Economic evaluation of dabigatran etexilate for the prevention of venous thromboembolism after total knee and hip replacement surgery

Abstract

Objective: This was an evaluation of the cost-effectiveness of oral dabigatran etexilate compared with subcutaneous low-molecular-weight heparin (enoxaparin) for the prevention of venous thromboembolism (VTE) after total knee replacement (TKR) and total hip replacement (THR) surgery from the perspective of the UK National Health Service. Methods: Dabigatran etexilate (220 mg once daily) was compared with enoxaparin (40 mg once daily) in patients undergoing TKR (duration of prophylaxis, 6–10 days) and THR (duration of prophylaxis, 28–35 days). The 10-week acute postsurgical phase was modeled using a decision tree. A Markov process (1-year cycle length) was used to model long-term events (recurrent VTE, postthrombotic syndrome, and consequences of intracranial hemorrhage) for patients' remaining lifetimes. Relative risks for VTE and bleeding events were derived from 2 Phase III studies that compared dabigatran etexilate with enoxaparin 40 mg once daily. The probabilities of long-term events were estimated using data from published longitudinal studies. Results: Rates of VTE and bleeding events did not differ significantly between dabigatran etexilate and enoxaparin. Dabigatran etexilate was less costly than enoxaparin in TKR and substantially less costly in THR, primarily due to differences in administration costs. The cost of prophylaxis for THR patients, including drugs and administration costs, was estimated at £137 for dabigatran etexilate and £237 for enoxaparin (£7 for nursing time during the hospital stay, £91 for nurse home visits for administration after hospital discharge, and an additional £2 in drug costs). At a willingness-to-pay threshold of £20,000 per quality-adjusted life-year, the probability of cost-effectiveness for dabigatran etexilate was 75% in TKR and 97% in THR. These results were robust across a range of sensitivity analyses. Conclusion: From the perspective of the UK National Health Service, thromboprophylaxis with dabigatran etexilate was cost-saving compared with enoxaparin 40 mg once daily, with comparable efficacy and safety profiles.