What does KPV stand for?

The single-letter codes for its three residues: lysine (K), proline (P), valine (V).

Is KPV related to melanotan?

Both derive from alpha-MSH. Melanotan II is a cyclic analogue of the whole hormone; KPV is just its C-terminal three residues, without the pigmentation-driving portion.

Why does PubChem give the wrong compound for KPV?

The three-letter string matches an unrelated organic acid. The peptide is indexed as Lys-Pro-Val, CID 125672.

KPV

What Is KPV? A Complete Research Overview

JMWritten & reviewed by Jack Muncaster · Founder, UK PeptidesLast reviewed 2026-08-234 cited sources

KPV is a tripeptide — lysine, proline, valine — corresponding to the C-terminal three residues of alpha-melanocyte-stimulating hormone. At 342.43 Da it is among the smallest research peptides in circulation, and it retains reported anti-inflammatory activity without the melanocortin receptor effects that drive pigmentation.

Key facts

Sequence: Lys-Pro-Val
Length: 3 residues
Molecular weight: 342.43 Da
Formula: C16H30N4O4
PubChem CID: 125672 (as Lys-Pro-Val)
Parent: alpha-MSH, residues 11–13
Parent MW: 1,664.9 Da
PubMed records: ~34 on anti-inflammatory work

Where it comes from

Alpha-melanocyte-stimulating hormone is a 13-residue peptide best known for driving pigmentation through melanocortin receptors. It also has well-described anti-inflammatory activity, and that activity was localised to its C-terminal three residues — Lys-Pro-Val. KPV is those three residues synthesised alone.

Why isolating the tripeptide was the point

Alpha-MSH does two quite different things, and for research on the anti-inflammatory arm the pigmentation activity is a confound rather than a bonus. Separating the C-terminal fragment was an attempt to keep one and discard the other — the same reductionist logic behind TB-500's isolation from thymosin beta-4, applied to a hormone with two distinct effects.

Research material referenced

KPV 10mg — third-party HPLC tested

View — £24.99

How small it actually is

Three residues and 342.43 Da makes KPV the smallest compound in this library apart from GHK at 340.38. For comparison, ipamorelin is 711.9, BPC-157 is 1,419.5, and retatrutide is around 4,731. That size has real consequences: rapid clearance, minimal structure, and very little for an analytical method to work with.

What the literature reports

Roughly 34 indexed records on KPV's anti-inflammatory work. Kannengiesser and colleagues reported anti-inflammatory potential in murine colitis models in Inflammatory Bowel Disease in 2008. Xiao and colleagues examined orally targeted delivery via hyaluronic acid-functionalised carriers in Molecular Therapy in 2017 — a delivery paper, which tells you the compound's own oral bioavailability was the obstacle being addressed.

The identifier trap

Searching PubChem for KPV returns 2-oxo-5-phenylpentanoic acid, an unrelated organic compound at 192.21 Da. The peptide is indexed under Lys-Pro-Val at CID 125672. Anyone checking a certificate by searching the three-letter abbreviation will find the wrong molecule, which is worth knowing before doing it.

Regulatory position

KPV holds no marketing authorisation from the MHRA, EMA or FDA. It is supplied here for laboratory research only, and no claim is made about inflammation or any condition in any person.

Extended research context

The KPV deep dive

Deep dive: two functions in one hormone, and the case for splitting them

Alpha-MSH is a thirteen-residue peptide cleaved from proopiomelanocortin, and it does two things that have almost nothing to do with each other. Its core sequence engages melanocortin receptors on melanocytes and drives melanin synthesis - the activity it is named for. Separately, it carries anti-inflammatory activity that Brzoska and colleagues localised to its C-terminal end, a paper titled 'terminal signal' precisely because the finding was that the signal sits at the terminus rather than in the receptor-binding core. That is an unusually clean functional separation, and it produced two research compounds pulling in opposite directions from one parent. KPV takes the C-terminal three residues and discards the pigmentation activity. Melanotan II does the reverse - a cyclic analogue built around the receptor-binding portion to maximise exactly what KPV was designed to leave behind. Same hormone, opposite halves.

