Safety and Tolerability of Oral OPC-34712 as Adjunctive Therapy in Adults With Major Depressive Disorder (the Orion Trial)

Inclusion Criteria:

- Male and Female outpatients 18-65 years of age

Eligible subjects from Trials 331-10-227, 331-10-228 or 331-12-282:

- Subjects who completed participation in the Double-blind Randomization Phase (i.e.
Week 14 visit) in Trial 331-10-227, Trial 331-10-228, or Trial 331-12-282 or

- Subjects who met criteria for a response, but did not meet criteria for remission at
Week 14 of either trial

Eligible subjects from other Phase 3, Double-blind, Brexpiprazole MDD trials:

• Subjects who completed the last scheduled visit of the prior Double-blind Randomized
Phase 3 trial.

Exclusion Criteria:

- Females who are breast-feeding and/or who have a positive pregnancy test result prior
to receiving OPC-34712.

- Subjects with a major protocol violation during the course of their participation in
the Double-blind Randomization Phase