Adjunctive brexpiprazole for elderly patients with major depressive disorder: An open-label, long-term safety and tolerability study

Objectives The objective of this study was to evaluate the long-term safety and tolerability of flexible-dose brexpiprazole adjunct to antidepressant treatment (ADT) in elderly patients with major depressive disorder (MDD). Methods Elderly patients (≥65 years) with MDD and inadequate response to ≥1 ADT during the current episode were recruited to a 26-week, interventional, open-label study (NCT02400346) at outpatient centers in the USA and Europe. All patients received brexpiprazole 1 to 3 mg/day adjunct to their current ADT. Safety outcomes included adverse events (AEs), movement disorder scales, and standard safety assessments (vital signs, laboratory safety parameters, physical examination, electrocardiograms). Exploratory efficacy outcomes included the Montgomery-Asberg Depression Rating Scale (MADRS), Clinical Global Impressions-Severity of Illness (CGI-S), and Social Adaptation Self-Evaluation Scale (SASS). Results Of the 132 treated patients, 88 (66.7%) completed the study and 44 (33.3%) withdrew, including 24 who withdrew because of AEs (18.2%). Overall, 102 patients (77.3%) experienced ≥1 treatment-emergent AE (TEAE), which were mostly mild or moderate in severity. Treatment-emergent AEs with the highest incidence were fatigue (15.2%) and restlessness (12.9%). The most common TEAE leading to withdrawal was fatigue (3.0%). No consistent clinically relevant findings were seen with regard to movement disorder scales or standard safety assessments. Mean (standard error) efficacy score changes from baseline to week 26 were: MADRS total, -14.5 (0.9); CGI-S, -1.8 (0.1); and SASS, 3.2 (0.5). Conclusions Long-term (26-week) treatment with adjunctive brexpiprazole was generally well tolerated in elderly patients with MDD and inadequate response to prior ADT. Improvements were observed in depressive symptoms and social functioning.