American Society of Hirudotherapy

Tridegin

Factor XIIIa inhibitor — blocks fibrin cross-linking; novel mechanism distinct from hirudin.

Preclinical / mechanisticLast updated: 2026-05-26 · Reviewed by ASH Editorial Board
Molecular weight of Tridegin compared with other characterized leech-derived compoundsHementerin80 kDaHementin80 kDaHementin-Like Protein (HLP-1)80 kDaLeech Collagenase70 kDaHaemadipsa yanyuanensis Progr…70 kDaLeech Apyrase67 kDaCalin65 kDaHyaluronidase60 kDaAntithrombin III binding prot…58 kDaCollagenolytic Fibrinolysin55 kDaLeech Thrombospondin-Like Pro…50 kDaTridegin8.4 kDa
Molecular weight (kilodaltons) of Tridegin (highlighted) alongside other characterized leech salivary compounds. Smaller proteins/peptides generally diffuse and act faster.

Mechanistic Evidence Box

Preclinical / mechanistic
Page type
Compound profile
Evidence type
Factor XIIIa inhibitor — blocks fibrin cross-linking; novel mechanism distinct from hirudin.
Evidence level
In vitro
Drug vs leech
Purified natural compound
Safety domains
Bleeding

Clinical translation limit

Tridegin's in vitro inhibition of Factor XIIIa does not establish clinical efficacy. No FDA-approved Factor XIIIa inhibitor exists. Mechanism is preclinical/biochemical only.

Molecular Profile

Category
Anticoagulant
Evidence tier
Preclinical
Molecular weight
8,400 Da
Source species
Haementeria ghilianii
Discovered
1997 · Finney S et al.
Tridegin molecular structure

Biological Targets

  • → Factor XIIIa (transglutaminase)

Key Citations

  1. Finney S et al. (1997), Biochem J · PMID 9210403

External Resources

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    Ghilanten

    Factor Xa inhibitor with anti-metastatic activity in animal cancer models — translational dual-use compound.

    Lefaxin

    Factor Xa inhibitor with anti-inflammatory properties.

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