Dr Abhishek Verma

¿ Warfarin and heparin are the traditional mainstay anticoagulant therapies for treating thromboembolic disease. ¿ These drugs, with a documented history of utility, also have inherent difficulties in usage; in particular, the complicated monitoring and numerous drug-drug interactions of warfarin, and the need for parenteral administration of heparins. ¿ New agents have recently emerged that target specific elements of the clotting pathway. Rivaroxaban, which inhibits activated factor X (Xa), is currently in clinical trials and is the most advanced factor Xa inhibitor. ¿ The drug offers once-daily oral dosing, with no need for injections, dose titration, or frequent blood tests to monitor the international normalised ratio. It has a rapid onset of action and, although there is no specific antidote, it has a short plasma elimination half-life (about 5-9 hours). ¿ Evidence from recently published large-scale phase III clinical trials shows rivaroxaban to be superior to enoxaparin for prophylaxis of venous thromboembolism after major orthopaeclic surgery. ¿ Studies have shown rivaroxaban to have a sound safety profile, with an incidence of bleeding similar to enoxaparin in phase III clinical trials. ¿ Few side effects and drug-drug interactions between rivaroxaban and common medications have been found thus far, although some interactions with potent cytochrome P450 3A4 inhibitors have been observed. ¿ It is hoped that rivaroxaban may be used as a first-line anticoagulant for prophylaxis of venous thromboembolic disease in postsurgical patients.