Boehringer Ingelheim Pharmaceuticals, Inc., the largest US subsidiary of Boehringer Ingelheim Corporation and a member of the Boehringer Ingelheim group of companies, presented study results from a new retrospective sub-analysis of the RE-LY trial that indicated patients with non-valvular atrial fibrillation (NVAF) who also have diabetes experienced similar safety and efficacy with Pradaxa (dabigatran etexilate mesylate) 150mg or dabigatran 110mg relative to warfarin, in comparison to patients with NVAF who do not have diabetes. This data was presented today during the American Heart Association's Scientific Sessions 2012.
Diabetes affects 25.8 million Americans. It is one of the most common conditions associated with atrial fibrillation (AFib), and patients with both conditions have up to double the risk of experiencing a stroke compared to those with only Afib.
"These results are encouraging, as they indicate Pradaxa 150 mg twice daily is effective in this higher risk NVAF patient population, a group in need of effective treatments," said Paul Reilly, clinical programme director, Boehringer Ingelheim Pharmaceuticals, Inc.
Of the 18,113 patients in the RE-LY trial, 4,221 patients (23 percent) had diabetes when the trial began. This sub-analysis examined patient characteristics and outcomes of patients with NVAF, comparing those with and without diabetes, and the relative efficacy of Pradaxa 150mg twice daily or dabigatran 110mg twice daily versus warfarin, using an interaction p-value.
The results show that patients with diabetes in the RE-LY study had a higher prevalence of additional cardiovascular diseases (e.g., hypertension), and for diabetic patients with NVAF randomized to warfarin, INR was not as well-controlled. Despite this, the sub-analysis indicates that patients with NVAF and diabetes, compared to patients with NVAF without diabetes, derive similar relative outcomes from Pradaxa 150mg or dabigatran 110mg compared to warfarin.
"It is common for patients with atrial fibrillation to have co-morbidities, such as diabetes," said Harald Darius, Vivantes Berlin-Neukolln Medical Center, Germany. "These findings are important and relevant since nearly one out of four patients with NVAF in the RE-LY study also had diabetes."
The sub-analysis found that patients with diabetes were younger (70.9 vs. 71.7 years, p<0.01) and more likely to have other cardiovascular diseases, including hypertension (86.6 per cent vs. 76.5 per cent, p<0.01), coronary artery disease (37.4 per cent vs. 24.9 per cent, p<0.01) and peripheral vascular disease (5.6 per cent vs. 3.2 per cent, p<0.01). Compared to RE-LY patients without diabetes, those with diabetes had a higher risk of strokes and major bleeds, except intracranial bleeding.
RE-LY was a global, phase III, randomized trial of 18,113 patients enrolled in 951 centres in 44 countries, investigating whether dabigatran etexilate (two blinded doses) was as effective as open-label warfarin – INR 2.0 - 3.0 – for stroke prevention. Patients with non-valvular AFib and at least one other risk factor for stroke (i.e., previous ischemic stroke, transient ischemic attack, or systemic embolism, left ventricular ejection fraction <40 per cent, symptomatic heart failure, New York Heart Association Class > 2, age > 75 years, age > 65 years with either diabetes mellitus, history of coronary artery disease, or hypertension) were enrolled in the study for two years with a minimum follow-up period of one year.
The RE-LY trial utilized the established PROBE (prospective, randomized, open-label, blinded endpoint evaluation) clinical trial protocol, which has been used in the previous trials of anticoagulation for stroke prevention in patients with AFib. A PROBE design may reflect the differences in the management of warfarin and dabigatran in clinical practice.
The primary endpoint of the trial was incidence of stroke (including ischemic and haemorrhagic) and systemic embolism. The primary safety endpoint was major bleeding, defined as a reduction in the haemoglobin level of at least 2.0 g/dL, transfusion of at least 2 units of blood, or symptomatic bleeding in a critical area or organ. Other safety endpoints included bleeding events (major and minor), intracerebral haemorrhage, other intracranial haemorrhage, elevations in liver transaminases, bilirubin and hepatic dysfunction and other adverse events.
Pradaxa is indicated to reduce the risk of stroke and systemic embolism in patients with non-valvular atrial fibrillation.