Rivaroxaban, an oral, direct factor Xa inhibitor: a new option for thromboprophylaxis.

Patients undergoing major orthopedic surgery, including total hip arthroplasty (THA) and total knee arthroplasty (TKA), are at high risk for developing venous thromboembolism (VTE). Although largely a preventable complication, VTE develops in a significant proportion of patients, highlighting the need for improved methods of VTE prevention. Current thromboprophylactic options are limited by unpredictable pharmacokinetics and pharmacodynamics (vitamin K antagonists), parenteral/subcutaneous administration (heparin and low-molecular-weight heparins), complicated dosing, and increased risk of bleeding.Rivaroxaban is an oral, direct Factor Xa inhibitor that has recently received marketing authorization in the United States for prophylaxis of deep vein thrombosis in patients undergoing hip or knee replacement surgery. The clinical pharmacology of rivaroxaban supports a convenient, oral, once-daily dosing regimen without the need for routine coagulation monitoring after THA or TKA. A comprehensive phase II and III study program supports its safety and efficacy for VTE prevention after THA or TKA. Phase III results have demonstrated the superior efficacy of rivaroxaban regimens compared with enoxaparin regimens, with similar rates of major bleeding. This article provides an overview of the phase II and III results that support the use of this agent for the prevention of VTE after elective total hip or knee replacement.