The Food and Drug Administration (FDA) is delaying approval of a new Alzheimer’s drug from Eli Lilly, and it instead will require the company to face an advisory panel to scrutinize its safety and effectiveness data, the company said Friday.
“The FDA has informed Lilly it wants to further understand topics related to evaluating the safety and efficacy of donanemab, including the safety results in donanemab-treated patients and the efficacy implications of the unique trial design,” Lilly said in a statement.
FDA’s decision came as a surprise to the company. Lilly submitted its traditional approval application of donanemab to the FDA last year and anticipated getting the green light by early 2024.
FDA hasn’t yet set a date for the meeting, but the timing of the expected FDA action on donanemab would be delayed beyond the first quarter.
“It was unexpected to learn the FDA will convene an advisory committee at this stage in the review process,” said Anne White, executive vice president of Eli Lilly and Company and president of Lilly Neuroscience, in a statement. “We will work with the FDA and the stakeholders in the community to make that presentation and answer all questions.”
While it is unusual for an advisory committee to convene after an anticipated FDA action date, the advisory committee meeting for donanemab follows similar meetings for the other amyloid plaque-targeting therapies the FDA has approved.
FDA doesn’t have to follow the recommendation of its advisory committees, but it often does. The agency notably approved a different Alzheimer’s drug, the ill-fated Aduhelm in 2021, despite a negative advisory committee vote.
More than 6 million people in the United States are diagnosed with Alzheimer’s, and that number is expected to rise as the population ages. There is no cure, but there are about 1 million people with early-stage disease who could benefit most from the drug.
Donanemab would be the second successful Alzheimer’s drug on the market after the FDA last year approved Biogen and Eisai’s Leqembi. The late-stage clinical trial data from Lilly was similar to the data cited by the FDA when it approved Leqembi, which is why the company expected an easy approval for the potential competitor.
Donanemab is a monoclonal antibody that targets a brain plaque called amyloid. It’s administered every four weeks by intravenous infusion. Leqembi is given every two weeks to modestly slow cognitive decline in the early stages of Alzheimer’s.
The drugs can significantly reduce the levels of plaque, but questions remain about the clinical significance and degree of benefit.
According to Lilly, donanemab slowed Alzheimer’s disease progression by 35 percent relative to placebo treatment, in an 18-month clinical trial that enrolled 1,700 patients with early-stage disease. In practical terms, that translated to delaying progression by about four months.
There were serious risks identified in the trial, raising concerns that the risk outweighed the benefit. Three people died after developing serious brain bleeding or swelling.
The Centers for Medicare and Medicaid Services has said Medicare will cover Alzheimer’s drugs — as long as they receive full FDA approval and companies gather data on how the drugs work in the real world.