Hirudin-Like Factor 4 (HLF4, European Medicinal Leeches)
Paralogous hidden hirudin-like factor in H. medicinalis / verbana / orientalis whose native form has minimal anticoagulant activity — Müller 2020 structure-activity engineering.
Preclinical / mechanisticLast updated: 2026-05-28 · Reviewed by ASH Editorial Board
Mechanistic Evidence Box
Preclinical / mechanistic- Page type
- Compound profile
- Evidence type
- Paralogous hidden hirudin-like factor in H. medicinalis / verbana / orientalis whose native form has minimal anticoagulant activity — Müller 2020 structure-activity engineering.
- Evidence level
- In vitro
- Drug vs leech
- Recombinant (genetically expressed)
- Safety domains
- Bleeding
Clinical translation limit
HLF4's engineered anticoagulant activity in vitro does NOT establish clinical efficacy. No FDA-approved derivative.
Molecular Profile
- Category
- Anticoagulant
- Evidence tier
- Preclinical
- Source species
- Hirudo medicinalis / verbana / orientalis
- Discovered
- 2020 · Müller C et al.
Biological Targets
- → thrombin (weak native; engineered enhancement possible via N-terminal + central-domain modifications)
Key Citations
- Müller C et al. (2020), Parasitol Res · PMID 32363441
External Resources
Related Anticoagulant Compounds
Hirudin
The most potent natural thrombin inhibitor — and the molecular template for three FDA-approved direct thrombin inhibitor drugs.
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.