Colitis and gut inflammation
In two mouse models of colitis, KPV-treated mice recovered sooner, regained more weight and had less colon inflammation.3
Peptide Guide · Gut and inflammation
KPV
Lys-Pro-Val, an alpha-MSH fragment
KPV is just three amino acids, small enough to ride into gut cells on a transporter built for digested food, one that inflammation itself switches on.
Free to join · One email when peptide care opens · Most lab results in 3–5 business days
- Studied for
- Gut and skin inflammation
- Evidence
- Early research
- Taken as
- Compounded as oral capsule, injection or cream, as prescribed; human routes untested
KPV, in short
KPV is a three-amino-acid peptide (lysine, proline, valine) taken from the tail of alpha-MSH, a hormone that calms inflammation. Gut and immune cells absorb it through a transporter called PepT1, and inside the cell it turns down NF-κB, a master inflammation switch. It is studied for colitis and skin inflammation, so far in cell and animal research.
Medically reviewed by Robert Lufkin, MD (opens in a new tab)
Chief Medical Officer, Vitals Vault · Updated · 11 sources
Before you consider KPV
How does KPV work?
KPV acts inside the cells that line the gut, where gut inflammation starts.
Gets into gut cells
A carrier in the gut lining pulls KPV inside the cell, which is why it can work when swallowed.2
Quiets the inflammation switch
Inside the cell, it turns down the main switch that tells the cell to make inflammatory signals.2
Calms the tissue
Cells send fewer inflammatory signals, and fewer immune cells crowd into the colon.23
KPV benefits: what it is studied for
KPV’s research is focused and consistent. All of it so far comes from cell and animal studies.
- Animal study01
- Animal study02
Ulcerative colitis, taken by mouth
Swallowed in gut-targeted nanoparticles, KPV eased ulcerative colitis in mice in a 2017 study.8
- Animal study03
Eye surface healing
Topical KPV fully healed all 8 rabbit corneal wounds within 60 hours.6
- Animal study04
Skin inflammation
KPV calmed allergic skin reactions in mice, one reason it is studied for inflamed skin.5
What the research shows
Early research- 1 · Cells in a lab Studied
Turns down inflammation switches in gut and immune cells at very low concentrations.2
Shows a mechanism
- 2 · Animals Studied
Eased colitis in mouse models, including when swallowed, and healed rabbit corneal wounds.386
Shows an effect in a body
- 3 · PeopleNot yet
No controlled human trials yet. In July 2026, FDA found no clinical studies of KPV in people.1
Shows it works in people
The full guide to KPV
How a tanning hormone gave up three amino acids
The hormone that tans your skin also quiets your immune system. Alpha-MSH, alpha-melanocyte-stimulating hormone, is a 13-amino-acid peptide famous for switching on pigment. By the early 2000s, researchers in Münster had shown it does something less visible, turning down the inflammatory signals of monocytes, macrophages and dendritic cells.
Then came the surprise. The anti-inflammatory message did not need the whole hormone. Its last three amino acids, lysine, proline and valine, positions 11 to 13, could bind the same receptor on immune cells and change how they behave. A rabbit eye study later put it plainly, describing the effective message sequence of alpha-MSH as residing in that tail.
Those three letters, K, P and V, became the name. KPV is among the smallest molecules discussed as a peptide therapy, three amino acids long, about as short as a peptide gets.
Its size is what makes it interesting. A molecule that small can slip into gut cells through a transporter meant for digested food, and that transporter behaves in a way that makes KPV unusually well matched to the inflamed gut.5632
How KPV works inside gut and immune cells
Inflammation inside a cell runs through a handful of master switches. The best known is NF-κB, a protein that, once activated, turns on dozens of genes for inflammatory cytokines. In 2008, a team in Atlanta showed that KPV, at nanomolar concentrations, blocked the activation of NF-κB and of MAP kinase, another inflammatory pathway, in human intestinal cells and human T cells.
