Lecanemab's Path Forward: Navigating the Future of Alzheimer's Treatment in Europe Amidst the EMA's Rejection

Lecanemab (Leqembi^©, Biogen), a humanized anti-amyloid-beta monoclonal antibody, has been approved for early-stage Alzheimer's disease (AD) in several countries, including the US and Japan. However, the European Medicines Agency (EMA) recently issued a negative opinion on its marketing authorization, reflecting concerns over the clinical value and manageability of anti-amyloid treatments. This decision highlights the ongoing disconnect between research advancements and clinical practice, where the focus on biological markers over tangible clinical improvements remains contentious. Despite promising biological effects, lecanemab's clinical outcomes have been modest, raising questions about its therapeutic role. The EMA's refusal underscores the need to address doubts surrounding the real-world effectiveness and safety of such treatments, especially concerning amyloid-related imaging abnormalities (ARIAs), a common side effect observed in clinical trials. The recent approval of lecanemab by the UK's Medicines and Healthcare products Regulatory Agency, despite the National Institute for Health and Care Excellence's rejection on cost-effectiveness grounds, further fuels the debate on the feasibility of anti-amyloid therapies. This commentary emphasizes the importance of real-world data on lecanemab's impact on cognitive decline, daily functioning, and side-effect management. As the global clinical use of lecanemab increases, continuous and standardized reporting on its outcomes is crucial for guiding future regulatory decisions and for potentially bridging the gap between research and practice in AD treatment.