[The new anticoagulants].

Anticoagulant therapy is based on two veteran drugs, which have been in use for over 60 years: heparin and warfarin. Due to the limitations of these agents, new parenteral anticoagulants have been introduced, mainly the low molecular weight heparins, fondaparinux and direct thrombin inhibitors. The need to develop new drugs has led to major efforts by the pharmaceutical industry and many promising anticoagulant oral agents are being tested. Ximelgatran has been withdrawn from the market after several cases of hepatotoxicity have been observed. Two oral agents, dabigatran and rivaroxaban, have recently been approved in Europe. Dabigatran inhibits thrombin, while rivaroxaban is factor X inhibitor. Other drugs include apixaban, idraparinux and are in Phase III studies.