FDA delays Eli Lilly Alzheimer's drug decision with last-minute AdComm

The FDA will convene an unexpected advisory panel meeting to discuss the phase 3 trial of Eli Lilly's donanemab in early symptomatic Alzheimer's disease, delaying the anticipated decision on the drug's approval.

According to Lilly, the Peripheral and Central Nervous System Drugs Advisory Committee wants to dig deeper into the safety and efficacy of donanemab, looking closely at the safety results in donanemab-treated patients and the efficacy implications of the unique trial design of the TRAILBLAZER-ALZ 2 study, including its limited-duration dosing regimen that allowed patients to complete treatment based on an assessment of amyloid plaque and the inclusion of participants based on tau levels.

As of now, the date of the advisory committee meeting for donanemab hasn't been set by the FDA, which means the agency's approval decision, which was expected by the end of March, will be delayed beyond the first quarter of 2024, said Eli Lilly.

This is the second time trial design has triggered a regulatory setback for the beta-amyloid targeting antibody. Earlier this year, the FDA rejected Eli Lilly’s bid for accelerated approval, issuing a complete response letter, forcing the drugmaker to seek traditional approval. In the phase 2 TRAILBLAZER-ALZ 2 study, which included 272 patients, patients stopped receiving donanemab and switched to placebo once their plaque reached a certain level for clearance. In the CRL, the FDA specifically requested that Lilly provide data from at least 100 patients who received a minimum of 12 months of continued treatment on donanemab.

Despite the setback, Eli Lilly seems confident that donanemab will ultimately win approval. "While it is unusual for an advisory committee to occur after the anticipated FDA action date, the advisory committee meeting for donanemab follows similar meetings for the two other amyloid plaque-targeting therapies the FDA has approved," the company said in its press release.