Condensed Consolidated Statements of Cash Flows - USD ($)	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (29,747,724)	$ (31,680,918)
Adjustments to reconcile net loss to net cash used in operating activities:
Noncash stock compensation expense	3,347,362	11,600,014
Depreciation	23,319	5,805
Amortization of premium on investment securities	254,132	205,409
Change in fair value of notes payable	(90,384)	20,170
Changes in assets and liabilities:
Increase in restricted cash	(2,018)	(2,098)
Increase in other current assets	(5,700,293)	(5,117,040)
Increase in leasehold interest	(1,968,734)	0
Decrease (increase) in accrued interest receivable	52,255	(104,797)
Increase in other assets	(9,518)	0
Increase in accounts payable and accrued expenses	3,712,012	4,018,767
Increase in deferred rent	681,720	0
Decrease in deferred revenue	(76,191)	(76,191)
Net cash used in operating activities	(29,524,062)	(21,130,879)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(310,056)	(20,280)
Investment in held-to-maturity securities	(15,199,922)	(35,070,625)
Proceeds from maturity of short-term securities	15,000,000	7,850,000
Net cash used in investing activities	(509,978)	(27,240,905)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from the exercise of warrants	50,271	992,644
Proceeds from sale of common stock, net	3,504,261	51,984,879
Financing costs	(3,989)	(19,437)
Net cash provided by financing activities	3,550,543	52,958,086
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(26,483,497)	4,586,302
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	55,061,329	55,713,784
CASH AND CASH EQUIVALENTS AT END OF PERIOD	28,577,832	60,300,086
NONCASH TRANSACTIONS
Accrued financing costs	0	47,797
Reclassification of deferred financing costs to additional paid-in capital	(56,988)	(48,771)
Conversion of convertible notes payable to common stock	$ 30,601	$ 0