The same work showed how KPV gets in. PepT1 is a transporter that normally carries di- and tripeptides from digested protein into the cells of the small intestine. KPV is a tripeptide, so PepT1 handles it like food and carries it inside, where it can reach those switches.
Alpha-MSH’s own story offered a second route. Immune cells carry melanocortin-1 receptors, MC1R, and both alpha-MSH and KPV can bind them. But a German team found that KPV still protected mice whose MC1R did not work. In those mice, KPV rescued every treated animal from death during chemically induced colitis.
So KPV does not need a working MC1R for at least part of its effect, and PepT1 is the route that carries it inside gut and immune cells. Either way, the result in these studies was fewer pro-inflammatory cytokines and fewer immune cells crowding into the colon wall.235
Inflammation opens the door
PepT1, the transporter that carries KPV into cells, is found mostly in the small intestine. In a healthy colon it is present only at low levels. During inflammatory bowel disease, the colon switches it on.
That raises an appealing possibility: a drug that enters cells through PepT1 might reach inflamed colon more than healthy colon, as if the inflammation builds the door the treatment walks through. Nobody has directly measured KPV uptake in inflamed versus healthy colon, but in mice, oral KPV in drinking water did reduce colitis, and it worked through PepT1.
The same door has a darker side. In a 2016 mouse study, animals engineered to overproduce PepT1 in the gut lining developed larger colitis-associated tumors and a greater tumor burden, while mice lacking PepT1 developed fewer and smaller ones. Human colorectal tumors also showed more PepT1. Yet KPV prevented tumor formation in normal mice, and in mice without PepT1 it had no effect at all.
This is a hypothesis built on mouse work, and it has not been tested in people. But it reframes KPV in a useful way. Its strongest asset may be targeting, a tiny molecule that concentrates its effect where inflammation has opened a transporter, which is also why it is studied so specifically for the colon.24
KPV for colitis: what the mouse studies found
Two independent groups tested KPV in colitis in 2008, using different models. The Atlanta team used two chemical models, DSS and TNBS, which damage the colon lining in different ways. Mice given KPV in their drinking water had less colitis and lower expression of inflammatory cytokines in the colon.
A German team used DSS colitis plus a second model, transfer colitis, in which T cells moved into a mouse drive the inflammation. In DSS colitis, KPV-treated mice recovered earlier, regained significantly more weight and had fewer inflammatory cells in the colon, and a marker of neutrophil activity, myeloperoxidase, fell significantly. In transfer colitis, treated mice also recovered, regained weight and showed less inflammation under the microscope.
Agreement between separate labs, models and routes is the strongest thing KPV has going for it. The weakness is the same one most gut peptides share. Every one of these results comes from mice, and mouse colitis only approximates human disease.
The measures themselves are worth understanding. Weight loss is how a mouse with colitis shows it is sick, so weight regain is a rough, whole-animal sign of recovery. Fewer inflammatory cells in the colon wall and lower cytokine levels show the same recovery under a microscope. KPV moved all of these in the right direction.23
Getting KPV where it is needed
A three-amino-acid peptide taken by mouth faces a long trip. Digestive enzymes, stomach acid and the sheer length of the intestine all stand between a capsule and the inflamed colon. Researchers who believe in KPV have spent years on delivery.
In 2017, the Atlanta group loaded KPV into nanoparticles coated with hyaluronic acid, a coating that helped the particles reach colon lining cells and macrophages. Packed into a gel that released them in the colon, the particles delivered KPV into those target cells. In mice with colitis, they sped healing of the colon lining, lowered the inflammatory cytokine TNF-alpha, and outperformed the same particles without the coating.
The particles were nontoxic to intestinal cells in the lab. For anyone considering KPV today, the lesson is practical. In mice, how KPV reached the colon changed how well it worked, and compounded oral capsules have not been tested the same way.
There is a quieter point here too. The nanoparticle work was done by the same Atlanta group that first described KPV’s route through PepT1, a decade of follow-up from one lab. That is a sign of sustained interest, and also a reminder that independent replication in people is the step still missing.8
KPV for skin and the eye
Before the gut, KPV was a skin story. In mice with contact hypersensitivity, the immune reaction behind allergic rashes from things like nickel or poison ivy, both alpha-MSH and KPV inhibited the reaction when given by injection or applied to the skin. They also induced lasting tolerance to the trigger.
