NATIONAL INSTITUTE ON AGING, NIH/AP
An experimental drug that removes a substance called amyloid from the brain appears to slow Alzheimer’s disease.
The drug, called lecanemab, reduced the rate of cognitive decline by 27% in a study of nearly 1,800 people in the early stages of Alzheimer’s disease, scientists reported at the clinical trials meeting on the disease. of Alzheimer’s in San Francisco.
The study was published simultaneously in The New England Journal of Medicine.
People who received lecanemab infusions did about half a point better on a mental functioning scale of zero to 18 points, a small but statistically significant difference.
The results are “real and robust,” says Dr. Christopher van Dyck, who heads the Yale Center for Alzheimer’s Disease Research and presented an overview of the study at the meeting.
But Dr Madhav Thambisetty of the National Institute on Aging, who was not involved in the study, called the results a “very small effect”.
“These differences are highly unlikely to be noticeable by individual patients in their daily lives,” says Thambisetty.
Thambisetty emphasized that his opinions are his own and that he does not speak on behalf of the NIA, which is part of the National Institutes of Health.
About one in five people who received lecanemab in the study experienced an adverse event, such as swelling or bleeding in the brain. People have also reported symptoms, including headaches, visual disturbances and confusion.
The treatment has been linked to two deaths.
But most side effects are “mild to moderate,” says Dr Marwan Sabbagh of the Barrow Neurological Institute, who gave a presentation on the safety of lecanemab. And the number of abnormalities detected on brain scans was “within expectations”, he says.
Even so, lecanemab is “not a benign drug,” says Thambisetty, adding that its risks may outweigh its benefits for some patients.
Lecanemab is developed by the Japanese company Eisai with the American company Biogen.
Lecanemab’s apparent success comes after many years of frustration and failure for companies developing drugs designed to remove amyloid from the brain.
So far, only one amyloid drug, Aduhelm, has received Food and Drug Administration approval.
This drug, also developed by Eisai and Biogen, was approved in 2021 despite conflicting evidence about its effectiveness, and after an FDA advisory committee voted against approval.
Sales of Aduhelm have been slow, largely because Medicare will only cover the drug for patients in a clinical trial.
But Alzheimer’s patients and their families are already anticipating the arrival of lecanemab, despite its limitations.
“I am a person living with a progressive and fatal disease,” says Michael Zuendel, 68, who has been taking Aduhelm since being diagnosed with mild cognitive impairment, an early stage of Alzheimer’s disease. “I don’t have time to wait for the perfect research study.”
“I’m hopeful that the FDA will approve [lecanemab]“, says Zuendel.
The Food and Drug Administration is expected to issue a decision by January 6, 2023.