Real-world Persistency Outcomes associated with Pimavanserin vs other-AAPs for Parkinson’s Disease Psychosis: Analysis of Medicare Beneficiaries from 100% Sample

Abstract: OBJECTIVES: Treatment persistence (i.e., measure of real-world treatment utilization relative to patient preference) with pimavanserin (PIM), the only FDA approved atypical antipsychotic (AAP) for hallucinations and delusions associated with Parkinson’s Disease Psychosis (PDP) vs. other-AAPs (quetiapine, risperidone, olanzapine, and aripiprazole) is needed. METHODS: Claims data of PDP patients newly initiating PIM or other-AAP monotherapy (i.e., index date) during 01/01/14-12/31/18 with a 6-month pre-/post-index follow-up from 100% Medicare sample was analyzed. Eligible patients were propensity score matched 1:1 based on 31 variables (age, sex, region, race, and 27 elixhauser comorbidities). Six-month post-index treatment persistence was defined as: (i) discontinuation rates with ≥ 45-day treatment-gap, and (ii) proportion of days covered (i.e., number of prescription-days/180). Differences in PIM vs other-AAPs were described using chi-square and t-tests and compared using generalized linear models (GLM) which controlled for demographic characteristics, comorbidities, coexisting dementia, and coexisting insomnia. RESULTS: Of 10,563 eligible PDP patients, 9.25% (n=977) and 90.75% (n=9586) patients-newly initiated PIM and other-AAPs, respectively. Among other-AAPs, 72.68% (n=7677), 9.70% (n=1024),4.8% (n=507) and 3.58% (n=378) were on quetiapine, risperidone, olanzapine, and aripiprazole. Mean age was 77.98 (±7.83) years and 47.80% (n=5,050) were female. Among 1:1 matched PIM (n=977) vs. other-AAP (n=977) patients, 7.2% (n=70) vs. 10.2% (n=100) patients on PIM vs. other-AAPs discontinued monotherapy (p