The researchers traced this to immune cells called dendritic cells. Alpha-MSH lowered their production of inflammatory cytokines such as IL-1, IL-6 and TNF-alpha, raised the calming cytokine IL-10, and reduced the surface molecules dendritic cells use to activate T cells.
The eye adds another data point. In a 2006 rabbit study, topical KPV sped the healing of corneal surface wounds, and all eight treated corneas had fully re-covered within 60 hours. Blocking nitric oxide production blunted the effect, suggesting nitric oxide is part of how KPV helped the eye surface repair itself.
Compounding pharmacies make KPV creams for skin goals, but no published trial has tested topical KPV on human skin. The skin evidence is a mouse allergy model and a rabbit eye, both encouraging, both a long way from a person with eczema or psoriasis.56
KPV vs BPC-157 for gut health
KPV and BPC-157 both come up constantly in gut conversations, and the research on them comes at the gut from different directions. BPC-157 is a 15-amino-acid peptide its researchers describe as a natural protectant in gastric juice, studied in animals mainly for protecting the gut lining and its small blood vessels.
KPV is studied almost entirely as an anti-inflammatory. It enters gut and immune cells and turns down the switches that drive inflammatory cytokines. The BPC-157 studies lean toward the lining and its blood supply, the KPV studies toward immune signals, though KPV nanoparticles also sped healing of the lining in mice. Those are research emphases, not proven clinical roles.
None of the studies cited here compares them or tests them together. Both rest mainly on animal research, and both are now available from 503A pharmacies with a prescription. No evidence yet tells anyone how to choose between them for a human gut condition, so the more useful conversation with a clinician is about what is driving the problem.2379
What we know about KPV in people
The human evidence for KPV is indirect. Human intestinal cell lines and human T cells respond to it in the lab, PepT1 is switched on in the colon during inflammatory bowel disease, and human colorectal tumor tissue carries more of it. Those findings make the mouse results plausible in people without proving them.
What does not yet exist is a published controlled trial of KPV in people with colitis, irritable bowel symptoms or skin disease. FDA’s April 2026 compounding page made the same point, noting no human exposure data.
For someone with inflammatory bowel disease, that gap carries real weight. Approved treatments have trial data in people, and KPV does not. Nothing in the mouse record shows that KPV is a safe or effective addition to that care, so proven treatment stays the foundation.
The size of the gap is easy to measure. Two 2008 mouse papers, one rabbit eye study, a mouse cancer model and a nanoparticle study make up the core of the record. That is a coherent body of work from a small number of labs, and it is the kind of foundation that usually comes before a first human trial.2410
KPV side effects and safety
The mouse study abstracts do not describe harms, though they were not built to look for them, and in MC1R-deficient mice KPV rescued every treated animal from death during colitis. KPV-loaded nanoparticles were nontoxic and compatible with intestinal cells in the lab. KPV is also a sequence from a hormone your body already makes, but that does not show that taking it as a drug is safe, and FDA has said there is too little information to judge.
The unknowns are human safety, long-term use and quality. Human safety trials have not been published. As with every compounded peptide, the difference between a licensed 503A pharmacy and a vial sold online for research use is the difference between a regulated product and an unknown one.
The PepT1 cancer study deserves a careful reading. It found that high PepT1 promoted tumors in mice, while KPV itself prevented them. That points to the transporter as the risk factor, though anyone with a personal history of colorectal cancer should talk to their clinician first.
Others who should check first include anyone with diagnosed inflammatory bowel disease, who should keep their current treatment, anyone pregnant or breastfeeding, and anyone with kidney or liver disease.38410
Labs that give context around KPV
hs-CRP, high-sensitivity C-reactive protein, is made by the liver in response to inflammation anywhere in the body. It gives a clinician general context on whole-body inflammation, but it is nonspecific and has not been validated as a marker of response to KPV.