Deep dive: what happens when you shrink a molecule fivefold

Going from alpha-MSH at 1,664.9 Da to KPV at 342.43 Da is not a trim, it is a change of category. A 1,665 Da peptide is firmly a cell-surface ligand - far too large to cross a membrane passively, so whatever it does must begin at a receptor. A 342 Da tripeptide is small enough that intracellular access becomes plausible, which is why KPV's reported mechanism is described in terms of NF-kappaB signalling rather than melanocortin receptor engagement. The consequence is rarely stated: if the fragment acts inside the cell and the parent acts at its surface, then the anti-inflammatory activity of the two is not necessarily the same phenomenon, and read-across between them should run cautiously in both directions. Fragment logic assumes the fragment is the parent minus something. Here it may be the parent minus something plus a different route of access.

Deep dive: the delivery paper is the most informative thing in the literature

Xiao and colleagues published in Molecular Therapy in 2017 on delivering KPV orally using hyaluronic acid-functionalised nanoparticles targeted to inflamed intestinal tissue. Read as a result it is a delivery success. Read as a statement about the compound it is more interesting: nobody builds a targeted nanoparticle carrier for a molecule that already reaches its target. The existence of that work says the free tripeptide's arrival at inflamed tissue was the limiting problem - which follows directly from being 342 Da, highly soluble and rapidly cleared. It is the same signal that CJC-1295's DAC modification carries for growth hormone secretagogues, or that lipidation carries across the whole incretin class: when the engineering effort goes into getting a compound to stay and arrive rather than into making it more active, the pharmacokinetics were the bottleneck.

Research applications

▸Melanocortin fragment structure-activity research
▸NF-kappaB pathway and cytokine production studies in culture
▸Murine models of induced intestinal inflammation
▸Targeted peptide delivery and carrier system development
▸Comparative work on parent hormones and isolated fragments
▸Analytical method development for very short peptides

Handling checklist

✓Verify identity against Lys-Pro-Val, CID 125672, at 342.43 Da
✓Do not search PubChem for 'KPV' - it returns an unrelated organic acid
✓Store lyophilised, cold, dry and dark
✓Use low-binding consumables; a small cationic peptide adsorbs to surfaces
✓Reconstitute gently down the vial wall and swirl, never shake
✓Aliquot into single-use volumes to avoid freeze-thaw cycling
✓Expect no disulfide or oxidation satellites - no cysteine, no methionine

Common research-handling mistakes

Learnt from thousands of researcher orders across our UK labs.

✗ Searching PubChem for 'KPV' to verify a certificate

Fix: That returns CID 13294447, 2-oxo-5-phenylpentanoic acid at 192.21 Da, an unrelated compound. Search Lys-Pro-Val for CID 125672.

✗ Treating KPV and alpha-MSH findings as interchangeable

Fix: They differ fivefold in mass and the fragment may act intracellularly where the parent cannot. Read across cautiously in both directions.

✗ Assuming a colitis model result speaks to inflammatory bowel disease

Fix: Induced colitis in a mouse is acute and chemical; human IBD is chronic, heterogeneous and immunologically complex.

✗ Expecting to quantify KPV by absorbance at 280 nm

Fix: There is no aromatic residue in the sequence, so there is no usable absorbance there.

✗ Attributing unexplained low recovery to degradation

Fix: KPV is chemically robust - no cysteine, methionine or asparagine. Adsorption to glass and plastic is the more likely cause.

Continue researching

Peer-reviewed guides, comparators and matched reference materials.

Frequently asked questions

What does KPV stand for?: The single-letter codes for its three residues: lysine (K), proline (P), valine (V).
Is KPV related to melanotan?: Both derive from alpha-MSH. Melanotan II is a cyclic analogue of the whole hormone; KPV is just its C-terminal three residues, without the pigmentation-driving portion.
Why does PubChem give the wrong compound for KPV?: The three-letter string matches an unrelated organic acid. The peptide is indexed as Lys-Pro-Val, CID 125672.

Primary sources & clinical trials

Peer-reviewed research and registered trials from PubMed, ClinicalTrials.gov, PubChem, FDA and NIH. All links open in a new tab and point to the primary source, so every claim can be verified at origin.

Written and reviewed by

Jack Muncaster · Founder, UK Peptides

Jack founded UK Peptides in Manchester after repeatedly receiving research compounds with missing or recycled paperwork. He is responsible for supplier selection, batch release decisions and the content published in this research library. Every article here is sourced to primary literature and every product page to a signed third-party certificate.

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