Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Accounts Payable And Accrued Liabilities Current [Abstract]
Accrued license fees	$ 791,820	$ 817,578
Accrued pre-commercial costs		341,159
Accrued consulting	205,290	102,156
Accrued contract research	137,318	99,140
Accrued miscellaneous expenses	51,394	73,348
Accrued contract manufacturing	91,363	218,108
Accrued audit and tax	142,715	111,250
Accrued legal	139,619	174,592
Accrued expenses	$ 1,559,519	$ 1,937,331