Subcutaneous Leqembi Under Review by FDA

The Food and Drug Administration (FDA) has accepted the Biologics License Application (BLA) for Leqembi (lecanemab-irmb; Eisai, Tokyo, Japan; Biogen, Cambridge, MA) subcutaneous (SC) autoinjector for weekly maintenance dosing to treat individuals with early Alzheimer disease (AD). The FDA has set a Prescription Drug User Fee Act (PDUFA) action date of August 31, 2025, and if the BLA is approved, treatment using the Leqembi SC autoinjector will be permitted in the United States.

Positive data from the phase 3 Clarity AD open-label extension (OLE) study form the basis of the BLA. The study results, which were published in The New England Journal of Medicine, demonstrate that weekly SC dosing with Leqembi removed 14% more amyloid plaque than biweekly intravenous (IV) treatment. The findings suggest that the biomarker and clinical benefits of IV Leqembi treatment may persist with weekly SC treatment, with a potential for continued benefit even after the removal of amyloid plaques from the brain.

Using the SC autoinjector, Leqembi can be administered in approximately 15 seconds at 360 mg weekly, for use by patients who have already completed the biweekly IV phase of treatment. According to a statement from the company, Biogen expects that the SC autoinjector will increase the ease of Leqembi treatment and potentially reduce visits to infusion sites, the need for nursing care, and hospitalizations.