LAPP (Leech Anti-Platelet Protein)
Antiplatelet protein from Haementeria officinalis — vWF-A1 / collagen-binding inhibitor with reported antithrombotic activity in preclinical models.
Preclinical / mechanisticLast updated: 2026-05-26 · Reviewed by ASH Editorial Board
Mechanistic Evidence Box
Preclinical / mechanistic- Page type
- Compound profile
- Evidence type
- Antiplatelet protein from Haementeria officinalis — vWF-A1 / collagen-binding inhibitor with reported antithrombotic activity in preclinical models.
- Evidence level
- In vitro
- Drug vs leech
- Purified natural compound
- Safety domains
- Bleeding
Clinical translation limit
LAPP's preclinical activity in animal thrombosis models did NOT translate into an FDA-approved drug. Pharmaceutical development was not advanced. Mechanism does NOT establish clinical efficacy of whole-leech therapy.
Molecular Profile
- Category
- Antiplatelet
- Evidence tier
- Preclinical
- Molecular weight
- 13,000 Da
- Source species
- Haementeria officinalis
- Discovered
- 1992 · Connolly TM et al.
Biological Targets
- → von Willebrand factor A1 domain
- → collagen-platelet adhesion
Key Citations
- Connolly TM et al. (1992), J Biol Chem · PMID 1551897
- Keller PM et al. (1992), J Biol Chem · PMID 1551898
External Resources
Related Antiplatelet Compounds
Calin
Anti-platelet adhesion protein that blocks von Willebrand factor–collagen binding.
Saratin
Anti-platelet adhesion protein blocking collagen-mediated platelet activation.
Decorsin
RGD-containing peptide inhibiting platelet GP IIb/IIIa receptor — eptifibatide ancestor.
Ornatin
RGD-peptide GP IIb/IIIa antagonist — sister molecule to decorsin from a different leech species.