A Randomized, Placebo-Controlled Study of the Efficacy and Safety of Fixed-Dose Brexpiprazole 2 mg/d as Adjunctive Treatment of Adults With Major Depressive Disorder.

OBJECTIVE: To assess the efficacy, safety, and tolerability of brexpiprazole as adjunct to antidepressant treatment (ADT) in adults with major depressive disorder (MDD) and inadequate response to ADTs. METHODS: Outpatients with inadequate response to 1-3 ADTs during their current depressive episode (DSM-IV-TR criteria) were administered prospective, open-label ADT. Those patients with inadequate response to prospective ADT were randomized to double-blind, adjunctive brexpiprazole 2 mg/d or placebo. The primary efficacy end point was the change from baseline (randomization) to week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Key secondary efficacy end points were the change in Sheehan Disability Scale (SDS) mean score for all patients and the change in MADRS total score for subgroups with minimal response to prospective ADT and DSM-5-defined anxious distress. The study was conducted from July 2014 to May 2016. RESULTS: Adjunctive brexpiprazole (n = 191) improved MADRS total score from baseline to week 6 versus placebo (n = 202; least squares mean difference [95% confidence limits]: -2.30 [-3.97, -0.62]; P = .0074). There was no separation between groups for the SDS mean score (-0.22 [-0.66, 0.23]; P = .33). Adjunctive brexpiprazole also improved MADRS total score versus placebo in the subgroups with minimal response to prospective ADT (-2.25 [-4.23, -0.27]; P = .026) and anxious distress (-2.98 [-5.24, -0.72]; P = .0099). Treatment with adjunctive brexpiprazole was well tolerated with no unexpected side effects. CONCLUSIONS: This study adds to the substantial body of evidence for the efficacy and tolerability of brexpiprazole as adjunctive treatment in patients with MDD and inadequate response to ADTs. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02196506; EudraCT number: 2014-000062-22​​​.

Efficacy and safety of flexibly dosed brexpiprazole for the adjunctive treatment of major depressive disorder: a randomized, active-referenced, placebo-controlled study.

OBJECTIVE: To assess the efficacy, safety, and tolerability of brexpiprazole as adjunctive treatment in adults with major depressive disorder (MDD) and an inadequate response to prior antidepressant treatment (ADT). METHODS: Patients with a current major depressive episode after prior treatment with 1-3 ADTs entered an 8- or 10-week prospective treatment phase in which they received double-blind placebo adjunct to open-label ADT. Inadequate responders were randomized (2:2:1) to brexpiprazole 2-3 mg/day, placebo, or quetiapine extended-release (XR) 150-300 mg/day, adjunct to the same ADT, for 6 weeks. The primary efficacy endpoint was the change from baseline (randomization) to week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) total score. The key secondary efficacy endpoint was the change in Sheehan Disability Scale (SDS) mean score. RESULTS: Adjunctive brexpiprazole showed a greater improvement in MADRS total score than adjunctive placebo (least squares mean difference [95% confidence interval] = -1.48 [-2.56, -0.39]; p = .0078), whereas adjunctive quetiapine XR did not separate from placebo (-0.30 [-1.63, 1.04]; p = .66). Adjunctive brexpiprazole failed to separate from placebo on the SDS mean score (-0.23 [-0.52, 0.07]; p = .13), but did improve functioning on two of the three SDS items (family life and social life). The most frequent treatment-emergent adverse events in patients receiving brexpiprazole were akathisia (6.1%), somnolence (5.6%), and headache (5.6%). CONCLUSIONS: Adjunctive brexpiprazole 2-3 mg/day improved symptoms of depression compared with adjunctive placebo in patients with MDD and an inadequate response to ADTs, and was well tolerated with no unexpected side effects.

A case study in identifying targeted patients population in major depressive disorder by enhanced enrichment design.

Despite advances in clinical trial design, failure rates near 80% in phase 2 and 50% in phase 3 have recently been reported. The challenges to successful drug development are particularly acute in central nervous system trials such as for pain, schizophrenia, mania, and depression because high-placebo response rates lessen assay sensitivity, diminish estimated treatment effect sizes, and thereby decrease statistical power. This paper addresses the importance of rigorous patient selection in major depressive disorder trials through an enhanced enrichment paradigm. This approach led to a redefinition of an ongoing, blinded phase 3 trial algorithm for patient inclusion (1) to eliminate further randomization of transient placebo responders and (2) to exclude previously randomized transient responders from the primary analysis of the double blind phase of the trial. It is illustrated for a case study for the comparison between brexpiprazole + antidepressant therapy and placebo + antidepressant therapy. Analysis of the primary endpoint showed that efficacy of brexpiprazole versus placebo could not be established statistically if the original algorithm for identification of placebo responders was used, but the enhanced enrichment approach did statistically demonstrate efficacy. Additionally, the enhanced enrichment approach identified a target population with a clinically meaningful treatment effect. Through its successful identification of a target population, the innovative enhanced enrichment approach enabled the demonstration of a positive treatment effect in a very challenging area of depression research.

Efficacy and safety of adjunctive brexpiprazole 2 mg in major depressive disorder: a phase 3, randomized, placebo-controlled study in patients with inadequate response to antidepressants.

OBJECTIVE: To assess the efficacy, tolerability, and safety of brexpiprazole as adjunctive therapy to antidepressant treatments (ADTs) in adults with major depressive disorder (as defined by DSM-IV-TR criteria) and inadequate response to ADTs. METHOD: Patients with historical inadequate response to 1-3 ADTs were enrolled. All patients entered a prospective 8-week phase on physician-determined, open-label ADT. Those with inadequate response were randomized to ADT + brexpiprazole 2 mg/d or ADT + placebo for 6 weeks. The study was conducted between July 2011 and May 2013. The primary efficacy end point was change from baseline to week 6 in Montgomery-Asberg Depression Rating Scale (MADRS) total score. The key secondary end point was change from baseline to week 6 in Sheehan Disability Scale (SDS) mean score. The efficacy population comprised all patients who had ≥ 1 dose of study drug in the double-blind phase and both baseline and ≥ 1 postrandomization MADRS scores. The efficacy population per final protocol included patients from the efficacy population who met amended randomization criteria of inadequate response throughout prospective treatment. RESULTS: Brexpiprazole (n = 175) reduced mean MADRS total score versus placebo (n = 178) at week 6 in the efficacy population per final protocol (-8.36 vs -5.15, P = .0002). Brexpiprazole improved SDS mean score versus placebo (-1.35 vs -0.89, P = .0349). The most common treatment-related adverse events were weight gain (brexpiprazole, 8.0%; placebo, 3.1%) and akathisia (7.4% vs 1.0%). CONCLUSIONS: Adjunctive brexpiprazole therapy demonstrated efficacy and was well tolerated in patients with major depressive disorder and inadequate response to ADTs. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01360645.