859,840
Deferred revenue	22,150,861	22,150,861
Current portion of operating lease liability	1,216,914	952,840
Total current liabilities	40,371,914	49,085,420
Deferred revenue	20,400,518	22,938,233
Long term debt	2,000,000	2,000,000
Operating lease liability	3,701,991	1,087,422
Total liabilities	66,474,423	75,111,075
Commitments and Contingencies
Stockholders’ equity:
Common stock, $0.001 par value; 48,785,692 and 48,455,741 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	48,786	48,455
Accumulated deficit	(532,853,201)	(491,888,910)
Additional paid-in capital	1,148,345,190	1,133,537,171
Accumulated other comprehensive income (loss)	(242,755)	560,796
Total stockholders’ equity	615,298,020	642,257,512
Total liabilities and stockholders’ equity	$ 681,772,443	$ 717,368,587