Eisai Co., Ltd. and Biogen Japan Ltd. have announced that Eisai has entered into a research collaboration agreement with the National Center of Neurology and Psychiatry to conduct apolipoprotein E (APOE) genetic testing in the dementia research and development program, “Development and Analysis of a National Clinical Registry of Disease-Modifying Therapies for Alzheimer’s Disease” (“AD-DMT Registry”). The research will be implemented by the Japan Agency forMedical Research and Development (AMED), with NCNP as the lead research institution.

The APOE gene is known to be a risk factor for the onset of Alzheimer’s disease and is also associated with the frequency of amyloid-related imaging abnormalities (ARIA) in anti-amyloid β antibody treatments such as lecanemab (LEQEMBI®).

In Japan, at present, APOE genetic testing is not available for routine clinical practice under National Health Insurance. For this reason, by using APOE genetic information collected in the AD-DMT Registry, Eisai and NCNP can further study the relationship between the APOE genotype and the safety and efficacy of treatment with lecanemab.

Based on this research collaboration agreement with NCNP, Eisai will cover the cost of the APOE genetic testing conducted in the AD-DMT Registry. The findings, along with data collected from the lecanemab-specific post-marketing surveillance (all-casesurveillance), will be part of the reexamination of lecanemab’s application by the Japanese Pharmaceuticals and MedicalDevices Agency (PMDA) to ensure the label reflects the latest scientific understanding with the goal of improving patientoutcomes.

Eisai and Biogen Japan will continue to contribute to the advancement of Alzheimer’s disease treatment through ongoing collaboration with academia. In Japan, Eisai and Biogen Japan will co-promote lecanemab, with Eisai distributing the product as the Marketing Authorization Holder.