RE-LY study: Dabigatran etexilate shows greater reductions in stroke compared to warfarin

Data presented today at the 59^th Annual Scientific Session of the American College of Cardiology have shown greater reductions in stroke in patients with atrial fibrillation (AF) for dabigatran etexilate compared to the current standard of care, warfarin, irrespective of a patient’s risk profile for stroke. The new sub-group analysis from the landmark RE-LY^® study assessed the rate of stroke and systemic embolism in patients defined as being at low>2.

“For healthcare professionals treating patients with atrial fibrillation at risk of stroke and systemic embolism, this sub-group analysis is very encouraging as it shows that dabigatran etexilate 150mg bid is the first treatment reducing strokes more than warfarin across the full spectrum of stroke risk in patients with AF.”

The RE-LY^® sub-group analysis showed that dabigatran etexilate 150mg bid reduced the rate of stroke and systemic embolism compared with well-controlled warfarin, irrespective of a patient’s stroke risk. Dabigatran etexilate 110mg bid resulted in similar reductions as well-controlled warfarin. Both doses were associated with lower major bleeding rates in patients at low risk of stroke.

In detail, the results showed:

• Dabigatran etexilate 150mg bid reduced the rate of stroke and systemic embolism when compared with well-controlled warfarin across all stroke risk groups with the relative risk (RR) being 0.62 (0.38−1.02) in low, 0.61 (0.40−0.92) in moderate, and 0.70 (0.52−0.95) in high risk patients
• Dabigatran etexilate 110mg bid showed similar reductions in the rate of stroke and systemic embolism to well-controlled warfarin, with RR being 1.00 (0.65−1.55) in low, 1.04 (0.73−1.49) in moderate and 0.79 (0.59−1.06) in high risk patients
• Both doses of dabigatran etexilate were associated with lower rates of major bleeding compared to well-controlled warfarin in low risk patients (D110mg RR: 0.67 (0.49−0.90), D150mg RR: 0.73 (0.54−0.98)).
• Consistent with the overall RE-LY^® results both doses of dabigatran were associated with substantial reductions in the rates of intracranial haemorrhage in all risk groups.

Lead author Dr Jonas Oldgren, Uppsala University Hospital, Sweden said, “For healthcare professionals treating patients with atrial fibrillation at risk of stroke and systemic embolism, this sub-group analysis is very encouraging as it shows that dabigatran etexilate 150mg bid is the first treatment reducing strokes more than warfarin across the full spectrum of stroke risk in patients with AF.”

Stroke risk stratification scores such as CHADS₂ have been developed to guide appropriate use of anticoagulant therapy in patients with AF to maximise its benefit. For patients defined as being at high or moderate risk of stroke, the reduction in stroke risk with vitamin K antagonists (VKAs), such as warfarin, is likely to outweigh the risk of bleeding. For patients with a low risk CHADS₂ score, the benefits of VKAs are not as clear. Therefore, currently many patients only receive Aspirin, which is less effective than warfarin in reducing the risk of stroke, leaving patients insufficiently protected from the threat of severe and highly debilitating strokes.

Dr Jonas Oldgren continues, “Healthcare professionals and patients have long been waiting for a treatment that can provide stroke prevention across all levels of risk. We have shown that dabigatran etexilate provides greater benefits in stroke reduction across patients at low, medium and high risk, as well as reduced bleeding vs. warfarin in patients at low risk. This provides important evidence of the clear benefit that this novel oral anticoagulant can provide over current treatment with VKAs, such as warfarin.”

Up to three million people worldwide suffer strokes related to AF each year, which tend to be especially severe and disabling, with half of people dying within one year.