A Phase 1, Multicenter, Randomized, Double-blind, Sequential Cohort, Placebo-controlled Trial to Assess the Safety and Tolerability of Ascending Multiple Oral Doses of Brexpiprazole as Adjunctive Therapy in the Treatment of Elderly Subjects With Major Depressive Disorder

Incidence of Vital Signs of Potential Clinical Significance

Time Frame: Baseline, Titration Day 1, 2, 7, 8, Fixed Days 1, 2, 14, 15, 28, 29, Early Termination and Last Visit.

The vital signs were one of the primary parameters to measure the safety and tolerability of individual participants. Incidence of TEAEs of potential clinical relevance included abnormal values in heart rate, systolic and diastolic blood pressure, respiratory rate and weight that were identified based on pre-defined criteria.

Incidence of Physical Examination Evaluation of Potential Clinical Significance

Time Frame: Physical examination was performed at Screening, check-in, and discharge

The physical examination evaluation was one of the primary parameters to measure the safety and tolerability of individual participants. Incidence of TEAEs of potential clinical relevance include abnormal changes in the following body systems: head, ears, eyes, nose, and throat; thorax; abdomen; urogenital; extremities; neurological; and skin and mucosae.

Mean Change From Baseline to Study Completion in Simpson-Angus Scale (SAS) Total Score

Time Frame: End of Titration, Day 15, Day 29, Early Termination and Last visit

EPS was one of the primary parameters to measure the safety and tolerability of individual participants. The SAS is a rating scale used to measure EPS. The SAS scale consists of a list of 10 symptoms of parkinsonism (gait, arm dropping, shoulder shaking, elbow rigidity, wrist rigidity, head rotation, glabella tap, tremor, salivation, and akathisia), with each item rated from 0 to 4, with 0 being normal and 4 being the worst. The SAS Total score is sum of ratings for all 10 items, with possible Total scores from 0 to 40.

Incidence of ECG Evaluations of Potential Clinical Significance

Time Frame: Titratrion Day 1 and 7, Fixed dose Day 1, 14, 28, Early Termination

The measurement of ECG was one of the primary parameters to measure the safety and tolerability of individual participants. Incidence of TEAEs of potential clinical relevance include abnormal changes in heart rate and ECG intervals of PR, QRS, QT, QTcB, and QTcF that were identified based on pre-defined criteria.

Change From Baseline to Study Completion in C-SSRS Score.

Time Frame: Baseline, End of Titration, Fixed dose Day 14 and 28, Day 15 and 29, Early Termination, Last Visit

The C-SSRS was one of the primary parameters to measure the safety and tolerability of individual participants. Suicidality was monitored during the trial using the C-SSRS. This scale consists of a baseline evaluation that assesses the lifetime experience of the participant with suicide events and suicidal ideation and a post-baseline evaluation that focuses on suicidality since the last trial visit.

Number of Participants Who Tolerated Brexpiprazole

Time Frame: 45 Days

Safety and tolerability of brexpiprazole was noted to be primary outcome measure. Brexpiprazole was judged to be tolerated if at least 6 out of 8 (75%) of the participants in a test cohort tolerated the dose after 14 days of QD dosing at the end of the fixed dose phase based on the blinded data. Dose toleration was defined as follows: during the course of the trial, the participants did not experience any moderate or severe adverse events (AEs) or potentially clinically relevant changes from Baseline in laboratory values, vital signs, electrocardiogram (ECG) tracings, Columbia-Suicide Severity Rating Scale (C-SSRS), or extrapyramidal symptom (EPS) ratings, which were assessed as possibly related to the study drug, and would have warranted a dose decrease or discontinuation of the study drug. The safety and tolerability of brexpiprazole was defined by parameters: AEs, laboratory values, vital signs, ECG, C-SSRS, or EPS ratings, the results of each of the parameters reported separately.

Number of AEs Reported.

Time Frame: Throughout the study, up to 119 days

The AEs were one of the primary parameters to measure the safety and tolerability of individual participants. The AEs were captured for all participants from the time the ICF was signed until the end of the trial. AEs were measured throughout the 14-day titration and 28-day fixed dose phase until follow-up (30 \[±2\] days after last dose of study medication).

Incidence of Laboratory Values of Potential Clinical Significance

Time Frame: Titration Day 7, Fixed dose Day 14 and 28 and Last Visit

The laboratory values were one of the primary parameters to measure the safety and tolerability of individual participants. Incidence of TEAEs of potential clinical relevance include abnormal values in serum chemistry, hematology, urinalyses and prolactin tests that were identified based on pre-defined criteria.

Mean Change From Baseline to Study Completion in Barnes Akathisia Global Score

Time Frame: End of Titration, Day 15, Day 29, Early Termination and Last visit

EPS was one of the primary parameters to measure the safety and tolerability of individual participants. The Barnes Akathisia Rating Scale was an EPS rating scale. The Barnes Akathisia Rating Scale was used to assess the presence and severity of akathisia. This scale consists of 4 items. Only the 4th item, the Global Clinical Assessment of Akathisia, was evaluated in this trial. This item is rated on a 6 point scale, with 0 being best (absent) and 5 being worst (severe akathisia).

Mean Change From Baseline to Study Completion in Abnormal Involuntary Movement Scale (AIMS) Rating Score.

Time Frame: End of Titration, Day 15, Day 29, Early Termination and Last visit

EPS was one of the primary parameters to measure the safety and tolerability of individual participants. The AIMS Scale was an EPS rating scale. The AIMS is a 12 item scale. The first 10 items are rated from 0 to 4 (0=best, 4=worst). Items 11 and 12, related to dental status, have dichotomous responses, 0=no and 1=yes. The AIMS Total Score is the sum of the ratings for the first seven items. The possible total scores are from 0 to 28.