The FDA has approved a new starting dosage regimen for the subcutaneous formulation of Leqembi (lecanemab‑irmb), allowing adult patients with Alzheimer’s disease to initiate treatment at home with injections administered by themselves or a caregiver. The approval, granted to Eisai Inc., marks the first time an Alzheimer’s disease treatment can be started outside an infusion center using a subcutaneous regimen instead of intravenous administration.
Leqembi is an amyloid beta‑directed antibody indicated for patients with confirmed amyloid pathology and mild cognitive impairment or mild dementia due to Alzheimer’s disease. Its clinical effectiveness was established in two large randomized, placebo‑controlled trials in which patients received 10 mg/kg intravenously every two weeks over 18 months, showing reductions in amyloid plaques and clinical benefit. The newly approved subcutaneous starting regimen is supported by pharmacokinetic and imaging data demonstrating that the under‑the‑skin formulation produces comparable drug exposure and similar amyloid plaque reduction to the intravenous form.
Safety considerations remain significant. Common adverse effects include headache, infusion‑related reactions, and amyloid‑related imaging abnormalities (ARIA), which can present as brain swelling or microhemorrhages and, in rare cases, serious or life‑threatening edema or intracerebral hemorrhage. The prescribing information carries a boxed warning about ARIA and recommends ApoE ε4 genotyping prior to treatment, as homozygous carriers have higher ARIA risk. Injection‑site reactions and increased risk of intracerebral hemorrhage in patients on anticoagulants are also noted, and Leqembi is contraindicated in patients with serious hypersensitivity to lecanemab‑irmb.
Subscribe to our e-Newsletters
Stay up to date with the latest news, articles, and events. Plus, get special offers
from American Pharmaceutical Review – all delivered right to your inbox!
Sign up now!