An Assessment of the Impact of Prior Antipsychotic Treatment on the Duration of Treatment with RBP-7000 during a Long-Term Safety Study

Introduction: RBP-7000 (PERSERIS™) is a once-monthly subcutaneous extended-release risperidone formulation approved for the treatment of schizophrenia in adults, designed to deliver clinically relevant plasma concentrations on the first day of treatment (with no loading or supplemental dosing).

Methods: This 52-week open-label safety study (NCT02203838) treated men and women 18–65 years of age with stable schizophrenia for up to 12 months with RBP-7000 120 mg. This post hoc analysis evaluated the transition to RBP-7000 in 408 patients who were previously treated with a single antipsychotic agent.

Results: Previous treatments included oral risperidone (129 [32%]), aripiprazole (62 [15%]), quetiapine (58 [14%]), olanzapine (39 [10%]), and haloperidol (19 [5%]). Reasons for discontinuation were withdrawal of consent (83 [20%]), adverse events (46 [11%]) and lost to follow-up (39 [10%]). Compared with other antipsychotics, time to discontinuation, therefore treatment duration, was longer among patients who previously received risperidone prior to RBP-7000 (median/mean injections: 13/9, risperidone versus 9/8 other). More participants receiving prior antipsychotics other than risperidone discontinued RBP-7000 due to adverse events (31 [13%]) compared with risperidone (11 [9%]) and events related to treatment were 18 (8%) for the non-risperidone group and 6 (5%) for the risperidone group. Both groups remained symptomatically stable throughout the study.

Conclusion: Discontinuation rates in RBP-7000 patients were lower for those initially treated with risperidone compared to those treated with other antipsychotics. The reasons for these differences may, in part, be driven by the study design itself and improved tolerability in those who had been previously exposed to risperidone.