Cost effectiveness and clinical efficacy of Pradaxa® (dabigatran etexilate) versus rivaroxaban analysed

In the absence of a head-to-head study, a comprehensive analysis published in Thrombosis and Hemostasis,1 looks into the efficacy and cost-effectiveness of Pradaxa® for stroke prevention in patients with non-valvular atrial fibrillation in an indirect comparison to rivaroxaban. The analysis, based on two large scale trials including more than 32.000 patients combined, suggests that patients treated with Pradaxa® may have lower rates of ischaemic stroke and intracranial haemorrhage (ICH), and also accumulate lower costs from acute care and long-term follow-up over their lifetime than patients treated with rivaroxaban.1

The authors conducted a formal indirect treatment comparison between Pradaxa® and rivaroxaban (according to the Markov model).

The analysis has to be viewed in light of the absence of a head-to-head study. The current interest in health-economic aspects of new treatments may encourage further scientific assessments to confirm the findings. Boehringer Ingelheim would endorse and support further investigation.

In the analysis the authors conclude:1

• Pradaxa® may provide a lower risk of stroke (RR=0.62; 95% CI 0.45-0.87) than rivaroxaba
• Pradaxa® may provide a lower risk of intracranial haemorrhage (ICH) (RR=0.38; 95% CI 0.21-0.67) than rivaroxaba
• Looking at events per 100 patient-years, the model predicts that over a lifetime horizon, AF patients may experience
• Considerably fewer ICH with Pradaxa® than with rivaroxaban (0.33 vs. 0.71
• Less ischaemic strokes with Pradaxa® than with rivaroxaban (3.40 vs. 3.96
• More quality-of-life-years with Pradaxa® than with rivaroxaban (6.17 vs. 6.01)

When assessing the costs of care, the analysis implies that patients treated with Pradaxa® incur lower costs of acute care and long term follow-up per patient, which, according to the authors, more than offset differences in drug costs.1 The study shows consistent conclusions to previous analysis evaluating novel oral anticoagulant treatments in the Canadian market.2

The indirect comparison model is based on data from ROCKET AF3 where patients were treated with rivaroxaban and Pradaxa® clinical event rates as observed in the safety-on-treatment population4 in RE-LY®, a prospective, randomized, open-label trial with blinded endpoint evaluation, comparing two fixed doses of the oral direct thrombin inhibitor dabigatran etexilate (110mg and 150mg bid) each administered in a blinded manner, with open label warfarin.5,6 The Pradaxa® data were adjusted mainly to reflect the higher level of warfarin control in RE-LY®) (the mean TTR (TTR = time in therapeutic range) was 64% in RELY® and 55% in ROCKET-AF) and simulated dosing corresponding to the approved Canadian treatment algorithm7 for Pradaxa.

Dr Anuraag Kansal a research scientist in Health Economics, United BioSource Corporation, headquartered in the US said, “As more anticoagulation therapies become available, there is a need to understand the clinical and economic differences between new therapies. This research tells us that the benefits of dabigatran etexilate accrue steadily over time and that the novel oral anticoagulant continues to offer effective stroke protection for patients living with AF.”

Stroke Prevention in Atrial Fibrillation

AF is the most common sustained heart rhythm condition8, with one in four adults over the age of 409 developing the condition in their lifetime. People with AF are more likely to experience blood clots, which increases the risk of stroke by five-fold.9,10 Up to three million people worldwide suffer strokes related to AF each year.11-14 Strokes due to AF tend to be severe, with an increased likelihood of death (20%), and disability (60%).15

Ischaemic strokes are the most common type of AF-related stroke, accounting for 92% of strokes experienced by AF patients and frequently leading to severe debilitation.16-20 Appropriate anticoagulation therapy can help to prevent many types of AF-related strokes and improve overall patient outcomes.21

Worldwide, AF is an extremely costly public health problem, with treatment costs equating to $6.65 billion in the US and over €6.2 billion across Europe each year.21,22 Given AF-related strokes tend to be more severe, this results in higher direct medical patient costs annually.23 The total societal burden of AF-related stroke reaches €13.5 billion per year in the European Union alone.23

About the dabigatran etexilate clinical trial programme

Boehringer Ingelheim’s clinical trial programme to evaluate the efficacy and safety of dabigatran etexilate encompasses studies in:

• Primary prevention of venous thromboembolism (VTE) in patients undergoing elective total hip and knee replacement surgery
• Treatment of acute VTE
• Secondary prevention of VTE
• Stroke prevention in AF
• Prevention of thromboembolism after heart valve replacement.

References

1. Kansal A, et al. Dabigatran versus Rivaroxaban for the Prevention of Stroke and Systemic Embolism in Atrial Fibrillation in Canada: Comparative efficacy and cost-effectiveness. Thromb Haemost. 2012 Aug 17;108(4). [Epub ahead of print]
2. Canadian Agency for Drugs and Technology in Health. New Oral Anticoagulants for the Prevention of Thromboembolic Events in Patients with Atrial Fibrillation. April 9, 2012. Available at http://www.cadth.ca/media/pdf/NOAC_Therapeutic_Review_final_report.pdf
3. Patel MR, et al. Rivaroxaban versus warfarin in nonvalvular atrial fibrillation. N Engl J Med 2011;365(10):883-91.
4. Boehringer Ingelheim. Data on File.
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6. Connolly SJ, et al. Newly identified events in the RE-LY® trial. N Engl J Med 2010; 363(19):1875-6.
7. Boehringer Ingelheim Canada Ltd. PradaxTM Dabigatran Etexilate capsules product monograph.
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21. Coyne KS, et al. Assessing the direct costs of treating nonvalvular atrial fibrillation in the United States. Value Health 2006; 9:348-56.
22. Ringborg A, et al. Costs of atrial fibrillation in five European countries: results from the Euro Heart Survey on atrial fibrillation. Europace 2008; 10:403-11.
23. Brüggenjürgen B, et al. The impact of atrial fibrillation on the cost of stroke: the Berlin acute stroke study. Value Health 2007; 10:137-43.
24. Pradaxa®, European Summary of Product Characteristics, 2012.
25. Di Nisio M, et al. Direct thrombin inhibitors. N Engl J Med 2005; 353:1028-40.