KPV guide
This KPV guide can state its central fact in one sentence: nobody has ever published giving KPV to a human being. No trial, no case report, no measurement of what it does in a person, by any route1317. FDA went looking for exactly that in 2026, across the literature, the trial registry and its own adverse-event databases, and wrote down that it found nothing12.
The short answer
- What it is: a three-amino-acid fragment from the tail end of a natural hormone called alpha-MSH.
- Human evidence: none of any kind1317.
- Animal evidence: real and reasonably consistent, in mice, rats and rabbits, all in induced-disease models56.
- Is it a tanning peptide? No. It shares an origin with melanotan II but the evidence says it does not work through the same receptors7.
- Toxicology: no acute, repeat-dose, genetic, reproductive or cancer study exists in any species1.
- In sport: not a named entry on the 2026 prohibited list, which is not the same as permitted4.
Why zero adverse-event reports is not reassuring
This is the part most worth getting right. FDA searched its adverse-event database and the medical literature for harms associated with KPV through December 2025 and retrieved no reports at all. It also searched a separate human-exposure database going back to 2004 and found no case where KPV had been administered.
That reads like a clean safety record until you notice the second half. There are no reports because there is no documented human exposure to produce them. FDA draws the conclusion itself: the potential safety risks of KPV in humans are unknown31. An empty column is not a low number.
The toxicology side is emptier still. FDA found no acute toxicity study, no repeat-dose study, no genetic toxicity study, no reproductive study and no cancer study — not in people, and not in animals either1. It also flags a risk it could not assess: even peptides as short as two amino acids can clump together, clumping is a known trigger for immune reactions, and no data exist either way for KPV1.
It is not a tanning peptide
KPV is the last three amino acids of alpha-MSH, the hormone melanotan II was built to mimic. That shared ancestry causes real confusion, and it is worth settling.
A 2003 study set out to separate the two. KPV reduced inflammation in mice, but it failed in the cell assay where the full hormone and melanotan II both worked, and it did not trigger the internal signal those compounds use. The authors concluded KPV is unlikely to act through melanocortin receptors at all, and probably works by blocking an inflammatory messenger instead7.
The practical consequence: KPV does not tan skin, and it does not inherit melanotan II’s record of harms. It also does not inherit any of its claims.
What the animal work actually shows
The foundational paper is a 2008 study that found KPV blocked two inflammatory signalling pathways in cultured cells at very low concentrations, and reduced colitis in mice given it in their drinking water56. A second laboratory reported the same direction of effect the same year, with treated mice recovering earlier and showing less inflammation in the colon.
There is a catch in the mechanism worth understanding. KPV gets into gut and immune cells through a transporter that carries short peptides — and that transporter is produced at low levels in a healthy colon and switched on by inflammation5. The route in depends on the disease being there.
Both colitis models are chemically induced acute injury in rodents, which is a model with a long history of not translating to human inflammatory bowel disease. And the nomination FDA actually evaluated was not for gut disease at all: it was for a 0.1 per cent topical cream12.
The delivery problem, which is the real story
Most of the KPV literature since 2010 is not about whether KPV works. It is about getting it anywhere useful.
Put under acid, KPV breaks down into a ring-shaped degradation product. Acid is what a stomach is81511. When one group packaged KPV into nanoparticles designed to survive the journey to the colon, the packaged form matched the effect of free KPV at a concentration twelve thousand times lower. That number is a measure of how much unprotected oral KPV is lost on the way.
On skin the problem is different and just as stark. In a laboratory permeation study, KPV left to diffuse across human skin did not cross at levels the instruments could detect at all. It only permeated once the skin was physically perforated with microneedles, and more still with an electrical current141. FDA cites this directly, noting it could limit KPV’s usefulness as a topical agent because it may never reach the living layers beneath the surface. A plain cream is exactly what was nominated.
The two claims that outrun the evidence
Antimicrobial. This rests on a single paper from 2000, testing two organisms in culture. In that paper KPV is reported pooled together with the full-length hormone throughout, so KPV’s own contribution cannot be separated out. An independent group in 2018 tested a close relative of KPV under a variety of conditions and found no antimicrobial activity at all1011. The null result is rarely mentioned next to the positive one.
