American Society of Hirudotherapy

Clinical potential of oral direct thrombin inhibitors in the prevention and treatment of venous thromboembolism

Review published in Drugs (2004)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewDrug DevelopmentClinical TrialsAgnelli G · Drugs, 2004

Abstract

Current antithrombotic therapies are associated with various practical limitations and risks that restrict their utility in the management of venous thromboembolism. The coagulation factor, thrombin, has been the focus of extensive investigation as a pharmacological target in efforts to improve the management of venous thromboembolism. Hirudin, desirudin, bivalirudin and argatroban are direct thrombin inhibitors that have been launched for limited indications as anticoagulants. Their usefulness for long-term prophylaxis is limited by a requirement for parenteral administration, restricted licensing and bleeding/tolerability profile. Ximelagatran--which, after oral administration, is rapidly converted to its active form, melagatran--is the first oral direct thrombin inhibitor and the first new oral anticoagulant to become available in 60 years. Clinical studies have shown that melagatran/ximelagatran, without coagulation monitoring, is effective and well tolerated for the prevention of venous thromboembolism after hip replacement and knee replacement surgery. Ximelagatran is also effective in the acute treatment of venous thromboembolism and long-term secondary prevention of recurrent venous thromboembolism, the prevention of stroke in patients with atrial fibrillation and in the prevention of cardiovascular events after myocardial infarction. Oral direct thrombin inhibitors have a promising role in the management of venous thromboembolism and other associated medical conditions.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleReview
Indexed MeSH termsAnticoagulantsAzetidinesBenzylaminesClinical Trials as TopicHumansOrthopedic ProceduresPostoperative ComplicationsThrombinVenous Thrombosis

Summary

Current antithrombotic therapies are associated with various practical limitations and risks that restrict their utility in the management of venous thromboembolism.

Why This Matters for Hirudotherapy

This review examines oral direct thrombin inhibitors for prevention and treatment of venous thromboembolism, noting that hirudin, desirudin, bivalirudin, and argatroban have been launched for limited anticoagulant indications but require parenteral administration. The abstract focuses on ximelagatran/melagatran, reporting clinical effectiveness for VTE prophylaxis after orthopedic surgery, acute VTE treatment, and stroke prevention in atrial fibrillation without coagulation monitoring. For ASH's domain, the review is relevant insofar as hirudin and its derivatives are framed as parenteral predecessors whose practical limitations motivated development of oral alternatives. Caveat: This is a pharmacology review centered on a synthetic oral anticoagulant; it does not address hirudotherapy or live leech application, and all clinical claims pertain to pharmaceutical DTIs.

Citation

Clinical potential of oral direct thrombin inhibitors in the prevention and treatment of venous thromboembolism.

Agnelli G · Drugs, 2004

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