New Oral Anticoagulants for Venous Thromboembolism: Focus on Factor Xa and Thrombin Inhibitors

Several oral direct anti-Xa agents and one antithrombin agent are currently under clinical development for the prevention and treatment of venous thromboembolism (VTE). The anti-Xa inhibitors rivaroxaban (10 mg once daily) and apixaban (2.5 mg twice daily) as well as the thrombin inhibitor dabigatran (150 or 220 mg once daily) have been recently licensed for the prevention of VTE in total hip or knee replacement. The publication of the results of studies with rivaroxaban and apixaban in the prevention of VTE in medical patients are awaited. Phase III studies on the treatment of VTE showed the non inferiority of rivaroxaban (15 mg twice daily in the first three weeks and 20 mg once daily thereafter) and dabigatran (150 mg twice daily) to standard treatment. The incidence of major or clinically relevant non-major bleeding was similar in patients receiving standard treatment and rivaroxaban or dabigatran. Clinical trials on VTE treatment are currently ongoing with apixaban and edoxaban. A number of phase II clinical trials are currently ongoing with several other antiXa agents in the prophylaxis and treatment of VTE. Keywords: Anticoagulant therapy, antithrombotic therapy, anticoagulants, direct thrombin inhibitors, Factor Xa inhibitors