Pimavanserin shows good efficacy, safety in older adults with Parkinson’s

Key takeaways:

• Treatment with pimavanserin resulted in improvement at week 8 compared with the placebo group.
• Rates of adverse events were similar in both the pimavanserin group and placebo group.

Pimavanserin was well-tolerated and not associated with cognitive decline or motor dysfunction in older adults with Parkinson’s disease and neuropsychiatric symptoms, according to a poster presentation.

“Most patients with a neurodegenerative disease, such as Parkinson’s disease, will experience neuropsychiatric symptoms, such as hallucinations and delusions, apathy and agitation, at some point over the course of their disease,” Gustavo Alva, MD, DFAPA, an assistant clinical professor in the department of psychiatry and neuroscience, University of California, Riverside, and colleagues wrote in the poster presented at the Alzheimer’s Association International Conference.

Alva and fellow researchers aimed to assess safety and efficacy of pimavanserin compared with placebo in frail older adults and other elderly individuals with neuropsychiatric issues stemming from disease progression.

They conducted a multicenter, randomized, double-blind, placebo-controlled phase 3b clinical trial that included 784 individuals (median age 72.4 years; 57.8% female; 93.8% white) from an initial 1,440 screened. Participants were aged 60 years and older, had been diagnosed with a neurodegenerative disease and needed assistance with daily life and activities but were able to provide written informed consent. Participants were randomized 1:1 to receive either 34 mg pimavanserin or placebo for up to 8 weeks. Data were analyzed to determine a primary endpoint of safety measured by treatment-emergent adverse effects, as well as secondary endpoints of change in the Extrapyramidal Symptom Rating Scale (ESRS-A) and Mini-Mental State Examination (MMSE) scores from baseline to study conclusion. Change from baseline to week 8 on the EQ-5D-5L visual analog scale questionnaire was also measured and patient assessments were scheduled at weeks 1, 2, 4, 6 and 8.

A total of 730 individuals completed the study and 54 decided to terminate before its completion.

Alva and colleagues found no significant differences between the treatment and placebo groups with respect to the ESRS-A or MMSE from baseline to week 8 for cognition or efficacy; however, at week 8, a significant difference was observed in the pimavanserin group using the Clinical Global Impression-Improvement scale (-0.2 [0.07]; P = 0.0140).

Serious treatment-emergent adverse events were recorded in 14 participants, while 19 participants reported TEAEs that led to treatment discontinuation, with the most frequent being urinary tract infection and headache. Mortality was reported in four participants.

“These results further add to our knowledge of the safety of pimavanserin for patients with [Parkinson’s disease psychosis],” Alva and colleagues wrote.