A multicenter, single-arm, open-label interventional study of adherence to brexpiprazole during switching from previous antipsychotic drugs in patients with schizophrenia or schizoaffective disorder.

The rate of medication persistence was examined in patients with schizophrenia or schizoaffective disorder during switching from previously administered antipsychotics to brexpiprazole, a new dopamine D₂ receptor partial agonist. A multicenter, single-arm, open-label 24-week interventional study was conducted, consisting of two 12-week consecutive periods: an initial switch (by plateau cross-titration) with the subsequent period, followed by a second maintenance period. Prior antipsychotics were olanzapine or risperidone/paliperidone. The primary and secondary outcome measures were medication persistence rates after the first 12 weeks and changes from baseline in the Specific Levels of Functioning Scale (SLOF), Subjective Well-being under Neuroleptic drug treatment Short form (SWNS), and Positive and Negative Syndrome Scale (PANSS) scores, respectively. In total, 79 patients were administered brexpiprazole and the medication persistence rate at 12 weeks was 78.5%, which was significantly higher than the predefined threshold of 65%. Regarding the prior medication, the persistence rate at 12 weeks was 84.6% for olanzapine and 72.5% for risperidone/paliperidone. Significant improvements from baseline were observed in the SLOF, SWNS, and PANSS scores. There were no adverse events of concern. Thus, brexpiprazole appeared to be a suitable antipsychotic on switching from olanzapine, risperidone, or paliperidone.