An indirect comparison of dabigatran, rivaroxaban and apixaban for atrial fibrillation

Simon Mantha; Jack Ansell

doi:10.1160/TH12-02-0093

Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2012; 108(03): 476-484
DOI: 10.1160/TH12-02-0093

Review Article

Schattauer GmbH

An indirect comparison of dabigatran, rivaroxaban and apixaban for atrial fibrillation

Authors

Simon Mantha

¹Department of Medicine, Lahey Clinic, Burlington, Massachusetts, USA
Jack Ansell

²Department of Medicine, Lenox Hill Hospital, New York, New York, USA

Abstract

Summary

New oral anticoagulant drugs are emerging as alternatives to warfarin for the prevention of stroke in patients with non-valvular atrial fibrillation. Two agents are direct factor Xa inhibitors (rivaroxaban and apixaban), and the third is a direct thrombin inhibitor (dabigatran). They have been separately compared to warfarin in large randomised trials. Our objective was to indirectly compare the three agents to each other for major efficacy and safety outcomes. Studies were assessed for comparability and the odds ratios of selected outcomes for each anticoagulant versus one another were estimated indirectly. The three cohorts differed significantly in terms of CHADS₂ score and the number of individuals with a past history of stroke, transient ischemic attack or systemic embolism. The estimated odds ratio of stroke or systemic embolism was 1.35 for rivaroxaban vs dabigatran 150 mg (p=0.04), 0.97 for rivaroxaban versus dabigatran 110 mg (p=0.81), 1.22 for apixaban versus dabigatran 150 mg (p=0.18), 0.88 for apixaban versus dabigatran 110 mg (p=0.34) and 0.90 for apixaban versus rivaroxaban (p=0.43). The estimated odds ratio of major bleeding was 1.10 for rivaroxaban versus dabigatran 150 mg (p=0.36), 1.28 for rivaroxaban versus dabigatran 110 mg (p=0.02), 0.74 for apixaban versus dabigatran 150 mg (p=0.004), 0.87 for apixaban versus dabigatran 110 mg (p=0.17) and 0.68 for apixaban versus rivaroxaban (p<0.001). In conclusion, the available data indicate no significant difference in efficacy between dabigatran 150 mg and apixaban for the prevention of stroke or systemic embolism in patients with non-valvular atrial fibrillation. It appears however that apixaban is associated with less major bleeding than dabigatran 150 mg or rivaroxaban and that rivaroxaban is less effective than dabigatran 150 mg in preventing stroke or systemic embolism. Such an indirect comparison should be used only to generate hypotheses which need to be tested in a dedicated randomised trial comparing the three drugs directly.

Keywords

Atrial fibrillation - anticoagulants - stroke

Full Text

References

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