Objective: To analyze the effect of brexpiprazole on metabolic parameters and body weight in adults with schizophrenia, including clinically relevant sub-groups of patients, based on data from two pivotal phase 3 studies (NCT01393613; NCT01396421) and a long-term extension study (NCT01397786).
Methods: The short-term studies were randomized, double-blind, placebo-controlled, fixed-dose (2 and 4 mg/day), 6-week phase 3 studies. The long-term study was an open-label 52-week study, recruiting de novo patients and those completing either short-term study. Maximum exposure to brexpiprazole was 58 weeks. Fasting metabolic parameters and weight were measured throughout the studies. Metabolic values were characterized as normal, borderline, or high (cholesterol, triglycerides, and glucose) and low or normal (HDL), using commonly reported thresholds. The incidences of all possible shifts in metabolic parameters were measured from baseline to any time post-baseline during the first 6 weeks, first 6 months, and last 6 months of treatment.
Results: In short-term studies, the proportion of brexpiprazole-treated patients with unfavorable shifts in metabolic parameters was low and like that of placebo-treated patients; the incidence of these shifts was not dose-dependent. During both short- and long-term treatment, the incidence of unfavorable shifts with brexpiprazole was lower than that of favorable shifts. During short-term studies, the mean increase in body weight was 1.2 kg with brexpiprazole treatment and 0.2 kg with placebo. The mean increase in body weight during long-term treatment was 3.2 kg at week 58.
Conclusions: Brexpiprazole treatment was associated with moderate weight gain and small changes in metabolic parameters during both short- and long-term treatment.
Keywords: Brexpiprazole; metabolic parameters; schizophrenia; weight gain.