Cost Effectiveness of Rivaroxaban Versus Warfarin for the Prevention of Recurrent Venous Thromboembolism.

Abstract

AbstractAbstract 3177 Background:Rivaroxaban is an oral anticoagulant administered once daily that works by direct inhibition of factor Xa. It has been found to be noninferior to warfarin in the prevention of recurrent venous thromboembolism (VTE). Whether rivaroxaban is cost effective in the prevention of recurrent VTE, however, is not known. Methods:To assess the cost effectiveness of rivaroxaban compared with warfarin in the prevention of recurrent VTE, we built a Markov state transition model over a 10-year time horizon. The base case analysis consisted of a hypothetical cohort of 60-year-old patients who were diagnosed with their first VTE and received secondary prophylaxis with either rivaroxaban or warfarin for 6 months. Cost estimates were derived from the Healthcare and Utilization Project (HCUP) and other sources. Probabilities for VTE recurrence and mortality and for major and minor bleeding were based on the EINSTEIN PE trial (NEJM 2012; 366: 1287–97). Outcomes included costs in 2011 United States dollars, quality adjusted life years (QALYs), and incremental cost effectiveness ratios (ICERs) over 10 years from a societal perspective. Results:Base case results are shown in the Table, showing total medication and other medical costs associated with each strategy. Compared with warfarin, the rivaroxaban strategy cost less ($4057 vs $7004) and was more effective (9.30 QALYs vs 9.16 QALYs). Thus, warfarin was dominated by rivaroxaban. In sensitivity analyses, results were most sensitive to changes in the probability of major bleeding with rivaroxaban. As shown in the Figure, when major bleeding with rivaroxaban (base case 1.1%) was less than 4.5%, the ICRE was within the $100,000 per QALY gained acceptability threshold range. Results favoring rivaroxaban were robust to individual variation of other parameter values. Conclusion:Prophylactic anticoagulation with rivaroxaban appears to be a cost effective, and perhaps cost saving, alternative to warfarin for the prevention of recurrent VTE.TableAnticoagulation StrategyCostIncremental CostEffectiveness (QALY)Incremental Effectiveness (QALY)Incremental C/E Ratio (ICER)1) Rivaroxaban$4057-9.30--2) Warfarin$7004$29479.16−0.14Dominated [Display omitted] Disclosures:Off Label Use: Rivaroxaban - Prevention of recurrent venous thromboembolism.