Abstract

Ximelagatran for stroke prevention in atrial fibrillation

Author(s): Amar M Salam

For decades, warfarin has been the gold standard anticoagulant that is recommended in patients with atrial fibrillation for the prevention of stroke and systemic embolic events. However, warfarin therapy has several disadvantages; including significant risks of bleeding, a narrow therapeutic margin necessitating frequent monitoring and interactions with numerous drugs and foods. These limitations created a need for safer, more convenient alternative anticoagulants for stroke prevention. Ximelagatran (Exanta^™, Astrazeneca) is a novel, oral direct thrombin inhibitor that inhibits the final step in the coagulation process, namely, the conversion of fibrinogen to insoluble fibrin by thrombin. It has a rapid onset of action, a relatively wide therapeutic margin and a low potential for food and drug interactions. In addition, it can be administered in a fixed dosage, which obviates the need for anticoagulation monitoring, thus simplifying treatment and improving compliance. The Stroke Prevention Using Oral Thrombin Inhibitor in Atrial Fibrillation (SPORTIF) program has been investigating the safety and efficacy of ximelagatran for the prevention of stroke in patients with AF. This report discusses the implications of the recently published Phase III trial, SPORTIF III, which evaluated the efficacy and safety of ximelagatran as compared with warfarin in high-risk patients with AF.