Wound healing. The strongest result in the entire KPV literature is genuinely impressive: rabbit corneas scraped bare, treated with KPV drops, and all eight resurfaced by sixty hours while none of the placebo corneas had9. But a cornea is a transparent, blood-vessel-free surface that heals unusually fast, and the authors themselves say they do not know whether the effect belongs to KPV or to the whole parent hormone. There is no controlled skin wound-healing study to set beside it1314.
Newer claims about fat and liver metabolism come from 2026 experiments in cancer-derived cell lines, with no animal work behind them and certainly no human work[unverified].
Eighteen years of “future”
In 2008 a major review described KPV as an alternative for anti-inflammatory therapy, well suited to future treatment. In 2019 the same research tradition published a paper asking whether these peptides are future therapeutics for wound healing, and answered that they are promising future candidates1617.
FDA cites that 2019 paper for the proposition that clinical studies are still needed. The word doing the work in both reviews is future, and it has been doing that work for eighteen years without a single human study following it.
Where it stands with regulators
A pharmacy nominated KPV for compounding as a topical cream, then withdrew the nomination; FDA continued evaluating it anyway and proposed not adding it, citing the lack of any effectiveness or safety information in humans12. Its advisory committee met on 23 July 2026 and voted on both chemical forms2. An official committee outcome was not identified as of September 20, 2026.
In sport, KPV is not named on the 2026 prohibited list, and neither is any other melanocortin term. That is a meaningful negative, because the same list does name BPC-157 explicitly — so its authors were willing to name research peptides when they meant to. It is still not permission: the list covers substances no health authority has approved, the peptide section carries a similar-effect catch-all, and the list itself tells readers to check with their anti-doping organisation4.
The honest summary
KPV is not a compound with bad evidence. It is a compound with no human evidence, an interesting and internally consistent animal record, an unexplained mechanism1712, and a well-documented problem getting where it needs to go. Everything anyone says about what it does in a person is an extrapolation from a mouse, a rabbit eye or a dish of cells.
Where the rest of the detail lives
The interactive library on the homepage carries the fuller reference entry for KPV, including the amounts and handling notes it holds for every compound. That is general reference information, the same for every visitor.
References
These are the sources behind this page, listed so you can read them yourself rather than take our word for it. Animal and laboratory findings do not establish that something works or is safe in people. Doses and protocols shown on a study card are that study's research parameters, not recommendations. PepCaddie does not sell peptides and does not choose a dose for anyone; this is educational material and it does not replace a qualified healthcare professional.
The foundational colitis study
2008Animal studyNot human evidence
This is the paper nearly every gut claim about KPV traces back to. At nanomolar concentrations in cultured cells it blocked two inflammatory signalling pathways and reduced inflammatory messenger output, working through a transporter called PepT1 that carries short peptides into gut and immune cells. Given in drinking water, it reduced colitis in two mouse models. The authors’ own wording is that KPV might be a new therapeutic agent, not that it is one.
Limitation: The transporter the whole mechanism depends on is produced at low levels in a healthy colon and is switched on by inflammation, so the effect is conditional on the disease the model creates. The exact amount put in the drinking water is not in the retrievable record.
Cell-culture mechanism work plus two chemically induced colitis modelsView study: The foundational colitis study
Second colitis model, same year
2008Animal studyNot human evidence
Treated mice recovered earlier and regained more weight, with significantly less inflammatory infiltrate in the colon and lower tissue markers of inflammation. In a strain genetically lacking one melanocortin receptor, treatment rescued every animal in the group from death during induced colitis.
Limitation: The striking rescue result is in a genetically altered strain under an acute chemical injury, with no dose, route, duration or group size in the retrievable record. A large effect in a fragile artificial model tells you little about a person.
