(HealthDay News) — For patients with dementia-related psychosis who have a response to pimavanserin, the risk for relapse is lower with continuation of the drug versus discontinuation, according to a study published in the July 22 issue of the New England Journal of Medicine.
Pierre N. Tariot, M.D., from the Banner Alzheimer’s Institute and University of Arizona College of Medicine in Phoenix, and colleagues conducted a phase 3, randomized discontinuation trial involving patients with psychosis related to Alzheimer disease, Parkinson disease dementia, dementia with Lewy bodies, frontotemporal dementia, or vascular dementia. Patients received 12 weeks of open-label pimavanserin. Those with a response at weeks 8 and 12 were randomly assigned in a 1:1 ratio either to continue receiving pimavanserin or to receive placebo for up to 26 weeks. The primary end point was a relapse of psychosis, assessed in a time-to-event analysis.
The researchers found that 41 of the 392 patients in the open-label phase were withdrawn for administrative reasons because the trial was stopped for efficacy. Of the remaining 351 patients, 217 (61.8 percent) had a sustained response, including 105 and 112 who were assigned to receive pimavanserin and placebo, respectively. A relapse occurred in 13 and 28 percent of patients in the pimavanserin and placebo groups, respectively (hazard ratio, 0.35). Adverse events occurred in 41.0 and 36.6 percent of patients in the pimavanserin and placebo groups, respectively, during the double-blind phase.
“Because the trial was stopped early for efficacy, the ability to assess clinical predictors of relapse is diminished,” the authors write.
The study was funded by Acadia Pharmaceuticals, the manufacturer of pimavanserin.