Accounts Payable and Accrued Expenses (Details) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Accrued Liabilities
Accrued research and development costs	$ 2,896,668	$ 972,218
Accrued compensation	424,533	100,000
Accrued professional fees	548,258	4,024,234
Other liabilities	303,264	404,283
Total	$ 4,172,723	$ 5,500,735