Eli Lilly's Alzheimer's Drug Approval Decision Delayed by FDA for Safety Review

Eli Lilly, a pharmaceutical company, announced on Friday that the Food and Drug Administration (FDA) has postponed its decision deadline for the potential approval of the experimental Alzheimer's treatment donanemab. This unexpected move comes as the agency plans to convene a last-minute meeting of its external advisors to conduct a thorough review of the treatment's safety and efficacy in a late-stage trial.

Implications of the FDA's Decision

The FDA's decision to call for an advisory meeting underscores the high stakes involved in developing treatments for Alzheimer's disease, which currently affects over six million Americans and has no known cure. The delay in the approval decision is a setback for Eli Lilly, as it competes with other pharmaceutical companies in the race to provide effective care options for Alzheimer's patients.

Eli Lilly's Response

Eli Lilly expressed confidence in the potential benefits of donanemab for individuals with early symptomatic Alzheimer's disease, despite the unexpected delay. The company emphasized its commitment to working with the FDA and the wider community to address any concerns and present the treatment's capabilities.

Comparison with Competing Treatments

Eli Lilly's drug, like another approved treatment from Biogen and Eisai called Leqembi, is a monoclonal antibody targeting the buildups of a protein in the brain known as amyloid plaque, which is a key characteristic of Alzheimer's disease.

Advisory Panel Meeting

It is uncommon for the FDA to hold an advisory panel meeting after a set action date, but the agency has previously convened similar meetings for two other therapies targeting amyloid plaque. The FDA often seeks advice from its advisory panel on the safety and effectiveness of unapproved products, although it is not obligated to follow their recommendations.

Examination of Clinical Trial Data

The FDA will examine an 18-month phase three trial that involved over 1,700 patients in the early stages of Alzheimer's with confirmed amyloid plaque presence. The focus will be on understanding the safety results and the trial's unique design and its impact on efficacy.

Clinical Trial Results

Eli Lilly's study demonstrated positive results, showing a 35% slower decline in memory, thinking, and daily functioning in patients who received the drug compared to those who did not. However, the trial also revealed that a significant proportion of individuals who took donanemab experienced brain swelling or bleeding, including fatal cases, compared to those who received a placebo. Similar side effects have been observed in the competing treatment, Leqembi.