FDA Approves New Alzheimer’s Treatment

Researchers leading the 18-month-long trial found that Alzheimer’s symptoms did not worsen after a year of treatment for nearly half of participants who received Kisunla, compared with 29 percent who received a placebo. The study results suggest that people may not need the treatment indefinitely; patients in the study were taken off the drug once a certain amount of amyloid was removed from the brain.

“It’s encouraging to see that some patients essentially enter remission, where they achieve full amyloid clearance with donanemab, with no resurgence in substantial plaque buildup for nearly four years,” Howard Fillit, M.D., cofounder and chief science officer of the Alzheimer’s Drug Discovery Foundation, said in a recent statement.

How long that state of remission lasts and what it means for the progression of Alzheimer’s symptoms is unclear, said Lawrence Sterling Honig, M.D., a professor of neurology at Columbia University Irving Medical Center and a neurologist at NewYork-Presbyterian.

Expanding options for patients and physicians

Jagan Pillai, M.D., an Alzheimer’s expert at the Cleveland Clinic Lou Ruvo Center for Brain Health in Cleveland, called Kisunla’s approval “a huge impetus to the field.” Adding another Alzheimer’s medication to the mix is “exciting” for patients and their loved ones, he said, “mostly because it gives them a range of choices to pursue therapeutic options in this area.”

Although Leqembi and Kisunla are in the same drug class, “it's always good to have more than one choice,” Honig echoed.

Both anti-amyloid medications are administered by an IV infusion: Leqembi is given twice monthly, and Kisunla is administered once a month. (Leqembi’s manufacturer seeks FDA approval on an injectable form of the medication.)

Side effects reported in the Kisunla trial were similar to those seen with Leqembi, swelling and bleeding in the brain being the chief concerns.

Often these events are small, temporary and asymptomatic, but larger bleeds can occur and can be serious, even fatal. Three study participants died from these effects. “These are side effects that require MRI monitoring, for both drugs,” Honig said.

Kisunla’s maker, Eli Lilly, priced the drug at $32,000 a year, higher than Leqembi’s $26,500 annual list price, though costs will vary depending on how long someone takes the drug. Out-of-pocket expenses will depend on an individual’s insurance.

Medicare will cover Alzheimer’s treatments that are FDA-approved for people who meet certain criteria, including having confirmed presence of amyloid plaques. Patients are required to work with a health care provider who participates in a registry to collect information on the safety and effectiveness of the medication.

Despite many similarities, there are a handful of differences between Leqembi and Kisunla. Choosing which to take “is something that is for patients to discuss with their neurology practitioners,” Honig said.

It’s unclear when Kisunla will be widely available; Pillai and Honig predict the rollout will take a few to several months.

Search for Alzheimer’s treatments continues

Even after this latest medication approval, the search for effective Alzheimer’s treatments continues.

Hundreds of potential treatments are being studied, including by the AARP-backed Dementia Discovery Fund, and many have targets other than amyloid. The Cleveland Clinic’s Pillai said experimental therapies targeting tau, another hallmark of Alzheimer’s disease, are among the more exciting discoveries happening. “And there’s a lot of interest in targeting other changes going on,” he said.

“Alzheimer’s disease and related dementias are complex disorders, caused by a constellation of overlapping and intertwined chains of biochemical reactions that wreck the brain,” Richard J. Hodes, M.D., director of the National Institute on Aging, said in a statement. “Successfully treating each individual’s dementia will likely require a diverse set of preventative and diagnostic therapies. The data reported in these donanemab and lecanemab studies suggest that anti-amyloid therapies may, at least, be the first of many other treatments.”

Editor’s note: This story, first published July 18, 2023, has been updated to include new information.