Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Accounts Payable And Accrued Liabilities Current [Abstract]
Accrued legal	$ 129,783	$ 174,592
Accrued pre-commercial costs	331,892	341,159
Accrued consulting	186,905	102,156
Accrued audit and tax	48,745	111,250
Accrued license fees	840,791	817,578
Accrued contract manufacturing	342,437	218,108
Accrued contract research	188,723	99,140
Accrued miscellaneous expenses	83,210	73,348
Accrued expenses	$ 2,152,486	$ 1,937,331