Biogen/Eisai announce latest findings for Leqembi in Alzheimer’s disease

Eisai Co (ESAIY) and Biogen Inc. (BIIB) announced that the latest findings for lecanemab-irmb, an anti-amyloid beta protofibril* antibody for the treatment of early Alzheimer’s disease, were presented at the Clinical Trials for Alzheimer’s Disease Conference, held in Madrid, Spain, and virtually. In July 2024 at the Alzheimer’s Association International Conference 2024, results from the open-label long-term extension study (OLE) following the core study of the lecanemab Phase 3 Clarity AD study were presented, showing that the mean change from baseline in CDR-SB (global cognitive and functional scale) in the lecanemab treated group relative to the placebo group was -0.45 at 18 months, and at 36 months, this expanded to -0.95 compared to a prespecified natural history** cohort of AD. There was a 30% reduction in the relative risk of progressing to the next disease stage In addition, the tau PET substudy of the lecanemab Phase 3 Clarity AD clinical study showed that with three (3) years of continuous treatment with lecanemab, 59% of patients with no or low tau accumulation in the brain (no tau/low tau) at baseline showed improvement or no decline, and 51% showed improvement from baseline on the Clinical Dementia Rating-Sum of Boxes global cognitive and functional scale. Clarity AD data presented at CTAD expand on these initial results to include additional measurements resulting from three years of continuous lecanemab treatment in patients with low levels of amyloid accumulation in the brain at baseline (less than 60 Centiloids: low amyloid). These data show that 46% of patients improved or had no decline, and 33% showed improvement from baseline on the CDR-SB. On the ADAS-Cog14 measurement scale, 46% of patients showed improvement or no decline and 43% showed improvement. On the ADCS MCI-ADL, 51% of patients showed improvement or no decline and 48% showed improvement. These results – from no tau/low tau population and low amyloid populations – suggest that earlier initiation of lecanemab treatment may have a positive impact on disease progression of early AD patients and may provide continued benefits to patients with early AD over the long term.