08:24 AM EST, 11/25/2025 (MT Newswires) -- Biogen (BIIB) and Eisai said Tuesday Eisai has completed the rolling submission of a supplemental Biologics License Application to the US Food and Drug Administration seeking approval for a weekly subcutaneous starting dose of lecanemab-irmb.

The companies said the treatment is approved for Alzheimer's patients in the mild cognitive impairment or mild dementia stages. Esai serves as the lead for lecanemab development, while Esai and Biogen co-promote and co-commercialize the product.

Once the FDA accepts the application, it will set a review date, they added.

The drugmakers said the filing includes data from studies evaluating various doses, as well as sub-studies within the phase 3 open-label extension study.

If approved, the drug's 500 mg regimen - given as two 250 mg autoinjector shots - would allow patients to start treatment through once-weekly injections at home instead of bi-weekly IV infusions, the company said.