OBJECTIVES: Dabigatran etexilate (DBG) is a new direct thrombin inhibitor which is administered orally at a fixed dose. EMEA has approved DBG at a standard dose of 220mg once daily (od), and at a lower dose of 150mg od for patients aged over 75. Recent economic analyses for the UK have demonstrated that DBG 220mg od is cost-saving when compared with the commonly used agent, enoxaparin 40 mg od, with comparable efficacy and safety. This analysis investigates the cost-effectiveness of DBG 150mg od for the prevention of venous thromboembolism (VTE) in the subset of patients aged over 75 undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) from the perspective of the UK National Health Service.
METHODS: There was a comparison of DBG 150mg od to enoxaparin 40mg od using a decision model. Relative risks for VTE and bleeding events specific to patients aged over 75 were derived from sub-group analyses of the phase III DBG trials, RE-MODEL and RE-NOVATE. Probabilities of recurrent VTE and post-thrombotic syndrome were estimated from published longitudinal studies.
RESULTS: DBG was less costly than enoxaparin in TKR and substantially less so in THR, primarily due to differences in administration costs. VTE and bleeding rates were similar for DBG and enoxaparin; the probability of cost-effectiveness was 89% in TKR and 99% in THR at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year. These results were robust across a range of sensitivity analyses.
CONCLUSIONS: Thromboprophylaxis with DBG 150mg od in patients aged over 75 years is cost saving compared to enoxaparin 40 mg od, with comparable efficacy and safety.
