Direct inhibitors of coagulation proteins - the end of the heparin and low-molecular-weight heparin era for anticoagulant therapy?

Thromb Haemost. 2009 Nov;102(5):892-9. doi: 10.1160/TH09-02-0134.

Abstract

Heparins, either unfractionated or low-molecular-weight (UFH and LMWHs), and vitamin K antagonists (VKAs) are currently the anticoagulants of choice for the prevention of post-operative venous thromboembolism (VTE) and for the treatment of acute venous and arterial thromboembolism. While VKAs are widely used in the US, LMWHs are the standard of care in the EU. Although efficacious, these agents are associated with a number of drawbacks, such as the risk of heparin-induced thrombocytopenia, the need for frequent coagulation monitoring in the case of UFH and VKAs, and the parenteral mode of administration in the case of heparins, which can lead to problems associated with patient compliance. There is a need for new anticoagulants that overcome these limitations. Direct, small-molecule inhibitors of coagulation proteins targeting a single enzyme in the coagulation cascade - particularly thrombin or Factor Xa - have been developed in recent years. Two agents, the direct thrombin inhibitor dabigatran and the direct Factor Xa inhibitor rivaroxaban, have recently been approved in the EU and several other countries for the prevention of VTE after total hip or knee replacement surgery. Here we will review data that suggest that the antithrombin-independent mechanism of action of these agents, particularly that of direct Factor Xa inhibitors, leads to increased efficacy with similar safety profiles compared with the antithrombin-dependent heparins. Although the end of the heparins era is not to be expected, the new anticoagulants presented in this review potentially represent the future of anticoagulation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Anticoagulants / chemistry
  • Anticoagulants / pharmacology*
  • Anticoagulants / therapeutic use
  • Antithrombin III / antagonists & inhibitors
  • Blood Coagulation Factors / antagonists & inhibitors*
  • Clinical Trials as Topic
  • Drug Design
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology
  • Enzyme Inhibitors / therapeutic use
  • Factor V / antagonists & inhibitors
  • Factor Xa
  • Factor Xa Inhibitors
  • Hemorrhage / chemically induced
  • Heparin / pharmacology
  • Heparin / therapeutic use
  • Heparin, Low-Molecular-Weight / pharmacology
  • Heparin, Low-Molecular-Weight / therapeutic use
  • Humans
  • Molecular Weight
  • Postoperative Complications / chemically induced
  • Postoperative Complications / prevention & control
  • Purpura, Thrombocytopenic, Idiopathic / chemically induced
  • Purpura, Thrombocytopenic, Idiopathic / prevention & control
  • Thrombophilia / drug therapy*
  • Venous Thromboembolism / prevention & control
  • Vitamin K / antagonists & inhibitors

Substances

  • Anticoagulants
  • Blood Coagulation Factors
  • Enzyme Inhibitors
  • Factor Xa Inhibitors
  • Heparin, Low-Molecular-Weight
  • prothrombinase complex
  • Vitamin K
  • Antithrombin III
  • Factor V
  • Heparin
  • Factor Xa