Two colitis models, including one in mice lacking a melanocortin receptorView study: Second colitis model, same year
The study that separates KPV from melanotan II
2003Animal studyNot human evidence
KPV reduced inflammatory cell accumulation in mice, but it failed in the cell-culture assay where the full hormone and melanotan II both worked, and it did not raise the signalling messenger those compounds use. The authors concluded that KPV is unlikely to work through melanocortin receptors at all, and more likely acts by blocking an inflammatory messenger instead. That is the cleanest evidence that KPV is not a melanotan and should not inherit melanotan II’s risks or its claims.
Limitation: Acute chemical peritonitis measured over hours is about immune cells moving, not about a chronic disease resolving. KPV’s effect is left mechanistically unexplained in the authors’ own hands.
Two induced peritonitis models plus cell-culture assaysView study: The study that separates KPV from melanotan II
Free KPV needed 12,000 times more than the protected form
2010Animal studyNot human evidence
Mice given KPV packaged into nanoparticles and protected through the gut were protected against colitis. The number that matters is the comparison: the packaged form worked at a concentration twelve thousand times lower than free KPV in solution for the same effect. The scientific point of the paper is how badly unprotected KPV survives the journey.
Limitation: A mouse model, and the intervention is really the delivery system. It is included because the delivery problem is routinely left out when oral KPV is discussed.
Controlled colitis model comparing free and encapsulated KPVView study: Free KPV needed 12,000 times more than the protected form
The strongest healing result, and it is a rabbit eye
2006Animal studyNot human evidence
The dose above is the amount used in this study. It is research information, not a recommended dose, and PepCaddie does not convert study doses into human doses.
Rabbit corneas scraped bare and then treated with KPV drops healed faster than vehicle at every time point, and at sixty hours all eight treated corneas had resurfaced while none of the placebo corneas had. It is the single most impressive in-life result in the KPV literature.
Limitation: It is a cornea: a transparent, blood-vessel-free surface that heals unusually fast and behaves nothing like skin. The authors themselves say they do not know whether the mechanism belongs to KPV or to the whole parent hormone.
Controlled study against vehicle after corneal surface injuryView study: The strongest healing result, and it is a rabbit eye
The only antimicrobial evidence
2000Laboratory or in-vitro studyNot human evidence
In culture, these peptides inhibited colony formation by one bacterium and reduced the viability of one yeast, at concentrations reaching down into the range found naturally in the body. Two organisms, in a dish. This single paper is the entire basis for KPV being described as antimicrobial.
Limitation: The paper reports KPV pooled with the full-length hormone throughout as alpha-MSH peptides, so KPV’s own potency cannot be separated out from the published abstract. No infection was treated in any animal.
Laboratory culture and cell-killing assaysView study: The only antimicrobial evidence
A published null result on the antimicrobial claim
2018Laboratory or in-vitro studyNot human evidence
An independent group tested a capped version of KPV and its modified analogues for antimicrobial activity under a variety of conditions and found none. The modified versions did survive digestive enzymes better, which was the point of making them. The null result is almost never mentioned alongside the positive one.
Limitation: The compound tested was a capped form rather than plain KPV, so it is not a strict attempt to reproduce the earlier positive result. It is still a published, independent, explicitly negative finding on a close relative.
Laboratory antimicrobial assays under several conditionsView study: A published null result on the antimicrobial claim
Proposed mechanism in human airway cells
2012Laboratory or in-vitro studyNot human evidence
In cultured human airway cells, KPV reduced inflammatory signalling and the release of two inflammatory messengers in a dose-dependent way. The proposed explanation is that KPV enters the nucleus and physically blocks an inflammatory switch from getting in.
Limitation: A single-author study in an immortalised cell line, published in a low-visibility journal with no assigned identifier, and the proposed mechanism does not appear to have been independently reproduced.
Cell-culture mechanism studyView study: Proposed mechanism in human airway cells
Signalling in human skin cells
2004Laboratory or in-vitro studyNot human evidence
This is the cell-culture work underneath the skin claims: human skin cells in a dish respond to KPV and to the related hormones. It establishes that the cells can respond, not that anything applied to skin reaches them.
