Abstract
INTRODUCTION: We investigated real-world efficacy, safety, and plasma biomarker dynamics of Lecanemab in Chinese patients with Alzheimer's disease (AD). METHODS: A multi-center prospective cohort study enrolled 68 AD patients. Cognitive scales and plasma biomarkers were assessed at baseline (V0), 2.5 months (V1), and 7 months (V2). RESULTS: Alzheimer's Disease Assessment Scale-Cognitive Subscale 14-item version (ADAS-cog14) scores improved significantly at both follow-ups, and plasma p-tau181 consistently declined. Both p-tau181 and p-tau217 correlated with cognition and partially predicted treatment response (area under the curve [AUC] = 0.734 and 0.713). Mixed-effects modeling confirmed their dynamic association with ADAS-cog14 scores. Subgroup analyses indicated benefits across sex and apolipoprotein E4 status, while moderate-to-severe cases showed limited response. Lecanemab was well tolerated, with asymptomatic amyloid-related imaging abnormalities in 17.65% and mild infusion reactions in 5.88%. DISCUSSION: These findings support the short-term efficacy and safety of Lecanemab in early AD and highlight plasma biomarkers as a treatment-responsive biomarker. HIGHLIGHTS: Lecanemab improved cognitive function in Chinese patients with mild cognitive impairment due to Alzheimer's disease (AD-MCI) and mild AD over a short period. Plasma p-tau181 and p-tau217 showed significant correlation with cognitive scores, and their baseline level could partially predict the efficacy of lecanemab. Lecanemab showed a favorable safety profile with low, manageable rates of amyloid-related imaging abnormalities (ARIA) and infusion reactions.