Initial Real-World Evidence for Lecanemab in the United States

Abstract

Background: Lecanemab is the first anti-amyloid monoclonal antibody with full approval in the US for the treatment of early Alzheimer’s disease (AD). This observational study aimed to provide information about patient demographics, clinical characteristics, provider specialty, and lecanemab utilization patterns. Methods: This observational study used open administrative claims from the PurpleLab, a database encompassing medical and pharmacy claims derived from diverse sources, such as clearinghouses and Pharmacies. We included patients receiving one or more lecanemab doses between January 6, 2023 and October 31, 2024, and having continuous clinical activity ≥ 6 months prior to the first lecanemab infusion. The observation period ran from the first lecanemab infusion to the latest clinical activity or data availability. Treatment gaps were calculated as the number of gap days in lecanemab supply between consecutive infusions. Results: Among the study population (n = 4261), mean age was 75.2 years, 77.8% were White, 98.4% lived in urban settings, 81.7% were treated by neurologists, 77.3% had AD, and 31.7% had mild cognitive impairment. Mean follow-up period was 171.1 days. Lecanemab infusions averaged 1.9 per patient per month (SD 1.0), 16.3 days apart (SD 11.0), and 2.8% of patients experienced a treatment interruption ≥90 days. Conclusions: Lecanemab utilization followed US FDA-approved prescribing information. Disparities for minority and rural-based populations were observed suggesting opportunities to improve access for underserved populations.