Background: In the ENSURE-AF study (NCT 02072434), the oral factor Xa inhibitor edoxaban showed a similar efficacy and safety profile vs enoxaparin–warfarin (enox–warf) in patients undergoing electrical cardioversion of nonvalvular atrial fibrillation.
Methods: This prespecified ancillary analysis examined the efficacy and safety of edoxaban vs enox–warf in patients who were vitamin K antagonist (VKA) naïve or experienced at the time of randomisation in the ENSURE-AF study. The primary efficacy endpoint was a composite of stroke, systemic embolic event (SEE), myocardial infarction (MI), and cardiovascular death analysed during the overall study period, 28 days on study drug after cardioversion + 30 days follow-up. The primary safety endpoint was the composite of major and clinically relevant nonmajor bleeding analysed during the on-treatment period from the time of first dose to last dose of study drug taken + 3 days.
Results: Of 2,199 patients enrolled in ENSURE-AF, 1,095 were randomised to edoxaban and 1,104 to enox–warf. Mean age was 64±10 years and 64.2±11 years, respectively. Baseline characteristics were similar for patients who were VKA naïve and experienced vs the comparative edoxaban treatment arm. There were fewer primary efficacy endpoint events with edoxaban than enox–warf in VKA experienced or naïve. There were no significant differences in bleeding rates regardless of treatment or VKA experience (Table).
Conclusion: In the ENSURE-AF study, edoxaban had comparable efficacy and safety to optimized usual anticoagulation with enox–warf. The primary efficacy endpoint outcomes were not significantly different between patients who were VKA experienced or naïve.