A Study of Flexible-dose Brexpiprazole as Adjunctive Therapy in the Treatment of Adults With Major Depressive Disorder, the Delphinus Trial

This is a trial designed to assess the safety and efficacy of brexpiprazole (flexible dose)
as adjunctive therapy to an assigned known anti-depressant in depressed subjects. The trial
consists of a continuous 18-week double-blind treatment period with a 30-day follow-up.
Subjects who complete all trial visits through the Week 18 visit may be offered entry into an
optional open-label rollover trial.

Inclusion Criteria:

- Male and female outpatients 18 to 65 years of age, inclusive, at the time of informed
consent.

- Subjects with both a diagnosis of MDD, and in a current major depressive episode, as
defined by DSM-IV-TR criteria

- Subjects willing to discontinue all prohibited psychotropic medications to meet
protocol-required washouts prior to and during the trial period.

Exclusion Criteria:

- Females who are breast-feeding and/or who have a positive pregnancy test result during
screening prior to receiving trial medication

- Subject has a current Axis I (DSM-IV-TR) diagnosis of: dementia, Schizophrenia,
Bipolar, Eating disorder , Obsessive-compulsive disorder, Panic disorder,
Posttraumatic stress disorder

- Subjects experiencing hallucinations, delusions or any psychotic symptomatology in the
current major depressive episode.

- Subjects who have met DSM-IV-TR criteria for substance abuse or dependence within the
past 180 days

- Subjects currently treated with insulin for diabetes.

- Subjects with uncontrolled hypertension

- Subjects with known ischemic heart disease or history of myocardial infarction,
congestive heart failure, angioplasty, stenting, or coronary artery bypass Surgery

- Subjects with a positive drug screen for cocaine, marijuana, or other illicit drugs

- Inability to swallow tablets or tolerate oral medication

- Abnormal laboratory test results, vital signs and ECG results

- Subjects who previously participated in any prior brexpiprazole clinical trial.