01 What is KPV?
In plain English.
KPV is one of the smallest peptides anyone bothers to study, just three [amino acids](/glossary "Amino acid: The building blocks of proteins. A peptide is a short chain of them linked together.") long: lysine, proline, valine. It is the C-terminal tail of α-melanocyte-stimulating hormone (α-MSH), a hormone the body makes that does two main things: it darkens skin pigment (via the N-terminal end of the molecule) and damps down inflammation (a property concentrated at the C-terminal end). KPV is essentially "α-MSH with the pigment-driving part removed", which is why researchers have been interested in it for almost thirty years.
Being only three residues long has a useful side-effect: KPV is small enough to be absorbed intact from the gut via the PepT1 transporter, the same channel that ferries di- and tri-peptides from digested food. That is why most of the serious preclinical work on KPV has involved giving it orally, often in drinking water, to mice with experimentally induced colitis. It is sold online as a research chemical, sometimes in oral, injectable and topical formulations, but no version of it is an approved medicine in any country.
02 How it works
The simple version, then the science.
KPV calms inflammation in two ways. First, it appears to enter immune and gut-lining cells via the PepT1 transporter, where it interferes with the NF-κB and MAPK signalling pathways, the two main switches the body throws to mount an inflammatory response, and reduces output of pro-inflammatory cytokines. Second, like its parent hormone α-MSH, it has some antimicrobial activity against bacteria and fungi in lab assays. The pigment-driving N-terminal sequence of α-MSH is absent, so KPV does not darken skin.
Go deeper · the proposed mechanism
KPV is α-MSH(11-13): Lys-Pro-Val. Its uptake into intestinal epithelial cells and immune cells is mediated by PepT1 (SLC15A1), a proton-coupled oligopeptide transporter that is normally restricted to the small intestine but becomes upregulated in colonic epithelium during IBD, conveniently concentrating KPV at the site of inflammation. Once intracellular, KPV inhibits IκB phosphorylation and NF-κB nuclear translocation, dampens p38 MAPK signalling, and reduces TNF-α, IL-6, IL-8 and IFN-γ output in stimulated epithelial and T cells. Some KPV activity is also reported to be melanocortin-receptor independent, i.e. it does not require MC1R, MC3R or MC5R, which distinguishes its mechanism from longer α-MSH fragments and from melanocortin-receptor-targeted clinical compounds.
03 What it's used for
Each use graded by how strong the evidence actually is.
- PreclinicalInflammatory bowel disease (animal models)The strongest signal. Oral KPV reduced colitis severity in DSS- and TNBS-induced mouse models (Kannengiesser 2008; Dalmasso 2008). Reproducible across labs, but entirely preclinical, no human IBD trials of the KPV tripeptide exist.
- PreclinicalColitis-associated cancer (mouse model)A 2016 study (Viennois et al.) reported KPV reduced colitis-associated tumour development in mice via PepT1. A single preclinical signal; not a human result.
- AnecdotalGeneral "gut healing" and IBD self-managementPromoted in biohacker and bodybuilding circles as an oral anti-inflammatory for gut symptoms, often alongside BPC-157. No controlled human evidence supports this use.
- AnecdotalSkin inflammation and topical wound healingSold in topical research preparations on the basis of α-MSH-family anti-inflammatory biology. Human data is absent.
04 What the evidence says
The preclinical signal for KPV is genuinely interesting and reproducible, multiple groups (Kannengiesser and Luger's lab in Münster; Merlin's group in Atlanta) have independently shown that oral KPV reduces colitis severity in chemically induced mouse models, with a coherent mechanism (PepT1-mediated uptake, NF-κB/MAPK inhibition, reduced cytokine output). The 2008 Brzoska review in Endocrine Reviews maps the broader case for α-MSH-derived peptides as anti-inflammatories. Where the story stops short is humans: there are no published controlled clinical trials of the KPV tripeptide itself as a therapeutic for IBD or anything else. The melanocortin-pathway drug furthest advanced clinically is resomelagon (AP1189), a different, biased melanocortin-receptor agonist in Phase 2 development by SynAct Pharma, not KPV. Honest read: a coherent preclinical IBD signal, mechanistic plausibility, and approximately zero human evidence for KPV as a therapeutic.
05 Dosing & administration
Reported in the literature, information not advice.
Because there is no approved human protocol for KPV, no safe or effective dose has been established. The most-cited animal work used oral KPV in drinking water at low microgram-per-day quantities in mice, figures that do not translate directly to humans. Online research-chemical communities describe oral capsules, subcutaneous injection, intranasal sprays and topical creams across a wide milligram range, but none of these regimens are supported by clinical evidence and the purity of vendor-supplied KPV is not regulated. A qualified clinician should be consulted before considering any peptide.
06 Side effects & safety
Long-term safety in humans is unknown, there are no human trials of KPV. The published animal toxicity profile is reasonably benign at the doses studied, and as a fragment of a hormone the body already produces, severe acute toxicity is not the leading concern. The honest concerns are different: products sold as "KPV" are unregulated research chemicals, so identity, purity and dose-by-dose consistency are not guaranteed; oral formulations may not survive gut transit in the form they were intended; and "anti-inflammatory" is not a neutral property, broad immune modulation can in principle dampen useful inflammatory responses too. People who are pregnant, breastfeeding, immunocompromised, have active infections or take other medicines should be especially cautious. Most importantly: treating IBD or any other inflammatory disease with an unapproved research chemical instead of established therapy is a poor trade.
07 Where to buy (research use only)
Vetted on quality and transparency, not an endorsement to use.
08 Legal & regulatory status
- UKNot licensed as a medicine. Sold only as a "research chemical", not for human use.
- USNot FDA-approved. Not on the FDA's list of bulk substances permitted for compounding.
- EU / AUS / CANNo approved human medicine containing KPV. Sale for human use is unlawful in most jurisdictions; "research use only" framing is standard.
- Sport (WADA)
09 Clinical studies & research
Primary sources. Read the science yourself.