Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Operating activities
Net loss	$ (2,447,320)	$ (972,898)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	4,323	1,790
Stock-based compensation	82,772	81,442
Change in fair value of warrants	(19,807)
Increase (decrease) in operating assets and liabilities:
Grants receivable	(155,195)
Other receivables	2,275
Prepaid expenses and other	44,474	(11,559)
Accounts payable	753,184	212,040
Accrued clinical operations and site costs	22,847	(302,773)
Accrued compensation	88,434	(80,123)
Other accrued expenses	200,483
Net cash used in operating activities	(1,423,530)	(1,072,081)
Investing activities
Purchases of property and equipment	(28,867)	(1,153)
Net cash used in investing activities	(28,867)	(1,153)
Financing activities
Issuances of preferred stock, net of issuance costs		2,973,655
Issuances of common stock, net of issuance costs	4,714,726
Net cash provided by financing activities	4,714,726	2,973,655
Net change in cash and cash equivalents	3,262,329	1,900,421
Cash and cash equivalents at beginning of year	1,477,143	354,254
Cash and cash equivalents at end of year	4,739,472	2,254,675
Supplemental disclosures of non-cash investing and financing information:
Deemed dividend on beneficial conversion feature for preferred stock	17,852,921	2,214,910
Accretion of redemption value for Series A-1 and B preferred stock	93,234	31,934
Issuance of common stock for accounts payable		240,000
Conversion of Series A-1 redeemable preferred stock into common stock	162,968
Conversion of Series C preferred stock to common stock	966
Conversion of Series B preferred stock to common stock	160,380
Exchange of Series A-1 preferred stock and warrants into common stock and Series D preferred stock	13,111,280
Exchange of Series B preferred stock and warrants into common stock and Series D preferred stock	$ 10,451,784