July 12, 2023
On July 6th, the Food and Drug Administration granted full approval to a new treatment for Alzheimer’s disease called Leqembi. The move paves the way for Medicare, the government health insurance plan for older Americans and those with disabilities, to pay for much of the cost of the drug.
In January, the FDA had granted provisional approval to the drug via the Accelerated Approval Pathway. Most of those currently taking the drug were enrolled in clinical trials to test its safety and effectiveness. Full approval is expected to greatly expand the number of Americans who are taking the medication.
“Today’s action is the first verification that a drug targeting the underlying disease process of Alzheimer’s disease has shown clinical benefit in this devastating disease,” said Teresa Buracchio, acting director of the Office of Neuroscience in the FDA’s Center for Drug Evaluation and Research. “This confirmatory study verified that it is a safe and effective treatment for patients with Alzheimer’s disease.”
While older Alzheimer’s drugs may ease symptoms for a time, they do nothing to stop the relentless downward course of the disease. Leqembi (pronounced le-KEM-bee) is the second of a new class of drugs that are designed to slow the progression of the disease. In 2021, the FDA had given fast-track approval to another drug called Aduhelm, but many doctors questioned the effectiveness of that drug, and Medicare greatly limited who could be reimbursed for taking it.
How effective is Leqembi?
The new treatment may slow declines in memory and thinking skills in those in the early stages of Alzheimer’s disease, but it is not a cure. It cannot reverse the course of the disease or stop it from ultimately getting worse. But data from a large clinical trial suggests that the drug — administered every two weeks as an intravenous infusion — may slow decline by about five months over about 18 months for people with mild symptoms.
Still, some experts say that it is unclear from the evidence whether the drug’s effects would even be noticeable to patients or their families. In studies in nearly 1,800 patients over 18 months, patients scored about a half-point higher on an 18-point scale of memory and thinking skills. It’s unknown whether the treatment may have benefits over longer periods; continued testing is underway.
How does Leqembi work?
The drug is what’s known as a monoclonal antibody, designed to target and clear the beta-amyloid plaques that build up in the brains of those with Alzheimer’s disease. The FDA instructs doctors to perform brain scans to confirm whether patients have an accumulation of the toxic protein in their brains before they be given the drug. Leqembi is made by the drug companies Eisai and Biogen, and was tested under the name lecanamab.
Who might benefit from Leqembi?
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. People in the early stages of Alzheimer’s disease can typically carry out everyday activities like getting dressed and preparing meals. About a quarter of those with Alzheimer’s are thought to be in the early stages of the disease.
But it probably won’t help those with more advanced disease, when damage to the brain has become extensive. The company that makes the drug recommends patients stop using it once they progress from mild to moderate Alzheimer’s disease. Nor would Leqembi be expected to help those who have dementia that is not caused by the amyloid plaques of Alzheimer’s.
How is the treatment administered?
Leqembi is given as an intravenous injection every two weeks, typically at a clinic or hospital. Patients getting the infusions may experience flu-like chills, fever and other side effects.
Is Leqembi safe?
Leqembi, like monoclonal antibodies in general, carries risks. In tests, about 13 percent of people receiving the medication showed evidence of brain swelling, compared to less than 2 percent taking a placebo. About 17 percent had small bleeds in the brain, compared to about 9 percent of those in the placebo group. Brain bleeds and swelling may or may not cause symptoms such as headaches or dizziness, depending on their severity. Several people who were receiving the drug have died of brain hemorrhages, including two who were also taking blood thinning medications. Therefore, patients may need to be monitored with brain scans to assess brain bleeding and swelling.
People taking blood thinners, which doctors commonly prescribe to prevent or treat strokes, should therefore be warned that they are at higher risk of brain bleeds and brain swelling. Those who already have evidence of four or more brain bleeds are also at increased risk, as are patients who carry the APOE-e4 gene variant, which increases the risk of developing Alzheimer’s. Those who carry two copies of the APOE-e4 gene are at particularly high risk of serious side effects. Doctors are therefore advised to perform genetic testing to determine whether someone carries the gene variant.
How much does Leqembi cost?
Medicare will cover 80 percent of the drug’s $26,500 yearly cost. Patients will be responsible for the remaining 20 percent, or more than $5,000 a year. That’s on top of any additional costs for administering the medication intravenously at clinics, as well as any follow-up testing and scans. Some experts estimate the total costs of treatment and monitoring may run up to $90,000 a year. It is unknown at this time whether Medicare or other health insurance plans will cover some or all of these additional costs.
Who is eligible to be covered for Leqembi?
Medicare is requiring that doctors who prescribe Leqembi must submit detailed medical information about each patient before they get the drug and while they are being treated. Physicians must be trained and enter a registry to provide information about the drugs benefits and harms, which may limit the number of doctors and clinics administering the drug.
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.
Source: Food and Drug Administration, Esai, Biogen