They have been published New Enlgand Journal of Medicine the expected results of the experimentation of lecanemab, a new drug that would slow down cognitive decline in Alzheimer’s patients if administered in the early stages of the disease. It is a monoclonal antibody, developed by Eisai and Biogen, aimed against the amyloid beta protein, which accumulates in the brain of patients to form plaques that play a key role in the degeneration of nervous tissue. In the US, the two companies have already started the process for approving the drug and putting it on the market.
The numbers. The study was conducted in 232 treatment centers in North America, Europe and Asia, and involved 898 patients who received lecanemab for 18 months, and another 897 who followed standard therapy.
At the end of the trial, the drug had slowed the decline of cognitive abilities by 27% and the benefit was accompanied by a reduction in beta amyloid accumulations. “This is the most interesting and advanced experiment among those underway,” comments Giuseppe Di Fede, neurologist, head of the genetics and biochemistry laboratory of dementia at the Carlo Besta Institute in Milan. “For the first time we see not only the reduction of plaques, but also a significant clinical benefit, which is the data that really interests us”.
Side effects. In terms of side effects, the study reports that 13% of patients had cerebral edema and 17% hemorrhages (events recorded respectively in 2% and 9% of those who followed standard therapies). These complications resolved within a few weeks and only resulted in symptoms in 3% of cases.
However, two deaths from cerebral hemorrhage were recorded in patients who had already completed the experimental procedure and were no longer taking the drug. But since the two were no longer part of the trial at the time of their deaths, the data was not included in the newly published study.
A hope? In the light of the results, already anticipated by the two companies in recent weeks, the Lancet magazine spoke of a “hope on the horizon”, for a disease that affects 55 million people worldwide, and around 750,000 in Italy. A hope that will however be confirmed in particular by another study, which will end in 2027, conducted on patients who started therapy when the disease did not yet give any symptoms, but accumulations of beta-amyloid were already present in the brain.
«This is precisely one difficulty» concludes Di Fede, «lecanemab, but also all the other drugs under study, have a greater chance of success if the diagnosis is early and precedes the onset of symptoms. Precisely for this reason, alongside pharmacological research, science is moving to develop tests that allow the identification of the disease to be anticipated as much as possible”.