Pimavanserin treatment of hallucinations and delusions in patients with Parkinson’s disease dementia: post hoc analysis of the HARMONY trial

Abstract: Introduction: Pimavanserin 34 mg is approved in the US to treat hallucinations and delusions associated with Parkinson’s Disease psychosis (PDP). The efficacy and safety of pimavanserin for the treatment of dementia-related psychosis (DRP), including PDD patients, was evaluated in the HARMONY phase 3, randomized, placebo-controlled discontinuation study. Methods: Eligible patients received pimavanserin for 12 weeks during the open-label (OL) period (Nf392). Patients with sustained response at weeks 8 and 12 were randomized 1:1 to continue pimavanserin or receive placebo for up to 26 weeks in the double-blind (DB) period. The primary endpoint was time from randomization to psychosis relapse. The Extrapyramidal Symptom Rating Scale-Abbreviated (ESRS-A) and Mini-Mental State Examination (MMSE) were used to evaluate motor function and cognition. Results: 59 enrollees had PDD and initiated pimavanserin 34 mg, 49/59 continued to receive pimavanserin 34 mg. In the OL period, most PDD patients (73.5% [36/49]) exhibited a sustained response and were randomized to pimavanserin (n=16) or placebo (n=20). The risk of psychosis relapse was lower with pimavanserin than placebo (HR: 0.052; 95% CI: 0.016, 0.166; 1-sided P