Study Finds Pimavanserin May Effectively Treat Parkinson Disease Psychosis

The majority of patients with Parkinson disease develop Parkinson disease psychosis (PDPsy); however, pimavanserin may be an effective treatment option for patients, according to a recent study published by Neuropsychiatric Disease and Treatment.

Researchers conducted a systematic review of randomized placebo-controlled trials comparing atypical antipsychotic with a placebo. Databases, including PubMed, the Cochrane Library, ISI Web of Science, and Embase, were searched in order to find 13 randomized placebo-controlled trials with a total of 1142 cases involving pimavanserin, clozapine, olanzapine, and quetiapine.

“Treatment of PDPsy may be difficult due to the modest efficacy of antipsychotics and the risk of worsening motor function. There are several steps involved in the treatment of PDPsy,” noted the authors. “Recently, accessible antipsychotic drugs such as pimavanserin, clozapine, olanzapine, quetiapine have become of common use for the treatment of PDPsy. However, their use is often limited by the resulting adverse drug reactions.”

The review revealed an association with the use of pimavanserin and an improvement in psychotic symptoms compared to the placebo without worsening motor function. Additionally, clozapine was effective in alleviating psychotic symptoms while not exacerbating motor function, according to the results. The study also showed that quetiapine and olanzapine did not demonstrate significant differences in minimizing psychotic symptoms but may have aggravated motor function.

Despite the efficacy of clozapine, the research demonstrated a strong association with adverse events including severe agranulocytosis and mild leukopenia which required frequent drug monitoring. Therefore, the researchers suggested clozapine be recommended but used with caution, while quetiapine and olanzapine should not be considered for first-line medications for treating PDPsy.

“Despite our precise methodology, intrinsic defects such as small size and incomplete data limited us from reaching definitive conclusions. In addition, PDPsy has significant impact on the quality of life of both patients and their family and therefore researches studying the burden caused by the disease are needed,” concluded the authors.

The authors emphasized the need for more well-designed randomized controlled trials in order to expand the research of PDPsy and to confirm the validity of this review.

Reference

Zhang H, Wang L, Fan Y, et al. Atypical antipsychotics for Parkinson’s disease psychosis: a systematic review and meta-analysis [published online July 29, 2019]. Neuropsychiatric Disease and Treatment. doi: 10.2147/NDT.S201029