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.