Treatment Discontinuation Among Patients with Schizophrenia Treated with Brexpiprazole and Other Oral Atypical Antipsychotics in Japan: A Retrospective Observational Study

Abstract

Introduction: Treatment continuation is essential for relapse prevention in patients with schizophrenia. The aim of this exploratory study was to compare the time to treatment discontinuation between patients with schizophrenia prescribed brexpiprazole (BRX group) and those prescribed other atypical antipsychotics (OAA group) in clinical settings in Japan using health insurance claims data.

Methods: De-identified data of working individuals with schizophrenia aged < 75 years and their dependents were assessed from April 2017 to May 2020 using a nationwide claims database. Cox proportional hazards models, adjusted for baseline patient variables, were used to compare the time to treatment discontinuation (primary outcome) for 180 days between BRX and OAA groups and to estimate the hazard ratio (HR) with 95% confidence interval (CI). The cumulative treatment continuation rates at 180 days were also estimated. Sensitivity and subgroup analyses were conducted for the primary outcome.

Results: The analysis included 978 and 4898 patients in the BRX and OAA groups, respectively. Patients in the BRX group were significantly less likely to discontinue treatment than those in the OAA group (HR 0.86, 95% CI 0.78-0.95; p = 0.0024). The cumulative treatment continuation rates were higher in the BRX group (45.9%, 95% CI 42.5-49.2]) than in the OAA group (39.5%, 95% CI 38.1-41.0; log-rank test, p < 0.0001). Based on patients matched by propensity score, the BRX group was significantly less likely to discontinue treatment than the OAA group (log-rank test, p = 0.0466). Similar results were obtained in sensitivity and subgroup analyses.

Conclusion: This real-world study showed that patients in the BRX group were less likely to discontinue treatments than those in the OAA group. These findings suggest that BRX may contribute to treatment continuation among patients with schizophrenia.

Trial registration: University hospital Medical Information Network (UMIN) Clinical Trials Registry: UMIN000044682.

Keywords: Atypical antipsychotics; Brexpiprazole; Japan; Real-world; Schizophrenia; Treatment continuation.