Safety of switching to brexpiprazole in Japanese patients with schizophrenia: A post-hoc analysis of a long-term open-label study.

Objectives To determine the long-term safety of switching to brexpiprazole from aripiprazole or non-aripiprazole dopamine antagonists. Methods Post-hoc analysis of 56-week study of Japanese outpatients with schizophrenia switched to brexpiprazole 2 mg/day over 4-week switching period with further titration (1-4 mg/day) allowed during the 52-week, open-label period. Major assessment items: total/low-density lipoprotein (LDL)-/high-density lipoprotein (HDL)-cholesterol, triglycerides, blood glucose, body weight and prolactin. Secondary evaluations were related to efficacy, treatment emergent adverse events (TEAEs), extrapyramidal symptoms, and corrected QT interval (QTc). Results 84/186 (45.2%) patients (aripiprazole, 32.9%; non-aripiprazole, 54.8%) discontinued treatment over 56 weeks mainly because of consent withdrawal/adverse events. From baseline to Week 56, both groups showed minimal mean changes in total/LDL-/HDL-cholesterol, triglycerides, and glucose levels and a slight increase in mean (SD) body weight (aripiprazole, 1.1 [4.4] kg; non-aripiprazole, 0.4 [4.6] kg). Mean prolactin levels increased slightly in the aripiprazole group, but decreased in the non-aripiprazole group. Symptom severity scores decreased similarly in both groups. TEAEs occurred in 161/186 (86.6%) patients (aripiprazole, 84.1% [serious, 9.8%]; non-aripiprazole, 88.5% [serious, 14.4%]). Few changes occurred in extrapyramidal symptom scales or QTc interval. Conclusions Switching to brexpiprazole is associated with a low long-term risk for metabolic abnormalities (including weight gain), hyperprolactinemia, extrapyramidal symptoms and QTc changes and minimal changes in psychiatric symptoms.