ALT, alanine aminotransferase, is a liver enzyme that rises when liver cells are stressed, and eGFR estimates how well the kidneys filter. Neither is a KPV-specific marker, and no KPV monitoring protocol exists. They give a clinician general baseline context on liver and kidney health.
Vitals Vault builds peptide care around that sequence. A blood panel at Quest Diagnostics comes first, a licensed clinician reviews your results and history and decides whether KPV fits, and the course ends with a retest of the same markers.10
Where KPV stands in 2026
On October 29, 2026, NCPA reported that FDA granted enforcement discretion allowing 503A compounding pharmacies to prepare KPV, along with five other peptides, for individual patients with a prescription. There is no end date, and final rulemaking is pending.
KPV is still not an FDA-approved drug for any condition. A prescription from a licensed clinician, filled by a 503A pharmacy, is now the regulated route.
Vials sold online as research chemicals are not made for people and are not covered by FDA’s October 2026 policy. The policy applies to prescriptions for individual patients filled by licensed 503A pharmacies.91011
What this means for you
KPV is the anti-inflammatory tail of a skin hormone, small enough to ride into gut cells on a transporter that inflammation itself switches on. In mice it consistently calmed colitis, worked by mouth and prevented colitis-linked tumors. In people, it has not yet been tested in a published trial.
If gut inflammation is your reason for looking at KPV, the first question is what is inflaming the lining. Infections, food triggers, medicines and diagnosed bowel disease each call for different care. Once that is clear, a clinician can talk through whether KPV is worth considering, knowing that routine labs cannot prove whether it helped.234
What to expect with KPV
A responsible start includes a clear picture of what is driving your gut inflammation, a baseline blood panel including hs-CRP, and a clinician’s decision on whether KPV fits and in what form. The course ends with a retest of the same markers.
On timing, the only data come from animals. Mice with colitis recovered earlier and regained weight over the course of the studies, and rabbit corneas healed within days. How those time frames translate to people has not been studied, so track symptoms and markers rather than expecting a fixed date.36
Key KPV studies
Luger et al., 20035
Review of experimental studies · Immune cells; mice with allergic skin reactions
Alpha-MSH and KPV calmed dendritic cells and blocked contact hypersensitivity
Limits: Animal and cell work
Bonfiglio et al., 20066
Animal study · Rabbits with corneal abrasions
Topical KPV sped corneal healing; 8 of 8 treated corneas healed by 60 hours
Limits: Rabbits; eye surface only
Dalmasso et al., 20082
Cell and mouse study · Human gut and T cells; mice with DSS and TNBS colitis
KPV enters cells via PepT1, blocks NF-κB, and reduced colitis when given by mouth
Limits: Mice, not people
Kannengiesser et al., 20083
Mouse study · Mice with DSS and transfer colitis, including MC1R-deficient mice
Faster recovery, weight regain, less colon inflammation; rescued all MC1R-deficient mice
Limits: Mice, not people
Viennois et al., 20164
Mouse study plus human biopsies · Mice with colitis-associated cancer; human colon tissue
KPV prevented tumors, but only in mice with PepT1
Limits: Mouse cancer model
Xiao et al., 20178
Mouse study · Mice with experimental colitis
Targeted KPV nanoparticles sped mucosal healing and lowered TNF-alpha
Limits: Special delivery system, not a standard capsule
KPV myths and evidence
A three-amino-acid peptide is too small to do anything
At nanomolar concentrations, KPV blocked NF-κB and MAP kinase signaling in human gut and immune cells, and it reduced colitis in several mouse models.23
KPV gets destroyed in the gut, so it only works by injection
Its small size is an advantage here. The gut transporter PepT1 carries tripeptides like KPV into cells, and KPV given in drinking water reduced colitis in mice.2
KPV is just a weaker form of alpha-MSH and works the same way
KPV can bind the same immune receptor, MC1R, but it still protected mice whose MC1R did not work, so at least part of its effect runs through other routes such as PepT1.35
KPV is proven for IBD
Not in people. The evidence comes from cells and mice. Anyone with inflammatory bowel disease should keep their prescribed treatment and discuss KPV with the clinician who manages it.310
How is KPV taken?
