July 3, 2024
This product is not necessarily endorsed by the Fisher Center Foundation, or our scientists; the article is intended for informational purposes only. Please consult your doctor to see if this, or any other drug, is right for you.
On July 2, 2024, the Food and Drug Administration approved a new drug to treat Alzheimer’s disease. The medication, called Kisunla (pronounced kih-SUHN-lah), is the third of a new class of drugs that are designed to slow the progression of the disease. It is similar to the drug Leqembi, approved last year for certain patients with early Alzheimer’s disease. The FDA approved another drug in this class called Aduhelm in 2021, but because of concerns about its safety and effectiveness, it was pulled from the market.
How effective is Kisunla?
The new treatment may slow declines in memory and thinking skills in those in the early stages of Alzheimer’s, but it cannot reverse memory loss or other symptoms and is not a cure. It is made by the drug company Eli Lilly and was tested under the name donanemab.
Kisunla, like Leqembi, is what is known as a monoclonal antibody, a protein specially designed to recognize a specific target in the body. Both drugs target beta-amyloid, the toxic protein that accumulates in the brains of those with Alzheimer’s disease, forming plaques that are thought to disrupt normal brain signaling. Both drugs help to clear these build-ups of toxic beta-amyloid.
Researchers studied Kisunla in 1,736 men and women in the early stages of Alzheimer’s disease, when declines in thinking and memory skills are somewhat modest. They ranged in age from 59 to 86, with a mean age of 73 years. All had evidence of the telltale plaques of Alzheimer’s in their brains, as well as tau tangles, the spaghetti-like proteins that accumulate and clump inside neurons as the disease progresses.
After 18 months, donanemab slowed declines in thinking and memory skills by about four-and-a-half to seven-and-a-half months compared to study participants who were receiving a placebo drug. Nearly half of those who received donanemab stayed at the same cognitive level one year into the study, compared with less than a third of those who got the placebo.
Benefits were most pronounced in those with the mildest symptoms, in people younger than 75, and in those with the lowest levels of tau in their brains. Most patients who got the drug also showed clearing of the amyloid plaques in their brains.
Importantly, neither Kisunla or Leqembi can reverse or repair damage to the brain that has already occurred, and benefits are modest and may not be noticed by family members.
Who might benefit from Kisunla?
The treatment showed modest benefits in those in the early stages of Alzheimer’s disease and in those with mild cognitive impairment, which often progresses to full-blown Alzheimer’s. But it probably won’t help those with more advanced disease, when damage to the brain has become extensive.
How is the treatment administered?
Kisunla is given as an intravenous injection every four weeks, typically at a clinic or hospital. Infusions typically take about 30 minutes to administer, given through a needle inserted into the arm. (Leqembi is also given by infusion, but every two weeks.) Patients getting the infusions may experience flu-like chills, fever, nausea, swelling of the face, lips or mouth, sweating and other side effects. You will be monitored for at least 30 minutes after you receive Kisunla for any allergic reaction.
Kisunla has a notable difference from Leqembi: Patients can stop taking the drug after PET brain scans show that beta-amyloid levels are minimal. (Patients on Leqembi continue to take the drug.) In the clinical trial, 17 percent of patients were able to stop taking the drug after 6 months, 47 percent stopped after a year, and 69 percent stopped after 18 months.
Cognitive decline may continue to slow even after patients stop taking the drug, though Eli Lilly is testing how long benefits may last.
Is Kisunla safe?
Like Leqembi, the treatment carries risks, including temporary swelling in the brain that may be accompanied by spots of bleeding in or near the brain’s surface. Swelling and bleeding is usually minor and does not cause symptoms, though in rare cases it can be more extensive and potentially be life-threatening. Patients must therefore be monitored closely, and doctors and patients must carefully weigh the benefits and risks of giving the drug. Headache is another common side effect.
Brain swelling and bleeding is more common in people who carry two copies of APOE-E4, a common gene variant that elevates the risk of developing Alzheimer’s. Patients must therefore be tested to determine their APOE-E4 status before starting the drug. Doctors will monitor with MRI brain scans to assess brain bleeding and swelling before and during treatment.
You may be at higher risk of developing bleeding in the brain if you take blood-thinning medicines to reduce blood clots from forming, which doctors commonly prescribe to prevent or treat strokes. Talk to your doctor to see if you are on any medicines that increase this risk.
How much does Kisunla cost?
A year of treatment costs $32,000, compared to $26,000 for Leqembi. Some patients may need to take it for only 6 months (costing $12,522); others will need to continue taking it for 18 months (costing $48,696). Unlike treatment with Leqembi, treatment may be stopped once scans show beta-amyloid has cleared from the brain, which may reduce overall costs.
Brain scans and additional medical care to monitor patients are an additional expense. Medicare may cover some or all of the costs, depending on the patient.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Eric Schmidt, Ph.D. Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Sources: Food and Drug Administration, Eli Lilly
This product is not necessarily endorsed by the Fisher Center Foundation, or our scientists; the article is intended for informational purposes only. Please consult your doctor to see if this, or any other drug, is right for you.