Abstract
Hypothesis
Pre-specified pooling of data from the four phase III RECORD studies was conducted to determine whether rivaroxaban significantly reduced the less-frequent clinical endpoint of symptomatic venous thromboembolism (VTE) and all-cause mortality after total hip or knee arthroplasty (THA or TKA, respectively), compared with standard North American and European enoxaparin regimens.
Methods and analysis
Patients (n=12,729) received rivaroxaban 10 mg once daily or enoxaparin 40 mg once daily (RECORD1-3) or 30 mg 12-hourly (RECORD4). Thromboprophylaxis was administered for 31-39 days (RECORD1; THA) or 10-14 days (RECORD3 and 4; TKA). RECORD2 (THA) compared 31-39 days' rivaroxaban with 10-14 days' enoxaparin followed by placebo. The pre-specified primary efficacy endpoint in the pooled analysis (composite of symptomatic VTE and all-cause mortality) and adjudicated bleeding events were analysed in the day 12±2 active treatment pool, when all patients had received active drug, and total treatment duration pool, where subgroup analyses were performed.
Results
In the day 12±2 active treatment pool, the primary efficacy endpoint occurred in 0.5% of patients receiving rivaroxaban versus 1.0% of patients receiving enoxaparin (p=0.001). Major bleeding occurred in 0.3% versus 0.2% patients respectively (p=0.18) and major plus clinically relevant non-major bleeding occurred in 2.9% versus 2.5% patients respectively (p=0.19). In the total treatment duration pool, rivaroxaban significantly reduced the primary efficacy endpoint compared with enoxaparin regimens 0.6% versus 1.3% patients (p< 0.001) with similar rates of major bleeding. Over the total treatment period, rivaroxaban consistently reduced the primary efficacy endpoint across the pre-specified subgroups (age, gender, body weight, creatinine clearance).
Conclusion
Rivaroxaban significantly reduced the composite of clinically important symptomatic VTE and all-cause mortality after THA or TKA compared with subcutaneous enoxaparin regimens in the direct comparison day 12±2 active treatment pool, with no significant differences in bleeding events. These results suggest a positive benefit-risk profile for oral, once-daily rivaroxaban.