Pharmacokinetic and pharmacodynamic measurements of edoxaban were obtained at peak and trough, which helps interpret the clinical findings.13 Moreover, the median TTR was 68.4% among patients treated with warfarin, which is higher than that reported in previous direct oral anticoagulant versus warfarin trials24–26 or in a US assessment of 138 319 Americans with AF (median TTR 57.5%).29 This evidence concerns the gene TTR and atrial fibrillation.