Efficacy and safety of dabigatran versus warfarin from the RE-LY trial

Current data for atrial fibrillation (AF) and stroke are predominantly derived from North American and European patients. Although the burden of AF is high in Latin America (LA), little is known about current management of AF in the region.

We aimed to assess the consistency of efficacy and safety outcomes associated with dabigatran etexilate (DE) versus warfarin in patients with AF in LA from the RE-LY (Randomised Evaluation of Long-Term Anticoagulant Therapy) trial. Data from 956 LA patients and 17 157 non-LA patients were included in this analysis. χ² test and Cox proportional regression analysis were performed. The primary efficacy outcome included all strokes or systemic embolism (SE). Main safety outcome was major bleeding.

LA patients were more often female, had higher proportion of permanent AF and lower creatinine clearance, among other characteristics. Vitamin K antagonist use at randomisation and time in therapeutic range were lower in LA than in non-LA patients (44% vs 63%, p<0.001; and 61.3±22.6% vs 64.6±19.6%, p=0.015, respectively). Efficacy endpoints were 0.91% versus 1.68% for DE 150 mg twice daily versus warfarin, respectively. Stroke/SE risk was lower in LA patients treated with DE 150 mg twice daily compared with warfarin, although not significant (HR 0.54; 95% CI 0.18 to 1.62). The annual stroke/SE rates for DE 110 mg twice daily versus warfarin were 1.82 versus 1.68, also not significantly different (HR 1.09; CI 0.44 to 2.67). There were no treatment-by-region interactions for either dose of DE on efficacy and safety outcomes.

Despite differences in the clinical profile and AF management, the efficacy and safety benefits of dabigatran over warfarin in LA patients relative to non-LA patients are consistent with those observed in the main RE-LY trial.