Lecanemab: All about the Alzheimer's drug that shows promise

Lecanemab, an experimental Alzheimer's drug made by Eisai Co Ltd and Biogen slowed cognitive and functional decline in a large trial of patients in the early stages of the disease, reports said this week.

• Lecanemab is an antibody that targets and removes toxic clumps of a protein called amyloid beta that accumulate in the brains of Alzheimer's patients.
• The protein amyloid beta forms a plaque that researchers believe is a contributor to Alzheimer's. There are however some experts who debate this.
• Clinical trials on 1800 patients with early-stage Alzheimer's has showed that Lecanemab slows the advance of the disease.
• Patients were monitored using a scale that measures how they do in areas like memory, judgement, problem solving and personal care.
• In those with mild cognitive impairment and early-stage dementia, the drug showed a 27% reduction in cognitive decline after 18 months.
• There is a debate on whether the benefit from lecanemab is robust enough.
• Yet it already holds out two promises: a) preventing decline altogether is possible b) early intervention may possibly yield better results.
• A statement from the Alzheimer’s Association called the findings the most encouraging to date for potential treatments.
• Alzheimer’s has no known cure. Long-standing treatments on the market just manage symptoms.
• Last year, Biogen’s Aduhelm became the first new Alzheimer’s drug introduced in nearly two decades. But it has largely flopped, reports say.

Some experts called it a "positive effect" and not a huge effect. Eisai is seeking FDA approval in the US under an accelerated pathway, with a decision expected in early January.