Brexpiprazole as an augmentation agent to antidepressants in treatment resistant major depressive disorder.

Introduction: Approximately 50% of adults with major depressive disorder (MDD) who receive a first-line antidepressant treatment, at an appropriate dose, do not achieve an adequate response. Brexpiprazole is a novel serotonin-dopamine activity modulator in the second generation/atypical antipsychotic class that was approved by the United States Food & Drug Administration in 2015 for use as an adjunctive agent in the treatment of MDD inadequately responsive to antidepressant treatment. In general, second generation/atypical antipsychotics are widely used in the treatment of treatment resistant depression with brexpiprazole providing preliminary evidence for broad-spectrum efficacy across multiple domains affected by MDD, providing a basis for further elucidating its mechanistic effects to inform novel drug discovery. Areas covered: The review herein presents the evidence base for the use of brexpiprazole as an augmentation agent to antidepressants in individuals with treatment resistant MDD, including its efficacy, safety, and tolerability profile. Expert opinion: Brexpiprazole has been demonstrated to be effective and safe to use as an augmentation agent to antidepressant treatment among individuals with treatment resistant MDD due to its considerably improved tolerability profile when compared to other second generation/atypical antipsychotics; however, it is important to exercise clinical judgment when selecting disparate augmentation agents on a case-by-case basis weighing individual risks versus benefits.