American Society of Hirudotherapy

WA3-1

Eleven-residue anticoagulant + thrombolytic peptide from Whitmania pigra alcalase hydrolysate — Ren 2016 documents activity in aPTT, PT, and TT assays with thrombolytic effect.

Preclinical / mechanisticLast updated: 2026-05-27 · Reviewed by ASH Editorial Board
Molecular weight of WA3-1 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 kDaWA3-11.4 kDa
Molecular weight (kilodaltons) of WA3-1 (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
Eleven-residue anticoagulant + thrombolytic peptide from Whitmania pigra alcalase hydrolysate — Ren 2016 documents activity in aPTT, PT, and TT assays with thrombolytic effect.
Evidence level
In vitro
Drug vs leech
Purified natural compound
Safety domains
Bleeding

Clinical translation limit

WA3-1's in vitro anticoagulant + thrombolytic dual activity does NOT establish clinical efficacy. No FDA-approved derivative exists; W. pigra is a non-hematophagous TCM leech, not the FDA-cleared K040187 medicinal leech.

Molecular Profile

Category
Anticoagulant
Evidence tier
Preclinical
Molecular weight
1,422 Da
Source species
Whitmania pigra
Discovered
2016 · Ren Y et al.
WA3-1 molecular structure

Biological Targets

  • aPTT-PT-TT triple-pathway prolongation
  • thrombolytic activity

Key Citations

  1. Ren Y et al. (2016), Amino Acids · PMID 27487778

External Resources

    Related Anticoagulant Compounds

    This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.