American Society of Hirudotherapy

Hirudin: clinical potential of a thrombin inhibitor

Research article published in Annual review of medicine (1994)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewDrug DevelopmentClinical TrialsJohnson P · Annual review of medicine, 1994

Abstract

Hirudin is the most potent and specific known inhibitor of thrombin, the enzyme that plays a key regulatory function in hemostasis and blood coagulation. The importance of thrombosis in cardiovascular disease has recently highlighted the limitations of existing antithrombotic drugs and the potential value of direct thrombin inhibition as an effective approach to antithrombotic therapy. Hirudin and a small peptidomimetic analog--hirulog--are being developed as alternatives to heparin for the treatment of unstable angina, for prevention of abrupt closure and restenosis following coronary angioplasty, for prevention of deep vein thrombosis after major orthopedic surgery, and as an adjunct to fibrinolytic therapy. Direct thrombin inhibitors have several potential advantages over heparin: They can inhibit thrombin bound to clots or extracellular matrices, which are relatively resistant to heparin; they do not require antithrombin III as a cofactor, which may lead to a more predictable dose response; and they are not inhibited by activated platelets, which release platelet factor 4 and other molecules that neutralize heparin. The results of early clinical studies suggest that hirudin and hirulog may be more efficacious and more predictable and may have fewer bleeding complications than heparin for several clinical indications.

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

Publication typeJournal ArticleResearch Support, Non-U.S. Gov'tReview
Indexed MeSH termsHeparinHirudin TherapyHirudinsHumansPeptide FragmentsRecombinant ProteinsStructure-Activity RelationshipThrombinThrombolytic TherapyThrombosis

Summary

Hirudin is the most potent and specific known inhibitor of thrombin, the enzyme that plays a key regulatory function in hemostasis and blood coagulation.

Why This Matters for Hirudotherapy

This review examines the clinical potential of hirudin—a potent and specific inhibitor of thrombin—and its synthetic analog, hirulog, as alternatives to heparin for managing thrombosis in cardiovascular disease and surgery. For the field of hirudotherapy, this article is conceptually relevant as it delineates the mechanistic advantages of direct thrombin inhibitors like hirudin, highlighting their ability to inactivate clot-bound thrombin, operate independently of antithrombin III, and resist neutralization by activated platelets. As a review article, it provides a synthesis of early clinical developments and pharmacological mechanisms rather than generating new experimental data. Therefore, its true value lies in establishing the foundational therapeutic rationale for hirudin rather than providing definitive, long-term clinical efficacy outcomes.

Citation

Hirudin: clinical potential of a thrombin inhibitor.

Johnson P · Annual review of medicine, 1994

DOI

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