American Society of Hirudotherapy

Enhancement of recombinant tissue-type plasminogen activator thrombolysis with a selective factor Xa inhibitor derived from the leech Hirudo medicinalis: comparison with heparin and hirudin in a rabbit thrombosis model

Research article published in Coronary artery disease (1996)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Observational studyDrug DevelopmentSalivary PharmacologyKornowski R et al. · Coronary artery disease, 1996

Abstract

OBJECTIVE: To compare the efficacy of Yagin, a factor Xa inhibitor derived from the leech Hirudo medicinalis, with those of heparin and hirudin as adjuncts to recombinant tissue-type plasminogen activator (rTPA) thrombolysis in a rabbit thrombosis model. METHODS: Thirty-one animals were allocated randomly to three groups, all administered four boluses of 0.25 mg/kg rTPA every 10 min for 30 min, 17 mg/kg aspirin intravenously, and heparin (as a 100 IU/kg bolus followed by infusion of 50 IU/kg heparin per h), hirudin (as a 2 mg/kg bolus followed by infusion of 1 mg/kg hirudin per h), or Yagin (as an 80 micrograms/kg bolus followed by infusion of 43 micrograms/kg Yagin per h). RESULTS: Administration of Yagin was associated with a significant acceleration of the reflow time, this time being 14.5 +/- 1.2 min with Yagin, 25.8 +/- 5.2 min with heparin (P < 0.0001, versus Yagin), and 28.7 +/- 16.0 min with hirudin (P = 0.012, versus Yagin). Overall patency did not differ significantly among the three groups. CONCLUSIONS: At the indicated single doses, inhibition of factor Xa by a relatively low concentration of Yagin was found to be superior than that with either heparin or hirudin for accelerating rTPA thrombolysis.

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

Publication typeComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't
Indexed MeSH termsAnimalsAnticoagulantsAntithrombinsDisease Models, AnimalFactor Xa InhibitorsHeparinHirudin TherapyLeechesMyocardial ReperfusionPartial Thromboplastin TimeRabbitsRecombinant Proteins

Summary

To compare the efficacy of Yagin, a factor Xa inhibitor derived from the leech Hirudo medicinalis, with those of heparin and hirudin as adjuncts to recombinant tissue-type plasminogen activator (rTPA) thrombolysis in a rabbit thrombosis model.

Why This Matters for Hirudotherapy

This study compared the efficacy of Yagin, a factor Xa inhibitor derived from the leech Hirudo medicinalis, versus heparin and hirudin as adjuncts to recombinant tissue plasminogen activator (rTPA) thrombolysis in a rabbit thrombosis model involving 31 animals. Yagin significantly accelerated reflow time (14.5 ± 1.2 min) compared to both heparin (25.8 ± 5.2 min, P < 0.0001) and hirudin (28.7 ± 16.0 min, P = 0.012), though overall patency did not differ significantly among the three groups. This is directly relevant to ASH's domain, characterizing a bioactive anticoagulant from the medicinal leech and comparing its thrombolytic adjunct efficacy directly against hirudin in vivo. However, the study is limited to an animal model at single doses with a modest sample size, and clinical relevance is undemonstrated.

Citation

Enhancement of recombinant tissue-type plasminogen activator thrombolysis with a selective factor Xa inhibitor derived from the leech Hirudo medicinalis: comparison with heparin and hirudin in a rabbit thrombosis model

Kornowski R et al. · Coronary artery disease, 1996

DOI

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

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