Indirect comparison based on the RE-LY trial for dabigatran etexilate and the ROCKET-AF trial for rivaroxaban suggests advantages of dabigatran in stroke prevention in patients with atrial fibrillation.
In the absence of a head-to-head study, a comprehensive analysis published in Thrombosis and Hemostasis, looks into the efficacy and cost-effectiveness of dabigatran etexilate (Pradaxa, Boehringer Ingelheim) for stroke prevention in patients with non-valvular atrial fibrillation in an indirect comparison to rivaroxaban (Xarelto, Bayer Healthcare). The analysis, based on two large scale trials including more than 32.000 patients combined, suggests that patients treated with dabigatran may have lower rates of ischaemic stroke and intracranial haemorrhage, and also accumulate lower costs from acute care and long-term follow-up over their lifetime than patients treated with rivaroxaban.
The authors conducted a formal indirect treatment comparison between dabigatran 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 healtheconomic 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:
- Dabigatran may provide a lower risk of stroke (RR=0.62; 95% CI 0.45-0.87) than rivaroxaban
- Dabigatran may provide a lower risk of intracranial haemorrhage (RR=0.38; 95% CI 0.21-0.67) than rivaroxaban
Looking at events per 100 patient-years, the model predicts that over a lifetime horizon, AF patients may experience:
- Considerably fewer intracranial haemorrhage with dabigatran than with rivaroxaban (0.33 vs. 0.71)
- Less ischaemic strokes with dabigatran than with rivaroxaban (3.40 vs. 3.96)
- More quality-of-life-years with dabigatran than with rivaroxaban (6.17 vs. 6.01)
When assessing the costs of care, the analysis implies that patients treated with dabigatran 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.The study shows consistent conclusions to previous analysis evaluating novel oral anticoagulant treatments in the Canadian market.
The indirect comparison model is based on data from ROCKET-AF where patients were treated with rivaroxaban and dabigatran clinical event rates as observed in the safety-on-treatment population in RE-LY, a prospective, randomised, 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. The dabigatran 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 algorithm for dabigatran.
Anuraag Kansal a research scientist in Health Economics, United BioSource Corporation, 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.”
