The total duration of the study was 32 weeks and the study consisted of Periods A, B, and A+. Patients entered the study in Period A and were treated open-label with one of six commercially available antidepressant treatments (ADTs) for 8 weeks. Patients who met the blinded response criteria at the Week 6 Visit, were deemed early responders and were withdrawn from the study. At Week 8, patients with inadequate response to placebo + ADT, as per the randomisation criteria, entered Period B and were randomised to received double-blind brexpiprazole + ADT or placebo + ADT for 24 weeks. Non-randomised patients continued in Period A+ and received placebo + ADT until the end of the study. The primary objective was to compare the efficacy and safety of brexpiprazole with placebo. This comparison occurred Period B; therefore, the focus is Period B.
