Condensed Statements of Cash Flows (Unaudited) - USD ($)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash flows from operating activities
Net loss	$ (19,510,224)	$ (2,387,711)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation		1,821
Amortization of discount on marketable securities	81,504
Stock-based compensation	3,125,910
Interest accrued on convertible notes		397,064
Changes in operating assets and liabilities:
Prepaid expenses	(1,510,083)	(17,199)
Other assets	(21,190)
Accounts payable	2,321,726	282,838
Accrued expenses	2,927,521	(5,319)
Deferred revenue		1,500,000
Net cash used in operating activities	(12,584,836)	(228,506)
Cash flows from investing activities:
Purchases of marketable securities	(38,168,728)
Net cash used in investing activities	(38,168,728)
Cash flows from financing activities:
Proceeds from issuance of convertible notes payable		500,500
Proceeds from issuance of common stock, net of cost of issuance	49,816,044
Proceeds from the exercise of common stock options	89,486
Net cash provided by financing activities	86,568,613	477,349
Net increase in cash and cash equivalents	35,815,049	248,843
Cash and cash equivalents as of beginning of period	204,362	333,002
Cash and cash equivalents as of end of period	36,019,411	581,845
Supplemental schedule of non-cash financing activities
Conversion of convertible notes payable to preferred stock	200,000
Gain on extinguishment of preferred stock	(4,798,194)
Accretion of redeemable preferred stock	12,552,830
Conversion of preferred stock to common stock	94,896,589	1,060,194
Income taxes paid		247,500
Series C Redeemable Convertible Preferred Stock [Member]
Cash flows from financing activities:
Proceeds from issuance of Series C redeemable convertible preferred stock, net of costs of issuance	$ 36,663,083	$ (23,151)