New Data Presented at the Clinical Trials on Alzheimer’s Disease (CTAD) Conference 2025 Confirms Pharmacological Effect of LEQEMBI® (lecanemab-irmb) on Neurotoxic Aβ Protofibrils in CSF

TOKYO and CAMBRIDGE, Mass., Dec. 02, 2025 (GLOBE NEWSWIRE) -- Eisai Co., Ltd. (Headquarters: Tokyo, CEO: Haruo Naito, “Eisai”) and Biogen Inc. (Nasdaq: BIIB, Corporate headquarters: Cambridge, Massachusetts, CEO: Christopher A. Viehbacher, “Biogen”) announced today that the latest data confirming the pharmacological effect of lecanemab (generic name, U.S. brand name: LEQEMBI®), an anti-Aβ protofibril* antibody, on Aβ protofibrils (PF) in cerebrospinal fluid (CSF) was presented at the 18th Clinical Trials on Alzheimer’s Disease (CTAD) Conference. The findings represent the results from a large-scale clinical study demonstrating, for the first time, that binding of lecanemab to PF can be measured in CSF, enabling further understanding of how lecanemab slows Alzheimer’s disease (AD) progression.