Compare Peptides

Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.

Popular comparisons

LL-37

Cathelicidin, Human Cathelicidin Antimicrobial Peptide

Unregulated
Immune & Antimicrobial

KPV

Lys-Pro-Val, α-MSH C-terminal tripeptide

Pending PCAC
Anti-Inflammatory & Healing
Overview

The only human cathelicidin antimicrobial peptide, LL-37 is a 37-amino-acid peptide naturally produced by immune cells, epithelial cells, and barrier tissues. It plays a critical role in innate immunity by directly killing bacteria, viruses, and fungi, while also modulating inflammatory responses. Increasingly studied for chronic infections, biofilm disruption, and immune regulation.

A tripeptide (Lysine-Proline-Valine) derived from the C-terminus of alpha-MSH (melanocyte-stimulating hormone). Has potent anti-inflammatory properties and is being studied for inflammatory bowel conditions and wound healing.

Mechanism of Action

Disrupts microbial membranes through electrostatic interaction with negatively charged bacterial surfaces, creating pores that kill pathogens. Also modulates immune responses by recruiting immune cells, promoting wound healing, and disrupting bacterial biofilms. Acts as a bridge between innate and adaptive immunity.

Inhibits NF-κB signaling and pro-inflammatory cytokine production. Crosses the intestinal epithelium to directly suppress inflammation locally. Anti-microbial properties have also been demonstrated in vitro.

Common Uses
  • Immune system support
  • Chronic infection management
  • Biofilm disruption (Lyme, SIBO)
  • Wound healing
  • Upper respiratory infection support
  • Inflammatory bowel disease (IBD) support
  • Wound healing and skin conditions
  • General anti-inflammatory protocols
  • Gut health optimization
Known Risks
  • Injection site reactions (pain, redness)
  • Potential autoimmune activation at high doses
  • Limited human clinical data for therapeutic use
  • Overexpression linked to psoriasis and rosacea in some contexts
  • Very limited human clinical data
  • Optimal delivery method not established
  • Injection vs. oral bioavailability differences not fully characterized
  • Long-term safety unknown
Regulatory Status
Unregulated

Not FDA-approved as a therapeutic. LL-37 is an endogenous human peptide being studied in clinical trials for wound healing and infection. Some compounding pharmacies have offered it, but it has no formal FDA category for compounding. Research is ongoing for topical wound applications.

Pending PCAC

Removed from FDA 503A Category 2 effective April 22, 2026. Scheduled for PCAC review on July 23, 2026 for wound healing and inflammatory conditions. Compounding not yet authorized — status is in regulatory gray zone pending PCAC recommendation.

PCAC: July 23, 2026

This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.