Eisai Co., Ltd. and Biogen Inc. announced that Eisai has initiated the rolling submission of a Biologics License Application (BLA) to the U.S. Food and Drug Administration (FDA) for lecanemab-irmb (U.S. brand name: LEQEMBI®) subcutaneous autoinjector for weekly maintenance dosing after it was granted Fast Track designation by the FDA. LEQEMBI is indicated for the treatment of Alzheimer's disease (AD) in patients with Mild Cognitive Impairment (MCI) or mild dementia stage of disease (collectively referred to as early AD). The BLA is based on data from the Clarity AD (Study 301) open-label extension (OLE) and modeling of observed data.

If approved by the FDA, the LEQEMBI autoinjector could be used to administer LEQEMBI at home or at medical facilities. The injection process requires less time than the IV formulation. As part of the subcutaneous autoinjector 360 mg weekly maintenance regimen under review, patients who have completed the biweekly IV initiation phase would receive weekly doses that maintain effective drug concentrations to sustain the clearance of highly toxic protofibrils which can continue to cause neuronal injury even after the amyloid-beta (Aß) plaque has been cleared from the brain.

AD is an ongoing neurotoxic process that begins before and continues after plaque deposition. Data suggest that early and continuing treatment may prolong the benefit even after plaque is cleared from the brain. This SC autoinjector is easier for patients and their care partners to use, and may reduce the need for hospital visits and nursing care compared to intravenous (IV) administration.

In addition to potentially maintaining the clinical and biomarker benefits, subcutaneous maintenance dosing may be more convenient for patients and their care partners to continue the treatment. LEQEMBI is now approved in the U.S., Japan and China, and applications have been submitted for review in the European Union, Australia, Brazil, Canada, Hong Kong, Great Britain, India, Israel, Russia, Saudi Arabia, South Korea, Taiwan, Singapore and Switzerland. Eisai submitted to the FDA a Supplemental Biologics License Application (sBLA) for monthly LEQEMBI intravenous (IV) maintenance dosing in March 2024.

Eisai serves as the lead for lecanemab's development and regulatory submissions globally with both companies co-commercializing and co-promoting the product and Eisai having final decision-making authority.