After suffering a surprise rejection from the FDA in April, Acadia Pharmaceuticals is making another bid to expand the scope of its Parkinson’s disease med Nuplazid—and it hopes to do so without running additional trials.
Acadia plans to resubmit its application for Nuplazid, also known as pimavanserin, to treat hallucinations and delusions associated with dementia, homing in specifically on patients with Alzheimer’s disease psychosis (ADP), the company said early this week. The San Diego-based company is targeting the first quarter of 2022 for its resubmission.
By “narrowing” the drug’s prospective indication from dementia-related psychosis (DRP) to ADP, Acadia hopes to clinch a Nuplazid label expansion without running more studies, which the FDA recommended in its complete response letter (CRL) this spring.
At the time it received the letter, Acadia said the agency's decision was “very disappointing” and that it “strongly" disagreed with the move. The drugmaker argued that the regulator suddenly shifted its stance despite a prior agreement that had been in place for several years.
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For its part, the FDA’s psychiatry division had issues with the design of the phase 3 HARMONY trial Acadia used to support Nuplazid’s DRP application.
“Following our recent meetings with the FDA, we plan to resubmit our sNDA for pimavanserin, narrowing the proposed indication from dementia-related psychosis to Alzheimer’s disease psychosis,” Steve Davis, Acadia’s CEO, said in a statement.
That resubmission will hinge on new analyses of two existing trials—HARMONY and another study dubbed -019, the company said.
“We are aware there are challenges to overcoming our complete response letter,” Davis continued, adding that the company was “pleased with the high level of engagement from the FDA over the last three meetings and their willingness to review our resubmission, allowing us to make our case that pimavanserin should be the first drug approved to treat Alzheimer’s disease psychosis.”
Analysts aren’t shying away from those challenges, either. Berenberg Capital Markets’ Esther Hong told clients Tuesday she was concerned the FDA would stick by its requirement for additional studies, as outlined in the CRL.
“This would likely dramatically increase the capital required and time to launch,” Hong’s team wrote. Still, the analysts added that Acadia’s data look positive and could support an approval.
Hong said her team at Berenberg would be more “constructive” if the FDA telegraphed its willingness to accept data from Acadia’s existing trials.
When Nuplazid clinched a phase 3 win in the HARMONY study in late 2019, SVB Leerink analyst Marc Goodman forecast peak sales in the DRP indication of $2.5 billion. With a narrower focus on Alzheimer’s, the drug’s potential cash haul is sure to be lower.
The resubmission should demonstrate Nuplazid’s benefit in ADP patients, without worsening of cognition or motor function, Acadia predicts. Both HARMONY and the -019 study met their primary endpoints. The company will also supply the regulator with additional analyses of the studies “that validate the primary conclusions from each study and address the concerns raised in the FDA’s complete response letter.”