Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Operating activities
Net loss	$ (8,192,745)	$ (8,842,852)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	32,466	9,799
Stock-based compensation	2,491,451	1,471,780
Restricted stock issued for services	64,000	1,958,450
Change in fair value of warrants	0	(19,807)
Debt discount amortization	223,352	0
Increase (decrease) in operating assets and liabilities:
Grant receivable	757,562	(52,272)
Other receivables	0	(106,010)
Prepaid expenses and other	56,318	213,426
Accounts payable	(877,179)	(331,501)
Accrued clinical operations and site costs	100,116	(134,569)
Accrued compensation	(80,227)	220,857
Other accrued expenses	199,752	307,090
Net cash used in operating activities	(5,225,134)	(5,305,609)
Investing activities
Purchases of property and equipment	(316,846)	(35,154)
Net cash used in investing activities	(316,846)	(35,154)
Financing activities
Cash received from bank loan, net of financing costs	4,610,324	0
Issuances of common stock, net of issuance costs	0	11,046,348
Proceeds from exercise of stock options	0	800
Principal payments on capital lease	(2,555)	0
Purchase of vested employee stock in connection with tax withholding obligation	(177,823)	0
Net cash provided by financing activities	4,429,946	11,047,148
Net change in cash and cash equivalents	(1,112,034)	5,706,385
Cash and cash equivalents at beginning of period	4,084,085	1,477,143
Cash and cash equivalents at end of period	2,972,051	7,183,528
Supplemental disclosure:
Cash paid during the period for income taxes	14,546	1,600
Supplemental disclosures of non-cash investing and financing information:
Capital lease in connection with purchases of equipment	95,656	0
Deemed dividend on beneficial conversion feature for preferred stock	0	17,852,921
Accretion of redemption value for Series A-1 and B preferred stock	0	93,234
Conversion of Series A-1 redeemable preferred stock into common stock	0	162,968
Conversion of Series C preferred stock to common stock	0	966
Conversion of Series B preferred stock to common stock	0	160,380
Exchange of Series A-1 preferred stock and warrants into common stock and Series D preferred stock	0	13,111,280
Conversion of Series D preferred stock to common stock	0	400
Exchange of Series B preferred stock and warrants into common stock and Series D preferred stock	0	10,451,783
Fair value of warrants issued	607,338	0
Warrants exercised to purchase common stock on a cashless basis	$ 0	$ 12,198