The results, presented in connection with an Alzheimer’s conference in San Francisco, confirm the preliminary information that the company behind the experimental drug lecanemab announced in September.
Now the entire study has been published in the scientific journal New England Journal of Medicinewhich also means that the results have been reviewed by other researchers.
In the study, lecanemab was tested in a group of 1,800 patients aged 50 to 90 with early Alzheimer’s. Participants were randomized to receive infusions of either lecanemab or placebo every two weeks.
Less deterioration
After an 18-month follow-up, it was found that the treatment had slowed the cognitive decline that occurs in Alzheimer’s patients. The researchers describe the effect as “modest”.
The effect was measured according to a special scale, CDR-SB. The participants who had received the antibody lecanemab had 0.45 points less deterioration on the scale compared to those who received the placebo.
The scale runs from 0 to 18, with higher scores corresponding to worse dementia. The scale measures both cognitive function and how the person functions in everyday life.
At the same time, the drug more often gave rise to certain side effects. More people in the drug group were affected by ARIA – a kind of brain change that can be seen on an image – than in the placebo group. For example, 12.6 percent in the lecanemab group experienced swelling or effusion compared to 1.7 percent in the placebo group.
Patient died
Just days before the results were presented, the journal Science published information on its website about a patient who received the treatment and who died. The patient reportedly suffered a stroke, with a type of swelling and bleeding previously seen with a similar type of antibody that binds to and removes amyloid-beta – the plaque thought to underlie Alzheimer’s disease.
Within the framework of the study period, 0.7 percent of the participants died in the treatment group and 0.8 percent in the placebo group. According to the researchers, none of the deaths could be linked to the treatment.
The company behind the drug has already submitted an application for approval to the US FDA under a so-called accelerated procedure.