Nuplazid effectively treats psychosis in Parkinson’s dementia patients
Significantly lower risk of relapse seen with drug's daily use in Phase 3 trial
This finding “supports the maintenance of antipsychotic efficacy and safety of [Nuplazid] in patients with Parkinson’s disease dementia and psychosis,” the researchers wrote.
Their study, “Pimavanserin for psychosis in Parkinson’s Disease dementia: Subgroup analysis of the HARMONY Trial,” was published in Parkinsonism and Related Disorders and supported by funding from Acadia Pharmaceuticals, which markets Nuplazid.
Nuplazid is approved in the US to treat Parkinson’s-related psychosis
Parkinson’s psychosis is marked by hallucinations (hearing or seeing things that aren’t there) and/or delusions (fixed beliefs with no basis in observable reality). Patients may experience psychosis as a nonmotor symptom of the disease.
Nuplazid is an oral therapy that’s approved in the U.S. to treat Parkinson’s-related psychosis in patients with or without dementia.
The Phase 3 HARMONY (NCT03325556) trial tested Nuplazid as a treatment for psychosis related to dementia in Parkinson’s or other disorders.
The study enrolled more than 300 people, all of whom underwent three months of treatment with the therapy, given at a 34 mg dose once daily. Based on tolerability, a dose reduction to 20 mg daily was permitted.
Patients who responded to the therapy then randomly were assigned to continue on Nuplazid or to switch to a placebo. The study’s main goal was to see if patients who stayed on Nuplazid were less likely to have a relapse or a worsening of psychosis symptoms.
In this study, scientists reported the outcomes for 59 trial participants who specifically had Parkinson’s. Their mean age was 72.6, and 16 patients (32.7%) exhibited mild dementia, 28 (57.1%) moderate dementia, and five (10.2%) severe dementia by investigator assessment, the scientists reported.
After HARMONY’s initial three months of treatment to identify potential responders, 36 of these patients entered into its placebo-controlled part, and efficacy data were available for 30 of them: 13 patients given Nuplazid and 17 on a placebo.
Researchers highlighted that “the majority of patients met the prespecified treatment response criteria for an improvement in symptoms of psychosis over 12 weeks of open-label treatment” in the study’s initial part.
As of the cutoff for this analysis, with an average of more than three months of follow-up during Nuplazid or placebo use, one of the 13 patients given Nuplazid had experienced a psychosis relapse, whereas nine of the 17 patients on a placebo had relapsed.
Statistical analyses showed a significantly lower risk of relapse with Nuplazid than a placebo. This was true for participants who received Nuplazid at 34 mg as well as those who reduced their dose to 20 mg.
Safety data from the trial were consistent with the known safety profile of Nuplazid, and the therapy did not have a negative effect on scores of cognition or motor function. The most commonly reported side effects in clinical trials of Nuplazid were swelling in the legs or arms and confusion.
“Collectively, our findings are consistent with prior data which led to the approval of [Nuplazid] for the treatment of psychosis associated with [Parkinson’s],” the researchers concluded.
Nuplazid targets a group of receptors, called serotonin 5-HT2A receptors, known to play an important role in psychosis, schizophrenia, depression, and other neuropsychiatric disorders. The therapy is a selective serotonin inverse agonist (SSIA), meaning it binds to these receptors. But instead of activating them, it blocks their activity.
Three of this study’s seven authors are employees of Acadia Pharmaceuticals.