Limitation: Cells bathed directly in the peptide. It says nothing about whether KPV crosses skin, which the permeation work suggests it largely does not.
Cell-culture signalling studyView study: Signalling in human skin cells
KPV did not cross skin without help
2017Laboratory or in-vitro studyNot human evidence
Left to diffuse on its own, KPV did not cross human skin at a level the instruments could detect at all. Permeation only appeared once the skin was physically perforated with microneedles, and rose further with an electrical current. FDA cites this directly, noting it could limit how useful KPV is as a topical agent because it may not reach the layers beneath the outer surface.
Limitation: Donated skin in a laboratory rig has no living metabolism and no blood flow carrying anything away, so it measures passage through a membrane rather than delivery to a target, and it shows no biological effect either way.
Laboratory permeation study comparing passive and assisted deliveryView study: KPV did not cross skin without help
It breaks down in acid
2015Laboratory or in-vitro studyNot human evidence
Put under acid, alkali or oxidising conditions, KPV broke down into a ring-shaped degradation product. Acid is what a stomach is, which is directly relevant to anything taken by mouth, and it is part of why the rest of the literature is full of attempts to package KPV rather than simply give it.
Limitation: A laboratory stability test designed to develop a measurement method, not a study of what happens in a digestive tract. It does not tell you how much survives in a person.
Laboratory stability study under stress conditionsView study: It breaks down in acid
A 2008 review calling it a future therapy
2008Narrative review
A thorough review from the group that has done much of this work, describing KPV as an alternative for anti-inflammatory therapy and noting its low expected production cost makes it suitable for future treatment. It is included here for what its date says: this was written in 2008, and no human study has followed in the eighteen years since.
Limitation: A review, and an advocacy one: it summarises the case for developing KPV rather than testing it. Reviews are not evidence, and this one inherits the limits of the animal work beneath it.
Narrative reviewView study: A 2008 review calling it a future therapy
Eleven years later, still a future candidate
2019Narrative review
The same research tradition, eleven years on, proposing these peptides as promising future candidates for wound healing and skin ulcers. FDA cites this very paper for the proposition that clinical studies are still needed. The word doing the work in both reviews is future.
Limitation: A review that argues a case. It is cited here as a marker of where the field places KPV, which is still before the first human study rather than after it.
Narrative reviewView study: Eleven years later, still a future candidate
FDA briefing document, Pharmacy Compounding Advisory Committee, July 2026: KPV-related bulk drug substances. U.S. Food and Drug Administration; 2026.
Official regulatory sourceChecked 2026-09-21
Read FDA's 2026 review of KPV for compounding at the sourceVoting questions, Pharmacy Compounding Advisory Committee meeting, 23 to 24 July 2026. U.S. Food and Drug Administration; 2026.
Official regulatory sourceChecked 2026-09-21
Read The advisory committee voting questions at the sourceCertain bulk drug substances for use in compounding that may present significant safety risks. U.S. Food and Drug Administration; 2026.
Official regulatory sourceChecked 2026-09-21
Read FDA's compounding listing for KPV at the sourceThe 2026 Prohibited List. World Anti-Doping Agency; 2026.
Official regulatory sourceChecked 2026-09-21
Read WADA's 2026 Prohibited List at the sourceDalmasso G, Charrier-Hisamuddin L, Nguyen HT, et al.. PepT1-mediated tripeptide KPV uptake reduces intestinal inflammation. Gastroenterology; 2008.
Animal studyPMID 18061177 · DOI 10.1053/j.gastro.2007.10.026Checked 2026-09-21
Read The foundational colitis study at the sourceKannengiesser K, Maaser C, Heidemann J, et al.. Melanocortin-derived tripeptide KPV has anti-inflammatory potential in murine models of inflammatory bowel disease. Inflammatory Bowel Diseases; 2008.
Animal studyPMID 18092346 · DOI 10.1002/ibd.20334Checked 2026-09-21
Read Second colitis model, same year at the sourceGetting SJ, Schiöth HB, Perretti M. Dissection of the anti-inflammatory effect of the core and C-terminal (KPV) alpha-melanocyte-stimulating hormone peptides. Journal of Pharmacology and Experimental Therapeutics; 2003.
