Treatment-emergent adverse events occurring during the Blinded Phase were defined as 1 or both of the following: 1) Any adverse events (AEs) with an onset date on or after the study drug start date and no later than 30 days after permanent discontinuation of study drug in the Blinded Phase (and before the first dosing date in the Open Label Extension (OLE) Phase), or 2) Any AEs leading to premature discontinuation of study drug in the Blinded Phase.

A serious adverse event was defined as an event that, at any dose, resulted in any of the following: death, life-threatening, in-patient hospitalization or prolongation of existing hospitalization, persistent or significant disability/incapacity, a congenital anomaly/birth defect, or a medically important event or reaction.

Treatment-emergent laboratory abnormalities occurring during the Blinded Phase were defined as values that increase at least 1 toxicity grade from baseline at any postbaseline time point, up to and including the date of last dose of study drug in the Blinded Phase plus 30 days (and prior to or on the first dose date of the OLE phase). The Common Terminology Criteria for Adverse Events (CTCAE) Version 4.03 was used for assigning toxicity grades (0 to 4, with higher grades indicating more severity).