FDA to Consider the Approval of a Subcutaneous Starting Dose for Lecanemab

The Food and Drug Administration (FDA) has accepted a Supplemental Biologics License Application (sBLA) for Leqembi IQLIK (lecanemab-irmb; Eisai, Tokyo, Japan; Biogen, Cambridge, MA) for review as a once-weekly, subcutaneously administered starting dose for the treatment of people with early Alzheimer disease (AD). The sBLA has been granted Priority Review, with a Prescription Drug User Fee Act (PDUFA) action date of May 24, 2026. In August 2025, the FDA approved subcutaneous Leqembi IQLIK for maintenance dosing for people with early AD who have already completed a starting dose of 18 months of intravenous (IV) therapy. If the new sBLA is approved, people with early AD would have a subcutaneous alternative to the currently available biweekly IV starting regimen.

The sBLA seeks approval of a 500 mg weekly subcutaneous starting dose administered via autoinjector, delivered as 2 injections of 250 mg. The autoinjector delivers each injection in approximately 15 seconds. According to a statement from Eisai and Biogen, the approval of the subcutaneously administered Leqembi IQLIK as a starting dose would provide patients with the option to initiate and continue treatment at home using the autoinjector, which eases the healthcare burden of infusion preparation and nurse monitoring.  

In the phase 3 CLARITY AD (NCT03887455) study and its open-label extension, weekly 500 mg subcutaneous dosing with Leqembi IQLIK achieved plasma exposure comparable to biweekly IV administration, with similar clinical and biomarker outcomes. The safety profile of subcutaneous administration was consistent with IV dosing, with systemic injection- or infusion-related reactions reported in fewer than 2% of participants.

The prescribing information for Leqembi IQLIK includes a Boxed Warning for amyloid-related imaging abnormalities.

Source: Eisai Inc. FDA accepts Leqembi IQLIKTM (lecanemab-irmb) supplemental biologics license application as a subcutaneous starting dose for the treatment of early Alzheimer’s disease under priority review. PR Newswire. Published 25 January, 2026. Accessed 26 January, 2026. https://prnmedia.prnewswire.com/news-releases/fda-accepts-leqembi-iqliktm-lecanemab-irmb-supplemental-biologics-license-application-as-a-subcutaneous-starting-dose-for-the-treatment-of-early-alzheimers-disease-under-priority-review-302669609.html