TOKYO and CAMBRIDGE, Mass., July 30, 2025 /PRNewswire/ -- Eisai Co., Ltd. (Headquarters: Tokyo, CEO: Haruo Naito, "Eisai") and Biogen Inc. (NASDAQ:BIIB, Corporate headquarters: Cambridge, Massachusetts, CEO: Christopher A. Viehbacher, "Biogen"), Corporate headquarters: Cambridge, Massachusetts, CEO: Christopher A. Viehbacher, ", Biogen", ) announced today that the two-year real-world study in the U.S. of lecanemab (generic name, product name: LEQEMBI®), an anti-Aβ protofibril* antibody, was presented at the Alzheimer's Association International Conference (AAIC) 2025, held in Toronto, Canada and virtually. Only lecanemab fights AD in two ways – targeting both amyloid plaque and protofibrils*