Washington University's Memory Diagnostic Center treated 234 early Alzheimer's patients with lecanemab over 14 months, providing the first large real-world safety dataset outside clinical trials. Infusion-related reactions occurred in 37% of patients but were typically mild. Amyloid-related imaging abnormalities (ARIA) developed in 22% of monitored patients, with symptomatic ARIA in 5.7% and clinically severe ARIA in only 1%. Patients with mild dementia had significantly higher symptomatic ARIA rates (27%) than those with MCI or very mild dementia (1.8%). No deaths or macrohemorrhages occurred. Only 4.3% withdrew due to ARIA. These findings suggest lecanemab can be safely administered in well-resourced specialty memory clinics, though the higher ARIA risk in mild dementia patients warrants careful patient selection and monitoring protocols.
