Rivaroxaban versus enoxaparin after total knee arthroplasty

The RECORD4 study (May 16, p 1673)

showed that the new oral selective factor Xa inhibitor, rivaroxaban, given at a dose of 10 mg once daily is superior to enoxaparin given at the North-American-approved dose of 30 mg twice daily for the prevention of venous thromboembolism (VTE) after total knee arthroplasty. An earlier trial, the RECORD3 study,

showed that rivaroxaban 10 mg once daily was also superior to enoxaparin given at the European-approved dose of 40 mg once daily for prevention of VTE after total knee arthroplasty.

To our knowledge, no randomised trials have directly compared the North American and European enoxaparin dosing regimens in patients undergoing knee arthroplasty. Yet, indirect comparisons between the results of the RECORD4 and RECORD3 trials, and between the results of the REMOBILIZE trial

(which compared the new oral selective factor IIa inhibitor, dabigatran, with enoxaparin 30 mg twice daily) and the REMODEL trial

(dabigatran vs enoxaparin 40 mg once daily) indicate a more modest treatment effect of the new oral drug when compared against the North American enoxaparin dosing regimen than when compared against the European regimen (p≤0·10 for heterogeneity). These results suggest that enoxaparin 30 mg twice daily is substantially more effective than enoxaparin 40 mg once daily for the prevention of VTE in patients undergoing knee arthroplasty (table).