Compounded KPV is most often made as an oral capsule for gut goals, since PepT1 absorbs it in the intestine. Injections and creams are also made. Your prescriber chooses the form and dose.2
KPV dosage
There is no FDA-approved KPV dose, and no human dose has been published. In its July 2026 review, FDA found no clinical studies of KPV in people for any form, including the creams and gels that were nominated for compounding. Your clinician sets the form, dose and schedule, if any.1
Typical KPV dosage
No human dose of KPV has been published. FDA reviewed KPV for compounding in July 2026 and found no clinical studies or other human exposure data, by mouth, on the skin or by injection. The doses in the research come from laboratory and animal models, which do not translate to people. A clinician would have to decide any use and dose.
Already have a prescribed dose? The peptide dosage calculator turns it into the units to draw on an insulin syringe.
No dose has been published from studies in people yet, so there is no typical dose to show. A prescribing clinician decides whether KPV fits and how it is given.
Is KPV right for you?
A clinician makes the call. These are the questions they will ask first.
It may suit
- Adults with ongoing gut inflammation who are already working with a clinician on the cause
- People who want inflammation markers measured before and after
- Skin inflammation goals under supervision
Talk to a clinician first if you are
- A diagnosed inflammatory bowel disease (keep your current treatment)
- Pregnant or breastfeeding
- Living with kidney or liver disease
Vitals Vault peptide care starts with a blood panel and a licensed clinician, and ends with a retest.
Get early access to peptide careFind what is inflaming the gut
What else moves the same system
- 01Find the driverInfections, food triggers and medicines such as NSAIDs are common causes worth ruling out with a clinician.
- 02Feed the liningA wide range of plant fibers feeds the bacteria that make butyrate, the main fuel for colon cells.
- 03Track hs-CRPA blood marker of inflammation across the whole body, useful for seeing the bigger picture over time.
- 04Keep your careIf you have a diagnosed bowel disease, KPV sits alongside your treatment, never in place of it.
Labs to check with KPV
A blood test before you start and a retest after shows what actually changed for you. It is how Vitals Vault approaches every treatment.
- TestA baseline panel at Quest Diagnostics.
- DecideA licensed clinician reviews your history and results.
- RetestThe same markers again, side by side.
Is KPV FDA approved?
No. Since October 29, 2026, FDA allows 503A pharmacies to compound KPV for individual patients with a prescription, under enforcement discretion, while the final rule is pending.9
What FDA’s decision meansKPV timeline
2003
Review shows alpha-MSH and KPV calm immune cells and allergic skin reactions in mice.5
2006
Topical KPV speeds corneal wound healing in rabbits.6
2008
Two studies show KPV is absorbed through PepT1 and reduces colitis in mice.23
2016
KPV prevents colitis-associated tumors in mice, but only when PepT1 is present.4
2017
Hyaluronic acid nanoparticles deliver KPV to inflamed colon cells in mice.8
April 2026
FDA’s compounding safety page lists KPV as a nominated bulk substance and notes how little human safety data exists.10
July 2026
FDA’s Pharmacy Compounding Advisory Committee votes to recommend adding KPV to the 503A bulks list.9
October 29, 2026
FDA grants enforcement discretion, so 503A pharmacies can compound KPV with a prescription. No end date; final rule pending.9
KPV questions
What is KPV peptide used for?
KPV is studied for calming inflammation, mainly in the gut, including colitis, and in the skin. It is not FDA-approved to treat any condition.
What are the benefits of KPV?
In mouse studies, KPV reduced colitis, worked when taken by mouth and prevented colitis-linked tumors, and treated mice recovered and regained weight. It lowers inflammatory signals in gut and immune cells. Human trials have not been published.
What does KPV stand for?
Its three amino acids, in one-letter code: lysine (K), proline (P) and valine (V). They are the last three amino acids of the hormone alpha-MSH.
