Aims: Inadequate antidepressant response interrupts effective treatment of major depressive disorder (MDD). The BLESS study evaluates the dosage, efficacy, and safety of brexpiprazole adjunctive therapy in Japanese patients with inadequate antidepressant therapy (ADT) response.
Methods: This placebo-controlled, randomized, multicenter, parallel-group phase 2/3 study randomized Japanese MDD patients (Hamilton Rating Scale for Depression 17-item total score ≥ 14; historical inadequate response to 1-3 ADTs) with inadequate response to 8-week single-blind, prospective SSRI/SNRI treatment to 6-week adjunctive treatment with brexpiprazole 1 mg, 2 mg, or placebo. The primary endpoint was change in Montgomery-Åsberg Depression Rating Scale (MADRS) total score from baseline. Secondary endpoints included MADRS response, remission rate, and Clinical Global Impression-Improvement score. Safety was comprehensively evaluated, especially regarding antipsychotic adverse events (AEs).
Results: Of 1194 screened patients, 740 were randomized and 736 (1 mg, n = 248; 2 mg, n = 245; placebo, n = 243) had ≥1 baseline/post-baseline MADRS total score. The LSM (SE) change from baseline in MADRS total score at Week 6 by MMRM analysis was -8.5 (0.47) with brexpiprazole 1 mg, -8.2 (0.47) with brexpiprazole 2 mg, and -6.7 (0.47) with placebo (placebo-adjusted LSM difference [95% CI]: 1 mg, -1.7 [-3.0, -0.4]; P = 0.0089; 2 mg, -1.4 [-2.7, -0.1]; P = 0.0312). Secondary efficacy results supported the primary endpoint. Brexpiprazole was generally well tolerated.
Conclusion: Brexpiprazole 1 mg daily was an appropriate starting dose and both 1 mg and 2 mg daily were effective and well tolerated as adjunctive therapy for Japanese MDD patients not adequately responsive to ADT.
Keywords: Japanese; adjunctive therapy; antipsychotic; brexpiprazole; major depressive disorder.
© 2023 The Authors. Psychiatry and Clinical Neurosciences published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Psychiatry and Neurology.