Pimavanserin (Pim) is a 5HT2A inverse agonist that is the only Food and Drug Administration–approved treatment for Parkinson disease (PD) psychosis. The published open-label experience is limited.
This report is a chart review of all patients who were started on the drugs since the one earlier report on 15 patients. All patients were included, whether or not they completed 6 weeks of treatment, the time required for maximum benefit found in the published phase 3 trial.
Twenty-six patients are reported. Three patients had dementia with Lewy bodies; one had an atypical parkinsonism; 22 had PD, including one with schizophrenia and neuroleptic exacerbated, dopamine transporter scan–positive idiopathic PD; and another had PD complicated by strokes. Six stopped before 6 weeks due to adverse effects, including 1 with worsened psychosis. Eighteen completed at least 6 weeks of treatment. Of these, 3 stopped due to lack of efficacy and 3 due to worsened psychosis. Twelve found it helpful. Of the 18 who took Pim for at least 6 weeks, 12 improved and continue to take it.
Almost 50% of parkinsonian patients with psychotic symptoms found Pim to be a useful medication, which they continue to take. Reasons for intolerance varied and were thought to be unrelated to the drug.
Department of Neurology, Butler Hospital; and Department of Neurology, Warren Alpert Medical School of Brown University, Providence, RI.
Address correspondence and reprint requests to Joseph H. Friedman, MD, Department of Neurology, Butler Hospital, 345 Blackstone Blvd, Providence, RI 02906; E-mail: Joseph_Friedman@brown.edu
Conflicts of Interest and Source of Funding: This study is supported by a research funding from the National Institutes of Health and Michael J. Fox Foundation for Parkinson's Research. The author is a consultant at Acadia Pharmaceuticals.