Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Payables And Accruals [Abstract]
Clinical expenses	$ 1,108	$ 1,793
Professional fees	675	573
Salaries and benefits	423	938
Manufacturing and distribution	198	173
Restructuring	196	357
Other	243	272
Accrued expenses	$ 2,843	$ 4,106