Ornatin
RGD-peptide GP IIb/IIIa antagonist — sister molecule to decorsin from a different leech species.
Praeklinisch / mechanistischLast updated: 2026-05-26 · Reviewed by ASH Editorial Board
Mechanistic Evidence Box
Preclinical / mechanistic- Page type
- Compound profile
- Evidence type
- RGD-peptide GP IIb/IIIa antagonist — sister molecule to decorsin from a different leech species.
- Evidence level
- In vitro
- Drug vs leech
- Purified natural compound
- Safety domains
- Bleeding
Clinical translation limit
Ornatin's in vitro antagonism of platelet GP IIb/IIIa does not establish clinical efficacy. No FDA-approved derivative exists. Mechanism is preclinical/biochemical only.
Molecular Profile
- Category
- Antiplatelet
- Evidence tier
- Preclinical
- Molecular weight
- 5,500 Da
- Source species
- Placobdella ornata
- Discovered
- 1991 · Mazur et al.
Biological Targets
- → platelet integrin αIIbβ3 (GP IIb/IIIa)
Key Citations
- Mazur P et al. (1991), J Biol Chem
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.
Eptifibatide
Cyclic heptapeptide GP IIb/IIIa receptor antagonist — FDA approved 1998. Structural inspiration: leech decorsin.