Alzheimer’s drug slows cognitive decline

Eisai and Biogen’s experimental Alzheimer’s disease medicine slows cognitive decline in a rigorously monitored trial, but it may pose a risk of dangerous side effects for certain patients, according to the recent results presented.

Lecanemab was linked to a sort of brain enlargement in 12.6% of trial subjects, a side effect previously observed with comparable medications. In a follow-up study, fourteen per cent of patients developed microhemorrhages in the brain, a symptom connected to two recent fatalities of Lecanemab recipients, and five patients had macrohemorrhages.

In September, the firms reported that the 18-month trial, which involved over 1,800 patients with early-stage Alzheimer’s, found that therapy with Lecanemab lowered the rate of decline on a clinical dementia scale (CDR-SB) by 27% compared to placebo.

“All of these amyloid-lowering drugs carry a risk for an increased brain haemorrhage,” said Dr Ronald Petersen of the Mayo Clinic in Rochester, Minnesota. “I think the primary outcomes, the secondary outcomes, the amyloid-lowering is pretty impressive.”

The Alzheimer’s Association stated that the evidence showed the treatment “may significantly alter the course of the disease for those in the initial stages of Alzheimer’s disease” and urged US regulators to grant the company’s application for speedy approval.

Wednesday morning in Tokyo, Eisai shares gained 3%, while Biogen shares gained 0.9% in after-hours trading. They have increased by approximately 60% and 47%, respectively after the initial trial results were released in late September.