Evaluation of Mortality in Users of Pimavanserin Compared with Other Atypical Antipsychotics in Patients with Parkinson’s Disease Psychosis: An Update

Introduction Pimavanserin is the only antipsychotic medication approved in the USA to specifically treat hallucinations and delusions associated with Parkinson’s disease psychosis (PDP). Objective To compare mortality risk in patients with PDP after initiation of pimavanserin or comparator atypical antipsychotics in an overall PDP cohort and in a subcohort of patients residing in long-term care or skilled nursing facilities (LTC/SNFs). Methods This cohort study identified patients aged ≥ 65 years with PDP initiating pimavanserin or a comparator antipsychotic in US Medicare claims (2016–2021). Cox proportional hazards models were used to estimate hazard ratios (HRs) comparing all-cause mortality in the propensity score-matched treatment groups. Cumulative incidence curves, time period-specific relative risk, and risk difference estimates evaluated risk over time. Results In this follow-up analysis, we identified 4384 pimavanserin initiators and 28,042 comparator initiators in the overall PDP cohort, and 921 pimavanserin initiators and 7963 comparator initiators in the LTC/SNF subcohort. After matching, the overall PDP cohort had 4381 patients in each treatment group, and the LTC/SNF subcohort had 905 patients in each group. The matched HR for mortality (pimavanserin versus comparator) was 0.76 (95% CI 0.68–0.85) in the overall PDP cohort and 0.90 (95% CI 0.74–1.10) in the LTC/SNF subcohort. In the overall PDP cohort, time period-specific relative risks and risk differences showed that pimavanserin initiators had a lower risk of mortality throughout the first 365 days of follow-up. Conclusion In the overall PDP cohort, mortality risk was lower among pimavanserin initiators than comparator antipsychotic initiators.