Abstract
Lecanemab, a monoclonal antibody targeting β-amyloid protofibrils, has shown promising results in a Phase III clinical trial for the treatment of early stages of Alzheimer's disease (AD) and has been approved by the European Medicines Agency. An Early Market Authorization could be submitted to the French regulatory agencies, potentially allowing for the drug's use in clinical practice in France in 2025. To guide French clinicians in administering lecanemab in a standardized way, the French Federation of Memory Clinics has developed appropriate use recommendations for lecanemab that highlight relevant questions established to ensure an optimal risk-benefit ratio. The recommendations emphasize that lecanemab treatment requires a comprehensive individualized evaluation of the risk-benefit ratio, which should occur in multidisciplinary meetings. When approved, the guidelines support the use of blood biomarkers, proposing specific cutoffs for patients eligible for lecanemab under restricted conditions. In addition to the European Medicines Agency restrictions in patients on anticoagulants, and APOE4 homozygotes, the guidelines recommend against lecanemab treatment for patients with high amyloid-related hemorrhagic risk such as probable cerebral amyloid angiopathy (Boston criteria v1.5) until further data become available. Additionally, we recommend that MRI monitoring be started before the third infusion to account for early Amyloid Related Imaging Abnormalities (ARIA) occurring on lecanemab. It is recommended to establish a specific clinical care pathway with protocols for patients with ARIA, with trained physicians and radiologists with expertise in neurological emergency and intensive care. Finally, a discontinuation protocol based on dementia severity assessment after 18 months of lecanemab treatment is suggested. Access to lecanemab requires a personalized biological and genetic diagnosis of AD, which is currently not necessary in most cases. Therefore, the healthcare system must rapidly adjust to new diagnostic procedures and treatment delivery to ensure equal access for all individuals.