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# Eisai sBLA for Monthly Alzheimer’s Maintenance
- URL: https://www.fdaweb.com/eisai-sbla-for-monthly-alzheimers-maintenance/
- Published: 2024-04-01T12:00:00.000Z
- Updated: 2026-09-14T14:27:01.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5156675

Eisai has submitted a supplemental BLA for monthly Leqembi (lecanemab-irmb) intravenous maintenance dosing in Alzheimer’s disease (AD) patients with mild cognitive impairment or mild dementia stage of disease (early AD). The submission is based on modeling of observed data from the Phase 2 study (Study 201) and its open-label extension (OLE), as well as Clarity AD study (Study 301) and its OLE study, the company says.

Eisai says it was planning to submit a BLA for weekly maintenance therapy using subcutaneous (SC) administration in March but FDA told the company that an additional three months of immunogenicity data at the proposed maintenance dose of 360 mg weekly is required. Because of this, Eisai planned to initiate a rolling BLA for lecanemab SC last month under its existing fast track and breakthrough therapy designations. “However, Eisai was recently informed by the FDA that a fast-track designation specific for the SC formulation is needed to receive rolling review,” it says. “Following the guidance, Eisai submitted a request for fast track designation for the SC formulation and will initiate a rolling submission should the FDA grant this designation.”

In 7/2023, FDA converted Leqembi from accelerated approval to full approval. The drug originally received accelerated approval 1/2023\. FDA [says](https://www.fda.gov/news-events/press-announcements/fda-converts-novel-alzheimers-disease-treatment-traditional-approval?ref=fdaweb.com) it was converted to traditional approval following a determination that a confirmatory trial verified clinical benefit, making it the first drug in its class to be converted to full approval. The drug works by reducing amyloid plaques that form in the brain.