A Multicenter, Open-Label Study to Evaluate the Long-term Safety and Efficacy of Adjunctive Brexpiprazole 2 mg Daily in Japanese Patients with Major Depressive Disorder.

BACKGROUND AND

objectiveInadequate response to antidepressant monotherapy is common among patients with major depressive disorder (MDD). The efficacy and safety of adjunctive brexpiprazole 2 mg/day has recently been confirmed during the 6-week, randomized, placebo-controlled phase 2/3 (BLESS) study, which evaluated brexpiprazole at 1 mg/day and 2 mg/day versus placebo as adjunctive therapy to antidepressant therapies in 740 Japanese patients with MDD and an inadequate response to antidepressant monotherapy. This study evaluated the long-term safety and efficacy of adjunctive fixed-dose brexpiprazole 2 mg/day in Japanese patients with MDD.

methodsAn open-label, 52-week study enrolled rollover patients who completed the 6-week, double-blind, randomized, placebo-controlled phase 2/3 BLESS study (NCT03697603), and de novo patients aged ≥ 65 years. Patients were titrated to fixed-dose brexpiprazole 2 mg/day from Week 1. Safety assessments included treatment-emergent adverse events (TEAEs; primary outcome) and clinical and laboratory variables. Efficacy was assessed using the Montgomery-Åsberg Depression Rating Scale (MADRS), Clinical Global Impression-Improvement (CGI-I) scale, Hamilton Depression Rating Scale (HAM-D) 17-item total score, and Sheehan Disability Scale (SDS) score.

resultsIn total, 247 patients [rollover, n = 216; de novo (previously unexposed), n = 31] were included in the safety/efficacy populations, and 138 (rollover, n = 132; de novo, n = 6; 55.9%) completed the study. Common TEAEs (incidence ≥ 10%) were weight gain [33.2% (n = 82)], akathisia [23.5% (n = 58)], nasopharyngitis [21.1% (n = 52)], and somnolence [10.5% (n = 26)]. TEAEs leading to treatment discontinuation occurred in 26.7% of patients receiving brexpiprazole and 58.1% of de novo patients. The mean (SD) increase in body weight from baseline to Week 52 [observed cases (OC)] was 4.2 (6.5) kg (n = 138); 44.5% (n = 110) had weight gain ≥ 7% at any postbaseline visit. There were no cases of tardive dyskinesia and no AEs related to suicide/suicide attempts. One death occurred (unknown cause), which was unrelated to study treatment. Improvements in the MADRS total score were observed from baseline over the course of the 52-week study [mean (SD) change at Week 52 (OC): - 7.3 (8.7)] for all patients receiving brexpiprazole. The overall MADRS response rate and remission rate in patients receiving brexpiprazole was 41.3% (n = 57) and 34.8% (n = 48), respectively, at Week 52 (OC). Improvements in CGI-S, HAM-D 17 item total score, and SDS mean scores were also observed from baseline over the 52-week study, with a mean (SD) change from baseline at Week 52 (OC) of - 0.8 (1.0), - 5.9 (6.3), and - 1.0 (2.2), respectively, indicating a sustained improvement in symptoms with long-term brexpiprazole treatment.

conclusionsThis is the first study to evaluate the safety profile of brexpiprazole 2 mg/day in Japanese patients with MDD, including older adults, which is similar to previous reports, with no new safety risks, and continued efficacy over 52 weeks. STUDY REGISTRATION: ClinicalTrials.gov (NCT03737474; registered on 29 July 2018).