Condensed Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Consolidated net loss	$ (45,336,834)	$ (36,984,848)
Adjustments to reconcile consolidated net loss to net cash used in operating activities:
Gain on settlement of notes payable	0	(95,427)
Noncash stock compensation expense	12,840,048	16,066,856
Noncash stock expense associated with in-licensing agreements	0	5,350,094
Depreciation	10,326	2,454
Amortization of premium on investment securities	377,770	127,260
Change in fair value of notes payable	(93,522)	118,615
Changes in assets and liabilities:
Increase in restricted cash	(3,114)	0
Increase in other current assets	(4,055,116)	(7,585,956)
Increase in accrued interest receivable	(73,011)	(26,652)
Decrease in other assets	0	13,870
Increase in accounts payable and accrued expenses	4,658,128	3,269,629
Decrease in interest payable	0	(94,590)
Decrease in deferred revenue	(114,286)	(114,286)
Net cash used in operating activities	(31,789,611)	(19,952,981)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(59,194)	(4,498)
Investment in held-to-maturity securities	(40,955,137)	(9,218,008)
Proceeds from maturity of short-term securities	13,850,000	0
Net cash used in investing activities	(27,164,331)	(9,222,506)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from the exercise of warrants	1,009,985	2,890,305
Proceeds from the exercise of options	0	145,200
Payment of notes payable	0	(677,778)
Proceeds from sale of common stock, net	67,760,517	39,558,093
Financing costs	(68,404)	0
Net cash provided by financing activities	68,702,098	41,915,820
NET INCREASE IN CASH AND CASH EQUIVALENTS	9,748,156	12,740,333
Cash and cash equivalents at beginning of period	55,713,784	40,485,466
CASH AND CASH EQUIVALENTS AT END OF PERIOD	65,461,940	53,225,799
NONCASH TRANSACTIONS
Reclassification of deferred financing costs to additional paid-in capital	$ (63,788)	$ 0