BioArctic's partner Eisai presents new Leqembi data supporting subcutaneous autoinjector

BioArctic AB's partner Eisai presented new data on July 13, 2026, at the Alzheimer's Association International Conference (AAIC) in London. The findings indicate that the Leqembi (lecanemab) subcutaneous autoinjector (SC-AI) formulation offers efficacy and safety comparable to intravenous (IV) administration in patients with early Alzheimer's disease.

Key findings revealed that a once-weekly 500 mg SC-AI dose achieved similar drug exposure levels in the body as the therapeutic IV regimen (10 mg/kg every two weeks). This supports the expectation of comparable clinical efficacy and safety, regardless of the administration route. The subcutaneous option may provide a convenient at-home alternative to IV infusions, potentially improving treatment access and enabling more flexible care delivery across healthcare settings.

The data suggest that the drug's efficacy and safety are driven by exposure rather than the route of administration. The study also indicated that treatment can be switched between IV and SC administration as needed. If a dose is missed, it can be administered the following day or up to six days later, offering increased flexibility.

The safety profile of subcutaneous Leqembi was generally consistent with the IV formulation. The incidence of ARIA-E, a type of brain-related side effect, was predicted to be similar for both administration methods. Local injection site reactions were observed with the subcutaneous form, while systemic reactions were less frequent. The incidence of anti-drug antibodies was low, and no neutralizing antibodies were detected.

Furthermore, data from two US treatment centers provided early insights into the clinical use and real-world outcomes of the SC-AI formulation. Patients and care partners at these centers reported high satisfaction with subcutaneous Leqembi, appreciating its convenience and expressing a high willingness to recommend it.