Rivaroxaban: A Novel, Oral, Direct Factor Xa Inhibitor

Thromboembolic disorders such as deep vein thrombosis, pulmonary embolism, myocardial infarction, and stroke often result in long-term disability and/or mortality The anticoagulants currently available have been effective in the treatment and prevention of these disorders; however, parenteral administration, variable pharmacokine tics and pharmacodynamics, drug and dietary interactions, and a requirement for frequent monitoring of efficacy and safety limit use of these drugs. Rivaroxaban is a novel, oral factor Xa inhibitor in clinical development for the treatment and prevention of thromboembolic diseases. Rivaroxaban is a small molecule directed at active sites, and the agent mechanistically differs from traditional anticoagulants, such as heparins and fondaparinux, in that its activity is independent of antithrombin and its ability to inhibit prothrombinase bound factor Xa. In addition, preclinical and clinical trial data indicate that rivaroxaban has predictable pharmacokinetics and pharmacodynamics, which are features that differentiate it from oral vitamin K antagonists. Phase II studies showed that rivaroxaban is safe and well tolerated across a wide range of doses. Furthermore, completed phase III studies demonstrated its efficacy in the prevention of venous thromboembolism after orthopedic surgery. Additional studies are now under way to evaluate the use of rivaroxaban in the treatment and prevention of other venous and arterial thromboembolic conditions.