FDA approves Alzheimer's drug shown to slow decline in memory, cognition in those with the disease

The U.S. Food and Drug Administration has approved an Alzheimer's drug that's been proven to slow memory and cognitive decline in patients with the disease.

The approval Tuesday clears the way for adults with early or mild symptomatic Alzheimer's to be treated with Eli Lilly and Company's drug donanemab, under the name brand Kisunla, a once-monthly IV infusion that works by targeting amyloid in the brain.

The body naturally produces the protein amyloid, but when it clumps together to create amyloid plaques, an excessive buildup can affect bodily organs and tissue. And in the brain, that leads to memory and cognitive issues that are associated with Alzheimer's disease.

Kisunla , according to Eli Lilly, was shown in promising clinical trials to help the body remove amyloid plaque buildup and, therefore, significantly slow the decline of multiple brain functions affected by Alzheimer's, including a person's ability to "remember new information, important dates, and appointments, plan and organize, make meals, use household appliances, manage finances and be left alone," Eli Lilly said.

Participants in the Kisunla trial saw an average reduction in amyloid plaques by 61% at six months and 80% at 12 months. Eighteen months after the start of the trial, the buildup was 84% reduced, and the once-monthly infusions were shown to have slowed cognitive and functional decline by up to 35% compared to the placebo. Up to 39% of participants also saw a reduced risk in progressing to the next clinical stage of the disease.

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This is only the second time the FDA has approved a drug to treat Alzheimer's following successful clinical trials. Last year, the federal agency approved Leqembi, another IV-administered drug that targets amyloid plaque buildup.

It's unclear which drug will be more beneficial for patients, but Eli Lilly said another benefit to its treatment shown through the trial is that participants were able to complete treatment once amyloid plaque levels were shown to be reduced to minimal levels. Eli Lilly said that makes Kisunla the only amyloid plaque-targeting therapy that's proven to support stopping therapy at a certain point, which can lower treatment costs and reduce the number of infusions a patient needs.

The cost of Kisunla will vary depending on the patient and the length of their treatment period, but Medicare is expected to provide coverage. Eli Lilly does have a free support program that can help patients determine their coverage assistance and coordinate care, found at Kisunla.Lilly.com .

There are still potentially life-threatening side effects with the amyloid-targeting drugs, like brain swelling and bleeding, that patients and their families will have to weigh before deciding to undergo treatment.

An estimated 6.9 million Americans age 65 and older have Alzheimer's, according to 2024 data from the Alzheimer's Association . But the group projects the number to grow to 12.7 million by 2050 as the age group's population grows.