PR Newswire·Nov 13, 2026, 2:16 AM ET

Leqembi® Pen subcutaneous treatment launched in Japan

Eisai launched Leqembi Pen, the subcutaneous formulation of lecanemab, in Japan on November 13, 2026, marking the second country after the US to introduce this treatment for early Alzheimer's disease.
The product received approval in Japan on September 16, 2026, & was subsequently added to the National Health Insurance (NHI) Drug Price List.
Leqembi Pen is the first & only anti-amyloid treatment in Japan enabling at-home administration via an autoinjector.
The approved regimen consists of a 500 mg dose once weekly, delivered through two pens, offering an alternative to the bi-weekly intravenous (IV) administration at medical facilities.
At-home use allows for self-administration by patients or care partners under physician guidance after training, potentially reducing clinic visits & healthcare resource usage.
MRI monitoring for amyloid-related imaging abnormalities (ARIA) remains mandatory prior to treatment initiation & at specified intervals, consistent with IV protocols.
BioArctic AB collaborates with Eisai on lecanemab development & commercialization, holding rights to commercialize the drug in the Nordic region & receiving milestone payments & royalties on global sales.
Leqembi is currently approved in 53 countries, with subcutaneous initiation treatment approved in China & Japan in September 2026, & regulatory reviews ongoing in four additional countries.