BRIEF—Eisai and Biogen's Leqembi IV approved in Japan

Japanese drugmaker Eisai and US partner Biogen today announced that their humanized amyloid-beta (Aβ) monoclonal antibody Leqembi Intravenous Infusion (200 mg, 500mg, lecanemab) has been approved in Japan as a treatment for slowing progression of mild cognitive impairment (MCI) and mild dementia due to Alzheimer’s disease (AD).

Japan is the second country to grant approval, following the traditional approval in the USA in July 2023.

Leqembi’s approval is based on Phase III data from Eisai’s large, global Clarity AD clinical trial, in which the drug met its primary endpoint and all key secondary endpoints with statistically significant results and confirmed the clinical benefit of Leqembi.

Eisai noted that it will conduct a post-marketing special use results survey (all-case surveillance) in all patients who are administered Leqembi until data from a certain number of patients are accumulated after market launch, in accordance with an approval condition imposed by the Ministry of Health, Labor and Welfare.

In addition, the appropriate use of Leqembi will be promoted in accordance with the package insert and training materials will be developed for healthcare professionals to assist the management and monitoring of amyloid-related imaging abnormalities (ARIA).