Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Payables And Accruals [Abstract]
Clinical research	$ 36	$ 552
Contract manufacturing services	821	1,444
Payroll and other employee-related expenses	1,336	1,648
Regulatory services	61	64
Consultant fees and expenses	76	70
Professional services fees	488	434
Interest expense	78	81
Other	156	74
Total accrued expenses and other current liabilities	$ 3,052	$ 4,367