Perspectives on antithrombotic agents: from unfractionated heparin to new antithrombotics

• Published in: Haematologica (Roma) 2002-07, Vol.87 (7), p.757-770
• Main Authors: Agnelli, G, Sonaglia, F
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Blood Coagulation Factors - antagonists & inhibitors; Blood. Blood coagulation. Reticuloendothelial system; Fibrinolytic Agents - adverse effects; Fibrinolytic Agents - pharmacokinetics; Fibrinolytic Agents - therapeutic use; Heparin - adverse effects; Heparin - pharmacokinetics; Heparin - therapeutic use; Heparin, Low-Molecular-Weight - adverse effects; Heparin, Low-Molecular-Weight - pharmacokinetics; Heparin, Low-Molecular-Weight - therapeutic use; Humans; Medical sciences; Pharmacology. Drug treatments; Postoperative Complications - drug therapy; Postoperative Complications - prevention & control; Serine Proteinase Inhibitors - pharmacokinetics; Serine Proteinase Inhibitors - therapeutic use; Thrombosis - drug therapy; Thrombosis - prevention & control
• ISSN: 0390-6078; 1592-8721

Division of Internal and Cardiovascular Medicine, Department of Internal Medicine, University of Perugia, via Enrico dal Pozzo, 06126 Perugia, Italy. [e-mail] BACKGROUND AND OBJECTIVES: Unfractionated heparin (UFH) has been the antithrombotic agent of choice for the prevention and treatment of venous thromboembolism (VTE) for a long time. UFH is also widely used for the treatment of patients with acute coronary syndromes. However, UFH has some limitations such as the need for parenteral administration and close monitoring of its anticoagulant effect. UFH is also associated with bleeding, heparin-induced thrombocytopenia and osteoporosis. EVIDENCE AND INFORMATION SOURCES: Low molecular weight heparins (LMWHs) are produced by the depolymerization of UFH. LMWHs have pharmacologic advantages over UFH: a better bioavailability after subcutaneous administration, a longer plasma half-life and a more predictable anticoagulant effect. These improved features allow once or twice daily subcutaneous injection of weight-adjusted doses of LMWHs without requiring laboratory monitoring in patients with VTE or unstable angina. PERSPECTIVES: A number of new antithrombotic agents are currently under development. These include direct antithrombins and factor Xa inhibitors. The results of the main clinical trials with LMWHs as well as those of the studies with the new antithrombotic agents will be reviewed in this article.