Condensed Statements of Cash Flows (USD $)	3 Months Ended		86 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014
Operating activities
Net loss	$ (2,955,484)	$ (493,992)	$ (25,646,952)
Adjustments to reconcile net loss to net cash used in operating activities
Stock-based compensation expense	223,310	3,126	458,987
Non-cash interest	5,816	5,815	135,143
Change in fair value of purchase right liability			188,587
Change in fair value of warrant liability		124,000	54,264
Deferred rent expense	8,688		15,518
Changes in operating assets and liabilities:
Prepaid expenses	58,015	(10,500)	(176,247)
Other assets			(555,505)
Accounts payable and accrued expenses	659,038	(74,944)	1,501,352
Net cash used in operating activities	(2,000,617)	(446,495)	(24,024,853)
Financing activities
Proceeds from convertible promissory note			250,000
Proceeds from bank line of credit and loan advances		2,000,000	5,500,000
Payments on bank line of credit	(360,576)		(2,860,576)
Proceeds from issuance of common stock, net			25,125,528
Proceeds from issuance of preferred stock and purchase rights, net			17,744,041
Proceeds from exercise of stock options			101,358
Net cash provided by (used in) financing activities	(360,576)	2,000,000	45,860,351
Net increase (decrease) in cash and cash equivalents	(2,361,193)	1,553,505	21,835,498
Cash and cash equivalents at beginning of the period	24,196,691	116,013
Cash and cash equivalents at end of the period	21,835,498	1,669,518	21,835,498
Supplemental disclosures of cash flow information
Interest paid	32,495	25,750	261,246
Supplemental disclosures of non-cash financing information
Conversion of convertible promissory note and accrued interest to Series A Convertible Preferred Stock			292,538
Issuance of Series A Convertible Preferred Stock warrants		49,000	108,486
Conversion of Series A Convertible Preferred Stock to Common Stock at the initial public offering			$ 18,225,166