Animal studyPMID 12750433 · DOI 10.1124/jpet.103.051623Checked 2026-09-21
Read The study that separates KPV from melanotan II at the sourceLaroui H, Dalmasso G, Nguyen HT, et al.. Drug-loaded nanoparticles targeted to the colon with polysaccharide hydrogel reduce colitis in a mouse model. Gastroenterology; 2010.
Animal studyPMID 19909746 · DOI 10.1053/j.gastro.2009.11.003Checked 2026-09-21
Read Free KPV needed 12,000 times more than the protected form at the sourceBonfiglio V, Camillieri G, Avitabile T, et al.. Effects of the COOH-terminal tripeptide alpha-MSH(11-13) on corneal epithelial wound healing: role of nitric oxide. Experimental Eye Research; 2006.
Animal studyPMID 16965771 · DOI 10.1016/j.exer.2006.07.014Checked 2026-09-21
Read The strongest healing result, and it is a rabbit eye at the sourceCutuli M, Cristiani S, Lipton JM, Catania A. Antimicrobial effects of alpha-MSH peptides. Journal of Leukocyte Biology; 2000.
Laboratory or in-vitro studyPMID 10670585 · DOI 10.1002/jlb.67.2.233Checked 2026-09-21
Read The only antimicrobial evidence at the sourceSongok AC, Panta P, Doerrler WT, et al.. Structural modification of the tripeptide KPV by reductive glycoalkylation of the lysine residue. PLOS ONE; 2018.
Laboratory or in-vitro studyPMID 29953505 · DOI 10.1371/journal.pone.0199686Checked 2026-09-21
Read A published null result on the antimicrobial claim at the sourceLand SC. Inhibition of cellular and systemic inflammation cues in human bronchial epithelial cells by melanocortin-related peptides. International Journal of Physiology, Pathophysiology and Pharmacology; 2012.
Laboratory or in-vitro studyPMID 22837805Checked 2026-09-21
Read Proposed mechanism in human airway cells at the sourceElliott RJ, Szabo M, Wagner MJ, et al.. Alpha-melanocyte-stimulating hormone, MSH 11-13 KPV and adrenocorticotropic hormone signalling in human keratinocyte cells. Journal of Investigative Dermatology; 2004.
Laboratory or in-vitro studyPMID 15102092 · DOI 10.1111/j.0022-202X.2004.22404.xChecked 2026-09-21
Read Signalling in human skin cells at the sourcePawar K, Kolli CS, Rangari VK, Babu RJ. Transdermal iontophoretic delivery of lysine-proline-valine (KPV) peptide across microporated human skin. Journal of Pharmaceutical Sciences; 2017.
Laboratory or in-vitro studyPMID 28343991 · DOI 10.1016/j.xphs.2017.03.017Checked 2026-09-21
Read KPV did not cross skin without help at the sourcePawar KR, Mulabagal V, Smith F, et al.. Stability-indicating HPLC assay for lysine-proline-valine (KPV) in aqueous solutions and skin homogenates. Biomedical Chromatography; 2015.
Laboratory or in-vitro studyPMID 25298219 · DOI 10.1002/bmc.3347Checked 2026-09-21
Read It breaks down in acid at the sourceBrzoska T, Luger TA, Maaser C, et al.. Alpha-melanocyte-stimulating hormone and related tripeptides: biochemistry, antiinflammatory and protective effects in vitro and in vivo, and future perspectives for the treatment of immune-mediated inflammatory diseases. Endocrine Reviews; 2008.
Narrative reviewPMID 18612139 · DOI 10.1210/er.2007-0027Checked 2026-09-21
Read A 2008 review calling it a future therapy at the sourceBöhm M, Luger T. Are melanocortin peptides future therapeutics for cutaneous wound healing?. Experimental Dermatology; 2019.
Narrative reviewPMID 30661264 · DOI 10.1111/exd.13887Checked 2026-09-21
Read Eleven years later, still a future candidate at the source