Clinical trials with new oral anticoagulants

Summary

To compare the efficacy and safety of the new oral anticoagulants (NOAC), ideally head-to-head clinical trials should be performed. Given the expense of such an undertaking, it is highly unlikely that such a comparison would be performed. Therefore, there is a need for an unbiased comparative assessment of the benefits and risks of the NOACs, based on the available trial data. Indirect or mixed treatment comparisons may be an useful tool to overcome these limitations also known as network meta-analysis (NMA).

The aim of this paper is to give an overview on published NMAs for dabigatran, rivaroxaban and apixaban, each assessed against warfarin in patients with atrial fibrillation, and against enoxaparin in patients undergoing total knee and total hip replacement surgery, in order to obtain insights into the comparability of the adopted methodological techniques.

Zusammenfassung

Um die Wirksamkeit und Verträglichkeit neuer oraler Antikoagulanzien (NOAK) zu vergleichen, müssten idealerweise direkte Vergleiche zwischen den Substanzen in klinischen Studien durchgeführt werden. Auf Grund des logistischen und finanziellen Aufwandes werden diese Projekte in absehbarer Zeit nicht durchgeführt werden. Indirekte Vergleiche, auch Netzwerkanalysen (NMA) genannt, lassen sich mit den vorliegenden Studien zwischen den NOAKs vornehmen, um die Frage der Vergleichbarkeit anzugehen. In der postoperativen Phase nach Knieund Hüftgelenkersatz und bei Patienten mit Vorhofflimmern sind derzeit diese Vergleich möglich. Indirekte Vergleiche sind jedoch auch mit Einschränkungen behaftet.

Diese Arbeit gibt eine Übersicht der aktuell vorliegenden NMAs und versucht deren unterschiedliche Ergebnisse mit der Pharmakologie der NOAKs und den methodischen Problemen von NMAs zu beleuchten.

Keywords

Oral anticoagulants - apixaban - dabigatran - rivaroxaban - atrial fibrillation - total knee replacement - total hip replacement - prophylaxis of thromboembolism

Schlüsselwörter

Antikoagulanzien - Apixaban - Dabigatran - Rivaroxaban - Vorhofflimmern - postoperative Thromboembolieprophylaxe

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