Japanese pharmaceutical company Eisai Co Ltd (TYO:4523) and its Swedish partner BioArctic AB (STO:BIOA-B) announced on Tuesday that Eisai has commenced the rolling submission of the Supplemental Biologics License Application (sBLA) to the US Food and Drug Administration (FDA) for lecanemab-irmb (US brand name: LEQEMBI) subcutaneous autoinjector (SC-AI), LEQEMBI IQLIK, as a weekly starting dose after the FDA granted Fast Track Status.

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 FDA approved Eisai's Biologics License Application (BLA) for subcutaneous maintenance dosing with LEQEMBI IQLIK in August 2025.

The sBLA is based on evaluation of subcutaneous (SC) lecanemab administration across a range of doses and as part of sub-studies within the Phase 3 Clarity AD open-label extension, following the 18-month core study in individuals with early AD. If the FDA approves the LEQEMBI IQLIK 500 mg SC dosing regimen (two 250 mg injections), the autoinjector could be used to administer a once weekly starting dose, as an alternative to bi-weekly (every two weeks) intravenous (IV) dosing. This would expand the option for patients and care partners to receive LEQEMBI treatment from initiation to maintenance at home, offering a choice between IV and SC administration.

LEQEMBI is currently approved in 48 countries and is under regulatory review in 10 countries.

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