The new oral anticoagulants.

Although their first application in clinical practice occurred in the 1940s, vitamin K antagonists remain the only form of oral anticoagulant medication approved for long-term use. Although the available vitamin K antagonists are highly effective for the prevention and/or treatment of most thrombotic disease, the significant interpatient and intrapatient variability in dose-response, the narrow therapeutic index, and the numerous drug and dietary interactions associated with these agents have led clinicians, patients, and investigators to search for alternative agents. Three new orally administered anticoagulants (apixaban, dabigatran, and rivaroxaban) are in the late stages of development and several others are just entering (or moving through) earlier phases of investigation. These novel anticoagulant medications are being studied for the prevention and treatment of venous thromboembolism, the treatment of acute coronary syndromes and the prevention of stroke in patients with atrial fibrillation. This review summarizes published clinical trial data pertinent to apixaban, dabigatran, and rivaroxaban.