Japanese pharmaceutical company Eisai is set to make a groundbreaking move in the fight against Alzheimer’s disease. The company announced plans to seek U.S. regulatory approval for the preventative use of its Alzheimer’s drug, lecanemab, as early as the fiscal year beginning April 2026.
Lecanemab, marketed as Leqembi, represents a significant advancement in Alzheimer’s treatment, particularly in its early stages. The drug targets patients who show accumulation of amyloid beta—a protein linked to Alzheimer’s—yet have not developed dementia symptoms. Its preventive application could dramatically reduce healthcare costs associated with medical and nursing care for Alzheimer’s patients.
Developed in collaboration with U.S.-based Biogen, lecanemab has already been approved in the U.S. and Japan for patients with early-stage Alzheimer’s and mild dementia. Eisai is in the final stages of clinical trials to ascertain the drug’s effectiveness and safety for preventative use. The company’s plan to apply for an expanded use in the U.S. from 2026 hinges on these trial outcomes.
The potential market for lecanemab as a preventive treatment is vast. Alzheimer’s Disease International estimates around 50 million people worldwide suffer from dementia, with 60% to 70% of these cases being Alzheimer’s. Eisai CEO Haruo Naito highlighted the immense scope, citing an estimated 315 million people globally in the preclinical stage of Alzheimer’s.
In the U.S., lecanemab may receive coverage under private medical insurance. Eisai’s strategy includes monitoring the U.S. approval process before pursuing expanded use in Japan, where preventative treatments typically don’t fall under insurance coverage. This strategic approach underscores the company’s commitment to addressing a critical global health challenge and marks a significant milestone in Alzheimer’s research and treatment.
