FDA issues complete response letter for pimavanserin for dementia-related psychosis

Acadia Pharmaceuticals has received a complete response letter from the FDA stating that the administration cannot approve a supplemental new drug application for pimavanserin.

The application sought approval for pimavanserin (Nuplazia, Acadia) for treating hallucinations and delusions associated with dementia-related psychosis.

“Acadia stands behind the robustly positive results from the pivotal Phase 3 HARMONY study and the prospectively agreed trial design and criteria for establishing efficacy in [dementia-related psychosis],” Steve Davis, CEO of Acadia, said in a press release. “Over the entire course of the review, the [Division of Psychiatry] did not raise any concerns regarding the agreed upon study design, including the issues raised in the [complete response letter]. We will immediately request a Type A meeting to work with the FDA to address the [complete response letter] and determine an expeditious path forward for the approval of pimavanserin in [dementia-related psychosis].”

The FDA’s Division of Psychiatry noted in the complete response letter a lack of statistical significance among certain dementia subgroups, as well as insufficient numbers of patients with certain less common dementia subtypes, for its decision to not support approval. According to the Acadia press release, these factors listed by the FDA were not among prespecified requirements for approval. Further, the release noted the dementia-related psychosis pivotal HARMONY study met prespecified primary and secondary endpoints, and its evidence demonstrated clinical and statistical superiority of pimavanserin over placebo — a prerequisite prospectively agreed upon for the dementia-related psychosis indication.

In the complete response letter, the Division of Psychiatry also cited a supportive phase 2 study in the supplemental new drug application filing that focused on Alzheimer’s disease psychosis to not be adequate and well controlled.

The complete response letter made no mention of safety issues or concerns.

UsAgainstAlzheimer’s, a nonprofit organization that supports Alzheimer’s disease research, released a press release denouncing the FDA’s decision regarding pimavanserin.

“We are extremely frustrated and disappointed that the FDA has failed to approve pimavanserin, which would have been the first therapy to treat dementia-related hallucinations and delusions,” George Vradenburg, chairman and co-founder of UsAgainstAlzheimer’s, said. “This drug was found to be safe and effective in a Phase 3 clinical trial whose study design was approved by the FDA. And this drug was approved as safe and effective — and has been used for years — in people experiencing Parkinson’s-related psychosis.

“UsAgainstAlzheimer’s urges Acadia and the FDA to meet as soon as possible to find a path forward for this drug’s expeditious approval,” Vradenburg added.

References:

Acadia Pharmaceuticals Inc. Acadia pharmaceuticals receives complete response letter from U.S. FDA for supplemental new drug application for pimavanserin for the treatment of hallucinations and delusions associated with dementia-related psychosis. Accessed April 5, 2021. Available at: https://www.businesswire.com/news/home/20210405005229/en/Acadia-Pharmaceuticals-Receives-Complete-Response-Letter-from-U.S.-FDA-for-Supplemental-New-Drug-Application-for-Pimavanserin-for-the-Treatment-of-Hallucinations-and-Delusions-Associated-with-Dementia-Related-Psychosis.

UsAgainstAlzheimer’s. UsAgainstAlzheimer’s statement on FDA failure to approve Acadia drug for treatment of dementia-related hallucinations and delusions. Accessed April 5, 2021. Available at: https://www.usagainstalzheimers.org/press/usagainstalzheimers-statement-fda-failure-approve-acadia-drug-treatment-dementia-related.