[Disease-modifying Drugs in Alzheimer's Disease: Indications and Efficacy Evaluation].

The launch of lecanemab (an anti-Aβ antibody) has introduced a new treatment for Alzheimer's disease. In contrast to conventional therapeutic approaches to dementia, this drug requires new concepts in diagnosis, evaluation, and adverse effects. Specifically, evaluation of the efficacy of lecanemab is extremely important because this drug does not prevent but only slows the rate of disease progression. In this report, I have discussed future issues, including my personal viewpoint and also described the guidelines for promotion of the optimal use of lecanemab issued by the Ministry of Health, Labour, and Welfare.