Dabigatran 150 mg more effective than warfarin for stroke prevention in AF
14 April 2011
MedWire News: Findings from two subanalyses of the RE-LY study indicate that dabigatran 150 mg is more effective than warfarin at reducing the risk for stroke in patients with atrial fibrillation (AF).
Both analyses, presented at the American College of Cardiology Annual Scientific Sessions in New Orleans, Louisiana, USA, confirmed results from the main RE-LY (Randomized Evaluation of Long-Term Anticoagulation Therapy) trial, which showed that at a dose of 110 mg dabigatran has similar efficacy to warfarin, but has higher efficacy at 150 mg.
In the first analysis, Jonas Oldgren (Uppsala Clincal Research Center, Sweden) and team looked specifically at the effect of the CHA2DS2-VAsc stroke risk score on the outcomes of 18,113 AF patients receiving dabigatran 110 mg (D110), dabigatran 150 mg (D150), or warfarin.
The CHA2DS2-VAsc score predicts stroke risk in AF patients by assigning a score of 1 point for the presence of heart failure, hypertension, age 65–74 years, diabetes, female gender, or vascular disease, and a score of 2 points for a history of stroke or TIA and an age of 75 years or older.
The researchers found that both doses of dabigatran were superior to warfarin at reducing stroke risk in patients with CHA2DS2-VAsc scores of 2 or less (n=4042). However, among patients with scores of 3 or more, only D150 was superior while D110 was non-inferior to warfarin at preventing stroke.
The second analysis involved 18,107 patients with permanent (n=6375), paroxysmal (n=5943), or persistent (n=5789) AF, and was designed to determine the efficacy of dabigatran in patients with different types of AF.
Led by Greg Flaker (McMaster University, Hamilton, Ontario, Canada), the team found that, irrespective of AF type, D150 was more effective than warfarin at preventing stoke, and D110 was equally as effective as warfarin.
Specifically, compared with warfarin treatment, the risk for stroke among patients taking D150 was significantly reduced by 30%, 39%, and 36% for persistent, paroxysmal, and permanent AF, respectively.
But among D110 patients there was no significant difference in stroke risk compared with warfarin treatment.
In addition, no significant difference was observed in the risk for major bleeding episodes, which occurred at an approximate rate of 3% among all patients, irrespective of AF type and treatment.
Flaker and team therefore conclude that dabigatran is as safe as and more effective than standard warfarin treatment at preventing stroke in AF patients.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
American College of Cardiology 60th Annual Scientific Sessions; New Orleans, Louisiana, USA: 2–5 April 2011
© Copyright Springer Healthcare Ltd, 2011
