Baseline epidemiological differences between donanemab and lecanemab users in real-world settings: a retrospective cohort study.

Abstract

Aims: Donanemab and Lecanemab are anti-amyloid monoclonal antibodies recently approved for the treatment of Alzheimer's disease. Although their efficacy and safety have been investigated in randomized trials, real-world epidemiological data on treated populations remain limited. This study aimed to compare baseline clinical and laboratory characteristics of patients treated with donanemab versus lecanemab in routine practice.

Patients and methods: We conducted a retrospective analysis using the TriNetX US Collaborative Network, including patients with Alzheimer's disease treated with donanemab or lecanemab between January 2024 and September 2025. Demographics, laboratory values, comorbidities, and concomitant medications were compared using standardized mean differences (SMD) and p-values. Variables with SMD ≥0.1 or p < 0.05 were considered meaningfully different.

Results: A total of 1,799 patients were included (donanemab n = 360; lecanemab n = 1,439). Demographic characteristics were well balanced (mean age 73.1 vs 72.5 years; SMD 0.028). Lecanemab users were more likely to be prescribed antidepressants (52% vs 41%; p < 0.0001; SMD = 0.23) and donepezil (61% vs 52%; p = 0.0145; SMD = 0.14). Donanemab users had higher prothrombin time (12.2 ± 2.17 vs 11.8 ± 1.66 s; p = 0.0158; SMD = 0.20) and INR (1.06 ± 0.19 vs 1.03 ± 0.13; p = 0.0369; SMD = 0.17), and a higher prevalence of vascular dementia (81% vs 76%; p = 0.0272; SMD = 0.12).

Conclusion: While demographic variables were similar. These findings likely reflect real-world clinical selection patterns and should be accounted for in comparative effectiveness and safety analyses of anti-amyloid therapies.