Real-world implementation of lecanemab and donanemab in an Italian memory center: a 1-year experience

Background: Anti-amyloid monoclonal antibodies are entering clinical practice for early symptomatic Alzheimer’s disease (AD), but European real-world data on feasibility, safety, and biomarker monitoring remain limited. We report the first year of implementation of lecanemab and donanemab in an Italian tertiary memory center. Methods: We conducted a prospective observational real-world cohort study at the Center for Alzheimer’s and Related Diseases of IRCCS Ospedale San Raffaele (Milan, Italy). Twenty-nine treatment courses were administered in patients with early symptomatic AD (lecanemab, n = 9; donanemab, n = 20) under European Medicines Agency–aligned safety monitoring and risk-mitigation protocols. Given the unbalanced treatment groups, results are descriptive and not intended for direct comparison between treatments. Safety surveillance included serial magnetic resonance imaging for amyloid-related imaging abnormalities (ARIA) and systematic recording of infusion-related reactions. Biological monitoring included amyloid positron emission tomography with Centiloid quantification and plasma biomarkers (phosphorylated tau 181 and 217, glial fibrillary acidic protein, neurofilament light chain, and amyloid-β 42/40 ratio) at baseline and follow-up. Baseline comparisons and longitudinal changes were assessed using appropriate parametric or nonparametric statistical methods. Results: ARIA were infrequent. In donanemab-treated patients, mildly symptomatic ARIA-E occurred in 10% (2/20) and asymptomatic ARIA-H in 15% (3/20). In lecanemab-treated patients, asymptomatic ARIA-H occurred in 11% (1/9). Infusion-related reactions occurred in 21% (6/29) of treatment courses and were manageable with standardized premedication. Among 11 patients with six-month follow-up, amyloid burden decreased significantly (mean change − 52.4 Centiloids), and 75% of donanemab-treated patients (6/8) and 0% of lecanemab-treated patients reached amyloid positron emission tomography negativity (< 11CL). Plasma phosphorylated tau 181 and glial fibrillary acidic protein showed directional declines, consistent with expected biomarker trajectories under anti-amyloid therapy, while cognitive measures showed no significant change. Conclusions: In a structured multidisciplinary framework, lecanemab and donanemab were feasibly implemented with a preliminary favorable early safety profile, substantial amyloid reduction, and measurable plasma biomarker changes in routine practice. This experience supports the feasibility of structured real-world pathways for deployment and monitoring of disease-modifying therapies in European memory clinics, within the limitations of a small cohort and short follow-up.