Post-marketing safety of lecanemab: a real-world study based on FAERS database, multicenter cohort and network pharmacology.

Introduction: Lecanemab is a monoclonal antibody targeting amyloid-beta (Aβ) approved for treating Alzheimer's disease (AD) with mild cognitive impairment or mild dementia. Continuous monitoring of its real-world safety profile remains essential. This study aimed to analyze lecanemab-related adverse events (AEs) using the FDA Adverse Event Reporting System (FAERS) database and a multicenter cohort, and explored mechanisms via network pharmacology. Methods: We conducted an updated disproportionality analysis of FAERS data from 2023 to 2024 to identify disproportionate reporting signals (SDRs). A multicenter retrospective cohort study was performed, including lecanemab users from June 2024 to February 2025. Data were collected from electronic medical records of five tertiary hospitals. AEs were identified and influencing factors of AE occurrence were analyzed. Additionally, a drug-gene interaction network was constructed to explore potential mechanisms. Results: In the FAERS analysis of 2,764 AEs from 1,389 lecanemab users, 12 of 41 positive SDRs were prioritized, with 75% (9/12) being nervous system disorders, primarily amyloid-related imaging abnormalities (ARIA). In the cohort study, 29.05% (43/148) of patients experienced AEs, with infusion-related reactions being most common. Age was identified as a risk factor for AE occurrence [OR (95% CI): 1.109 (1.011-1.215), P = 0.028], while pre-treatment significantly reduced AE incidence. Gene enrichment analysis suggested potential links between lecanemab-related genes and AEs. Discussion: This study provides real-world evidence on the risk profile of lecanemab, highlighting the importance of continued safety monitoring. These findings may inform discussions about the risks associated with anti-amyloid treatments and warrant further confirmation in large-scale prospective studies.