How does KPV work?
Gut and immune cells absorb it through the PepT1 transporter. Inside, it blocks NF-κB and MAP kinase, two of the main switches for inflammation, so cells release fewer inflammatory cytokines.
Should KPV be taken orally or injected?
Oral capsules are the most common form for gut goals, because the intestine absorbs KPV directly through PepT1. Your prescriber chooses the form.
What are the side effects of KPV?
Mouse study abstracts do not describe harms, but human safety trials have not been published. Product quality varies outside pharmacies, and people with bowel disease should keep their prescribed treatment.
What is the KPV dosage?
There is no FDA-approved KPV dose, and no human dose has been published: FDA found no clinical studies of KPV in people in its July 2026 review. Your clinician sets the form, dose and schedule, if any.
KPV vs BPC-157: which is for the gut?
Both are studied for the gut, in different ways. KPV is a three-amino-acid piece of alpha-MSH that turns down inflammation inside gut and immune cells. BPC-157 is described as a protective peptide from gastric juice and is studied for protecting the gut lining and its blood vessels. No study cited here has compared them.
Is KPV FDA approved?
No. KPV is not FDA-approved for any use. Since October 29, 2026, FDA allows 503A compounding pharmacies to prepare it for individual patients with a prescription, under enforcement discretion, while final rulemaking is pending.
Is KPV legal in the US?
A licensed prescriber can now order compounded KPV from a 503A pharmacy for a specific patient. Vials sold online as "research use only" are not made for people and are not covered by FDA’s October 2026 policy.
Can I get KPV through Vitals Vault?
Vitals Vault is opening clinician-led peptide care that starts with a blood test. Join the peptides waitlist to hear first. A licensed clinician reviews your history and labs and decides whether KPV is right for you.
Peptides, prescribed and measured
Vitals Vault is opening peptide care that starts with your blood work, is prescribed by licensed US clinicians and ends with a retest. Join the waitlist to hear first.
- Prescription only
- Licensed US clinicians
- Quest Diagnostics labs
Keep reading
Full Peptide Guide
Sources
- 1. FDA. Briefing document, Pharmacy Compounding Advisory Committee meeting, July 23 to 24, 2026: KPV-related bulk drug substances (opens in a new tab)
- 2. Dalmasso G, et al. PepT1-mediated tripeptide KPV uptake reduces intestinal inflammation. Gastroenterology. 2008 (opens in a new tab)
- 3. Kannengiesser K, et al. Melanocortin-derived tripeptide KPV has anti-inflammatory potential in murine models of IBD. Inflamm Bowel Dis. 2008 (opens in a new tab)
- 4. Viennois E, et al. PepT1 in colitis-associated cancer and benefits of the tripeptide KPV in a murine model. Cell Mol Gastroenterol Hepatol. 2016 (opens in a new tab)
- 5. Luger TA, et al. New insights into the functions of alpha-MSH and related peptides in the immune system. Ann N Y Acad Sci. 2003 (opens in a new tab)
- 6. Bonfiglio V, et al. Effects of the COOH-terminal tripeptide alpha-MSH(11-13) on corneal epithelial wound healing: role of nitric oxide. Exp Eye Res. 2006 (opens in a new tab)
- 7. Sikiric P, et al. Stable gastric pentadecapeptide BPC 157 in trials for inflammatory bowel disease (PL 14736). Inflammopharmacology. 2006 (opens in a new tab)
- 8. Xiao B, et al. Orally targeted delivery of tripeptide KPV via hyaluronic acid-functionalized nanoparticles efficiently alleviates ulcerative colitis. Mol Ther. 2017 (opens in a new tab)
- 9. NCPA. FDA grants enforcement discretion for compounding six peptides. October 29, 2026 (opens in a new tab)
- 10. FDA. Certain bulk drug substances for use in compounding that may present significant safety risks (current as of April 22, 2026) (opens in a new tab)
- 11. FDA. Bulk drug substances used in compounding under section 503A (opens in a new tab)