Alzheimer’s drug data shows results but also risks

TOKYO—Experts hailed full data Wednesday showing a new drug can slow cognitive decline in Alzheimer’s patients, but warned improvements were comparatively small and the treatment can have serious side effects like brain bleeds and swelling. Preliminary data from a trial of lecanemab was released in September and found it slowed cognitive decline by 27 percent across an 18-month period. The results showed 17.3 percent of patients administered the drug experienced brain bleeds, compared with 9 percent of those receiving a placebo. And 12.6 percent of those taking the drug experienced brain swelling, compared with just 1.7 percent of those in the placebo group. Deaths were reported at approximately the same rate in both arms of the trial of the drug developed by Biogen and Eisai. The results were welcomed by researchers, including Bart De Strooper, director of the UK Dementia Research Institute. “This is the first drug that provides a real treatment option for people with Alzheimer’s,” he said. “While the clinical benefits appear somewhat limited, it can be expected that they will become more apparent if the drug is administered over a longer time period.”