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.