KPV vs LL-37
A neutral, side-by-side comparison of two healing & recovery peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
KPV
KPV is a C-terminal tripeptide fragment (Lys-Pro-Val) of alpha-melanocyte stimulating hormone (α-MSH). Despite its small size — just three amino acids — it retains the anti-inflammatory core activity of its parent molecule without the melanogenic effects. It is one of the most researched peptides for gut inflammation, IBD, and intestinal permeability, with the ability to act locally in the gut when administered orally.
Full profileLL-37
LL-37 is the only human cathelicidin — a host defense peptide produced by neutrophils, epithelial cells, and macrophages in response to infection and inflammation. It functions simultaneously as a broad-spectrum antimicrobial agent and an immune-modulatory signaling molecule. Research interest has expanded dramatically since COVID-19 studies linked low LL-37 levels to severe outcomes, and gut health research identified it as a key regulator of intestinal barrier integrity.
Full profile| KPV | LL-37 | |
|---|---|---|
| Category | Healing & Recovery | Healing & Recovery |
| Also known as | Lys-Pro-Val, Alpha-MSH C-terminal tripeptide | Cathelicidin LL-37, hCAP-18 C-terminal fragment, CRAMP (murine equivalent) |
| Evidence | Research-stage | Research-stage |
| Dosing range | 250mcg–1000mcg mcg, Once or twice daily | 100mcg–500mcg mcg, Daily or 3–5x weekly |
| Administration | Subcutaneous injection, Oral (encapsulated — for gut-specific delivery), Intranasal | Subcutaneous injection, Intranasal (for respiratory applications), Topical (wound care) |
| Key side effects | Generally well-tolerated, Mild injection site irritation, Transient headache (uncommon), No melanogenic effects (does not cause tanning unlike full α-MSH) | Injection site redness and irritation (common — pro-inflammatory at injection site), Transient flu-like symptoms (immune activation), Local induration, High doses may be cytotoxic — dose-response curve is non-linear |
| Cited sources | 3 references | 3 references |
Key differences
- Administration: KPV — Subcutaneous injection, Oral (encapsulated — for gut-specific delivery), Intranasal; LL-37 — Subcutaneous injection, Intranasal (for respiratory applications), Topical (wound care).
- Frequency: KPV is typically Once or twice daily; LL-37 is Daily or 3–5x weekly.
How each works
KPV
KPV exerts anti-inflammatory effects through melanocortin receptor-independent mechanisms as well as via MC1R and MC3R activation. It downregulates NF-κB, inhibits pro-inflammatory cytokines (TNF-α, IL-1β, IL-8), and reduces neutrophil infiltration in colonic tissue. Uniquely for a peptide, KPV is acid-stable enough to survive gastric transit and reach the intestinal mucosa intact, making oral delivery viable for gut-targeted applications — a significant advantage over most injectable-only peptides.
LL-37
LL-37 exerts antimicrobial activity by disrupting bacterial membranes via electrostatic interaction with negatively charged lipopolysaccharide — effective against gram-positive and gram-negative bacteria, fungi, and enveloped viruses including SARS-CoV-2 in vitro. Beyond direct antimicrobial action, LL-37 modulates innate immunity through TLR4 signaling, promotes wound healing via EGFR and FPRL1 receptor activation, and has demonstrated anti-biofilm activity against P. aeruginosa and S. aureus. Vitamin D is the primary driver of endogenous LL-37 production.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.