Hirudin
The most potent natural thrombin inhibitor — and the molecular template for three FDA-approved direct thrombin inhibitor drugs.
Mechanistic Evidence Box
Preclinical / mechanistic- Page type
- Compound profile
- Evidence type
- The most potent natural thrombin inhibitor — and the molecular template for three FDA-approved direct thrombin inhibitor drugs.
- Evidence level
- In vitro
- Drug vs leech
- Purified natural compound
- Safety domains
- Bleeding · Allergy / anaphylaxis
Clinical translation limit
Hirudin's direct thrombin binding in vitro and in animal models does NOT establish therapeutic efficacy of whole medicinal-leech therapy for any indication outside FDA-cleared microsurgical flap salvage (K040187). Pharmaceutical use of natural hirudin is rare; FDA-approved recombinant analogs (lepirudin, desirudin) and the synthetic analog bivalirudin are separate drugs with their own clinical evidence base.
Molecular Profile
- Category
- Anticoagulant
- Evidence tier
- Tier A — FDA-approved derivative
- Molecular weight
- 7,000 Da
- Source species
- Hirudo medicinalis
- Discovered
- 1884 · John Berry Haycraft (University of Edinburgh)
- Derived FDA-approved drug
- Lepirudin (Refludan), Desirudin (Iprivask), Bivalirudin (Angiomax)
Biological Targets
- → thrombin (Factor IIa)
Key Citations
- Haycraft JB (1884), Proc R Soc Lond
- Markwardt F (1957), Naturwissenschaften
- Stone SR, Hofsteenge J (1986), Biochemistry · PMID 3768302
External Resources
Related Anticoagulant Compounds
Antistasin
Factor Xa inhibitor — prototype molecule that inspired the entire DOAC drug class (rivaroxaban, apixaban).
Ghilanten
Factor Xa inhibitor with anti-metastatic activity in animal cancer models — translational dual-use compound.
Lefaxin
Factor Xa inhibitor with anti-inflammatory properties.
Hirudin-PA
Hirudin variant from Hirudinaria manillensis with distinct kinetics.