FDA Panel Supports Eli Lilly Alzheimer's Drug

The FDA's Peripheral and Central Nervous System Drugs Advisory Committee (PCNS) has given unanimous support to Eli Lilly's experimental Alzheimer's medication, donanemab, indicating that the drug's advantages surpass its potential risks for patients in the early stages of the disease. Although the FDA's final decision isn't strictly based on the committee's recommendations, this endorsement suggests a probable approval path.

Earlier in March, Eli Lilly disclosed that the FDA's decision, which was initially expected by the end of that month, had been postponed. The delay occurred as the agency decided it required an additional AdComm meeting to thoroughly examine the safety and efficacy of donanemab. According to Eli Lilly, the PCNS aimed to scrutinize the drug's safety outcomes in treated patients and assess the implications of its unique trial design, particularly the TRAILBLAZER-ALZ 2 study.

The TRAILBLAZER-ALZ 2 trial incorporated a dosing schedule based on amyloid plaque evaluation, allowing patients to cease treatment once these plaques were sufficiently reduced. The study also selected participants based on their tau protein levels. The trial's results were promising, showing a 29% reduction in memory decline in Alzheimer's patients treated with donanemab.

However, the trial raised concerns about ARIA (amyloid-related imaging abnormalities), conditions detectable by MRI such as brain swelling (edema) and microhemorrhages (small brain bleeds). These abnormalities have also been seen in patients taking other Alzheimer's medications, including Biogen's Aduhelm and Eisai's Leqembi. ARIA is critical from a safety perspective because it can lead to severe adverse effects, including death.

Regardless of these safety concerns, including brain swelling and bleeding, the advisory panel appreciated the trial's adaptable treatment approach. This method, which allows for treatment discontinuation once amyloid plaques are cleared, introduces complexities for physicians managing patient treatment schedules.

Donanemab is engineered to target and eliminate beta-amyloid plaques, toxic proteins that build up in the brains of Alzheimer’s patients. The drug binds to these plaques, marking them for removal by the immune system. By lowering the levels of beta-amyloid, donanemab seeks to decelerate the progression of memory and cognitive decline in individuals with early-stage Alzheimer's disease.

The findings from the TRAILBLAZER-ALZ 2 trial and the endorsement from the PCNS suggest that donanemab might soon become a viable treatment option, providing hope to patients and families affected by Alzheimer's. The final decision from the FDA will determine if this promising drug will be available for broader use, potentially changing the landscape of Alzheimer's treatment.