With FDA AdComm on the books, Acadia sees glimmer of hope in 2nd stab at Alzheimer's psychosis

An FDA advisory committee meeting usually means an additional hurdle for a drug approval. But for Acadia Pharmaceuticals’ once-rejected Nuplazid label expansion bid, it could represent a hard-fought opening for a possible green light.

The FDA has accepted a resubmitted application for Nuplazid for treating hallucinations and delusions associated with Alzheimer’s disease psychosis, Acadia said Wednesday. Before the agency makes an approval decision by Aug. 4, it plans to gather a group of external experts to weigh in during an advisory committee meeting, the San Diego company added.

The meeting “could be an important positive” for Acadia’s application, Mizuho analyst Vamil Divan, M.D., said in a Wednesday note to clients. Given the FDA has expressed concerns about Acadia’s data, “the more external input (and potentially support) that can be considered during the review process the better,” he said.

Acadia had previously sought a wider psychosis label expansion based on data from the phase 3 Harmony trial. But the FDA rejected the drug and asked for another clinical trial to better understand Nuplazid’s effect in each psychosis subgroup.

After multiple meetings with the agency, Acadia recently refiled an application focused on the Alzheimer’s population, who represent about 70% of the overall dementia-related psychosis patient pool. About 30% of patients with Alzheimer’s disease experience psychosis, and there’s no FDA-approved treatment for it.

Instead of conducting another study, the company is using a subgroup analysis of Harmony—which isn’t statistically powered—and a phase 2 study dubbed Study-019 done specifically in Alzheimer’s psychosis patients for its second try.

The move comes with some uncertainties, notably that the FDA has specifically said it would rather see a new trial, according to Acadia. Mizuho’s Divan also said he’s “somewhat skeptical” that the FDA will approve Nuplazid based on existing data.

On the flip side, responses from experts since the release of Harmony data “have generally been quite positive on Nuplazid’s potential in [Alzheimer’s disease psychosis], especially given the lack of other approved medications for this condition,” the Mizuho analyst said.

Key topics that could be discussed at the upcoming meeting could cover efficacy from the two clinical trials, as well as the benefit-risk profile of Nuplazid “in the context of current treatment paradigm and off-label use of antipsychotics in this patient population, RBC Capital Markets analyst Gregory Renza said in his Wednesday note after speaking with Acadia management.

Renza said he remains optimistic about the outcome given “the hints of receptivity” from the FDA, his team’s analysis and Acadia management’s work going into the review.