Core Insights - BioArctic AB's partner Eisai presented significant findings on lecanemab (Leqembi®) at the Alzheimer's Association International Conference, highlighting its clinical efficacy and safety profile over four years of treatment [1] Group 1: Clinical Efficacy - Four years of lecanemab treatment helped patients remain in the early stage of Alzheimer's disease longer compared to the natural disease course, with a 27% slowing of clinical decline as measured by the CDR-SB scale [2] - Among patients who completed the core study, 95% chose to continue in the open-label extension study, demonstrating a 1.01-point less decline over three years and a 1.75-point less decline after four years compared to expected decline in other cohorts [3] - In a tau PET sub-study, 69% of participants with low tau levels showed improvement or no decline after four years of treatment, indicating sustained long-term benefits [4] Group 2: Safety Profile - No new safety findings were observed in the open-label extension study, with rates of amyloid-related imaging abnormalities (ARIA) decreasing after the first 12 months and remaining consistent throughout four years [5] - Interim real-world data indicated that 84% of patients on lecanemab either remained stable or clinically improved, with a safety profile consistent with phase 3 data [6] Group 3: Treatment Administration - Subcutaneous dosing of lecanemab is being explored as a new treatment option, with a weekly maintenance dose of 360 mg showing comparable clinical and biomarker benefits to intravenous administration [9][10] - The safety profile of the 360 mg weekly subcutaneous maintenance dose was consistent with intravenous therapy, with systemic injection reactions occurring in less than 1% of patients [11] - Subcutaneous dosing allows for easier home administration, potentially reducing the need for infusion center visits and enhancing patient compliance [12] Group 4: Commercialization and Collaboration - Eisai leads the global development and regulatory submissions for Leqembi, with BioArctic holding rights for commercialization in the Nordic region [13][17] - BioArctic has no development costs for lecanemab and is entitled to payments related to regulatory approvals and sales milestones [17] - The collaboration between BioArctic and Eisai has been ongoing since 2005, focusing on the development and commercialization of Alzheimer's disease treatments [16]