Factor Xa Inhibitors in Acute Coronary Syndromes and Venous Thromboembolism

As an alternative to the inconvenient and labor intensive traditional anticoagulants, Factor Xa inhibitors may offer new options for the prevention and treatment of acute coronary syndromes (ACS) and venous thromboembolism (VTE). Fondaparinux, an indirect FXa inhibitor, has equivalent efficacy but decreased bleeding risk. It has been recommended by the American College of Cardiology (ACC)/American Heart Association (AHA) as the preferred anticoagulant in ACS patients with higher bleeding risk managed with a noninvasive strategy. Based on the composite results of several clinical trials, fondaparinux is also recommended for VTE prevention in the setting of major orthopedic surgery. Rivaroxaban, a direct FXa inhibitor, appears to have at least equal efficacy and safety to established anticoagulants in the prevention of VTE. With advantages such as oral administration and a wide therapeutic window, it may provide a useful alternative to current anticoagulants. Ongoing studies are exploring its use in treatment of VTE and ACS, as well as prevention of stroke among patients with atrial fibrillation. In this review, we examine the key recent studies on efficacy and safety of FXa inhibitors in ACS and VTE management.