Elafin

Summary

Elafin (also known as trappin-2 or SKALP) is an endogenous 9.9 kDa cysteine-rich peptide produced by epithelial cells, keratinocytes, and immune cells. It functions as a potent inhibitor of neutrophil elastase and proteinase 3, protecting tissues from excessive proteolytic damage during inflammation. Recombinant forms are under investigation for conditions including acute lung injury, cardiovascular surgery, cystic fibrosis, and inflammatory bowel disease. It also has intrinsic antimicrobial and anti-biofilm activities.

Mechanism of Action

Elafin is an endogenous serine protease inhibitor that irreversibly inhibits neutrophil elastase and proteinase 3, thereby reducing extracellular matrix degradation and modulating inflammatory responses. It also exhibits antimicrobial properties by disrupting microbial membranes and has immunomodulatory effects through NF-κB pathway inhibition.

Routes of Administration

Goals & Uses

• Vaginal dysbiosis / preterm birth preventionReproductive / AntimicrobialLow
• Cardiac surgery-associated inflammationPerioperative CytoprotectionModerate
• Antimicrobial defenseAntimicrobial Peptide ActivityModerate
• Acute lung injury / ARDS protectionAnti Inflammatory / Tissue ProtectionModerate
• Inflammatory bowel diseaseGastroenterologyLow
• Cystic fibrosis airway inflammationPulmonary Anti InflammatoryModerate

Contraindications

• Known hypersensitivity to elafin or excipientsAllergic / ImmunologicHigh
• Severe coagulopathyHematologicModerate

Adverse Effects

• Injection site reactionsLocalUncommon
• Airway irritationPulmonaryUnknown
• Immunogenicity / antibody formationImmunologicUnknown
• Transient hypotensionCardiovascularUncommon

Drug Interactions

• Anticoagulants (e.g., heparin, warfarin)Low
• Recombinant human DNase (dornase alfa)Low

Population Constraints

• Patients with active malignancyOncologyRelative
• Pediatric patientsAgeRelative
• Pregnant womenReproductiveRelative

Regulatory Status

• European UnionInvestigationalEarly-phase European clinical trials conducted (e.g., cardiac surgery). No EMA marketing authorization.
• United StatesInvestigationalNo FDA-approved product; IND-stage research ongoing for cardiac surgery and lung injury indications.
• United KingdomInvestigationalMHRA has not approved any elafin therapeutic product; UK academic groups involved in elafin research.

No approved therapeutic formulation exists as of 2024. Recombinant elafin (e.g., delivered via Lactococcus lactis or adenoviral vectors) is under preclinical and early-phase clinical investigation. Elafin-based constructs have been explored in Phase I/II studies for cardiac surgery and vaginal dysbiosis.

Evidence & Sources

No sources recorded yet.