Shares of ACADIA Pharmaceuticals are soaring in premarket trading after the company announced full positive results from its Phase III HARMONY study evaluating Nuplazid (pimavanserin) for the treatment of dementia-related psychosis. The stock is up more than 20% to $53.26.
Acadia stopped the HARMONY trial early in September following a pre-planned interim analysis after Nuplazid hit the primary endpoint of significantly reducing the risk of relapse of psychosis compared to placebo. In fact, the company is excited that the data shows patients on Nuplazid are nearly three-times less likely to have a psychosis relapse than placebo patients. In addition to hitting the primary endpoint, Nuplazid hit the key secondary endpoint of significantly reducing the risk of discontinuation for any reason. With the trial results, Acadia plans to head to the U.S. Food and Drug Administration to seek regulatory approval early next year. The FDA previously granted Breakthrough Therapy Designation for pimavanserin for the treatment of dementia-related psychosis.
The company presented full trial data at the 12th Clinical Trials on Alzheimer’s Disease meeting in San Diego on Wednesday. Serge Stankovic, president of Acadia, hailed the HARMONY study as a landmark in dementia-related psychosis.
“The HARMONY study was designed to answer three very important questions. First, in the 12-week open-label period, pimavanserin treatment showed a meaningful reduction of the symptoms and stabilization of psychosis across all of the five clinically diagnosed subtypes evaluated. Second, in the 26-week double-blind period, patients on pimavanserin had a nearly three-fold reduction of risk of relapse compared to patients on placebo. And third, pimavanserin was well-tolerated by elderly patients with dementia-related psychosis,” Stankovic said.
Nuplazid is a selective serotonin inverse agonist and antagonist preferentially targeting 5-HT2A receptors. Nuplazid is approved to treat psychosis related to Parkinson’s disease. In July, Nuplazid failed to hit statistical significance in a Phase III schizophrenia trial. Patients in the ENHANCE trial showed a consistent trend in symptom improvement but did not hit statistical significance on the primary endpoint.
A total of 392 patients with an average age of 74 were enrolled in the HARMONY study. The patients had an average baseline of moderate-to-severe psychosis as measured by the Scale for the Assessment of Positive Symptoms-Hallucinations and Delusions (SAPS-H+D). Over the course of treatment, randomized patients who took Nuplazid saw their SAPS-H+D score improved by 63% and 75.2% respectively.
Jeffrey Cummings, director emeritus of Cleveland Clinic Lou Ruvo Center for Brain Health in Las Vegas said the results of the HARMONY trial are an important advance for dementia-related psychosis treatment, as there are currently no FDA-approved treatments available. Cummings pointed to the three-fold data and said reducing the risk of relapse of psychotic symptoms by that magnitude is an “important and meaningful outcome.”
It is estimated that about 2.4 million people in the United States, about 30% of the 8 million dementia patients, have psychosis, which commonly includes delusions and hallucinations. Dementia-related psychosis includes psychosis in Alzheimer’s disease, dementia with Lewy bodies, Parkinson’s disease dementia, vascular dementia, and frontotemporal dementia.
Nuplazid was well-tolerated during the study with a low rate of adverse events observed.
