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KLOW

Also known as KLOW blend, GLOW + KPV, KPV / GHK-Cu / BPC-157 / TB-500 blend

GLOW with KPV added: a four-peptide vendor mixture with no published research on it as a mixture.

preclinical Blends & stacks research chemical

At a glance

Category
Blends & stacks
Status
research chemical
Route
subcutaneous
Half-life
Not established, and no single figure is meaningful. None of the four components has published human pharmacokinetics 5; KPV in particular has no validated pharmacokinetics in any species 23.
Onset
unknown
Molecular weight
Not applicable to a mixture. Individually: approximately 342 g/mol for KPV, approximately 340 g/mol for GHK (approximately 404 g/mol as the copper complex), 1419.5 g/mol for BPC-157 and approximately 889 g/mol for the TB-500 fragment.
Sequence
Not applicable: a co-lyophilised mixture of four peptides. KPV (Lys-Pro-Val), GHK (Gly-His-Lys) as a copper(II) complex, BPC-157 (GEPPPGKPADDAGLV) and Ac-LKKTETQ.

Not a medicine and not approved anywhere. 'KLOW' is a seller's name — literally GLOW with a K for KPV in front of it — and carries no pharmacological or regulatory meaning. In the US it cannot lawfully be compounded: BPC-157 was placed in category 2 of the FDA's interim 503A bulks list in September 2023 ('may present significant safety risks'), and 'Thymosin Beta-4, Fragment (LKKTETQ)' is listed by name in the same category. Sold as grey-market material labelled 'for research use only'.

Doping status: Prohibited: BPC-157 falls under S0 and TB-500 under S2, which makes the blend prohibited for athletes regardless of the status of the other two components.

Checked against the WADA 2026 Prohibited List. For a specific product and country, Global DRO is the lookup athletes are expected to use — the List names substances, not brand names.

What is in it

Mechanism of action

KLOW has no mechanism of its own. It is the GLOW mixture with a fourth peptide added, and the marketing logic is that KPV contributes an anti-inflammatory element to a repair-oriented stack. Nothing in the literature supports that the four act together, and adding a fourth barely-studied compound to three barely-studied compounds does not strengthen a rationale — it adds a fourth unknown and a further set of untested interactions.

KPV is the C-terminal tripeptide of alpha-MSH. In cell culture and in mouse colitis models it inhibits NF-kB signalling and reduces pro-inflammatory cytokine production, and it is taken up by intestinal epithelium via the PepT1 transporter 2. That last point matters here: the mechanism worked out in animals depends on delivery into the intestinal lumen, whereas KLOW is injected subcutaneously, which bypasses that route entirely and has never been studied.

The other three components are described in the entries for GHK-Cu, BPC-157 and TB-500. In short: injected GHK-Cu has no published human study, BPC-157 has no published randomised human trial, and the TB-500 heptapeptide has no published human study and no human pharmacokinetics.

There is a mechanistic tension in the mixture worth naming, because vendors do not. Two components are promoted as pro-angiogenic and pro-inflammatory-repair signals, while a third is promoted as anti-inflammatory. Whether combining them produces a useful balance, mutual interference or no effect at all is unknown — nobody has looked. As with GLOW, the copper(II) content raises an unresolved chemical question about the stability of the other three peptides in the same solution.

What the research shows

There is no research on KLOW. PubMed returns nothing for the blend as a blend, and no registered trial of the mixture could be found. The evidence base is not the sum of four component literatures; it is empty, and the four components between them contribute not one randomised human trial.

Research in humans

No published human study of the mixture, of any design. Component by component: KPV has no published human clinical study at all and a targeted search of clinicaltrials.gov returned no registered KPV trial; BPC-157 has no published randomised controlled human trial; the TB-500 heptapeptide has no published human clinical trial and no human pharmacokinetics; injected GHK-Cu has no published human study, the GHK-Cu human data being exclusively small topical cosmetic studies.

Animal and lab research

No animal study of the four-peptide mixture exists. KPV's animal evidence is real but narrow and route-specific: DSS-induced and transfer colitis in mice, with faster recovery and lower myeloperoxidase activity, mostly using oral or nanoparticle delivery 3. Rodent colitis translates poorly to human disease, and none of it addresses subcutaneous administration alongside three other peptides.

Caveats. The composition is not standardised. The most commonly advertised format is an 80 mg vial at 50/10/10/10 mg, but formats such as 10 mg KPV with 5 mg each of BPC-157, TB-500 and GHK-Cu are also sold under the same name, so two vials labelled KLOW can differ substantially in both total mass and ratio. Beyond that: unregulated manufacture with no guarantee of identity, purity, sterility or endotoxin content; the recurring problem that 'TB-500' sometimes denotes the full thymosin beta-4 protein rather than the fragment; and the fixed ratio, which makes the product uninterpretable in use.

What it is used for

  • Marketed for gut complaints and 'gut repair', on the strength of KPV's mouse colitis data 23 — animal work in which the peptide was delivered to the intestinal lumen, not injected 2
  • Marketed for inflammatory skin conditions and skin quality
  • Marketed for soft-tissue recovery and wound healing
  • Marketed as a broader version of GLOW, which is a claim about the number of ingredients rather than about any measured effect
  • None of these uses has been studied for the mixture 5. What evidence exists belongs to the components individually — KPV in murine colitis 23 and BPC-157 in preclinical orthopaedic work 4 — and none of it was generated with the other components present

Dosing

Dose
User protocols describe volume rather than milligrams: typically 0.05-0.15 ml of reconstituted blend per injection. What that volume contains depends entirely on how much water went into the vial. Reconstituted as in the example below (an 80 mg vial in 4 ml), 0.05-0.15 ml corresponds to roughly 0.6-1.9 mg GHK-Cu with 0.13-0.38 mg each of KPV, BPC-157 and TB-500; a 2 ml reconstitution doubles all four figures
Frequency
once daily, in most circulating protocols five days per week
Route
subcutaneous
Duration
cycles of 4-8 weeks are described
  • No established dose exists. Every figure here comes from vendor pages and user protocols, and none of them derives from a study of this mixture or of any component in humans 45.
  • The dose must be given as a volume, because one injection delivers four compounds simultaneously in whatever ratio the seller chose.
  • The fixed-ratio problem is worse with four components than with three. Nothing can be titrated individually; a reaction cannot be traced to one of four candidates; and discontinuing means discontinuing all four at once. There is no experiment you can run on yourself that isolates a cause.
  • If the reason for taking this is KPV, note that the animal evidence concerns delivery to the intestinal lumen and uptake by the epithelial transporter PepT1 2, which subcutaneous injection does not achieve.
  • The GHK-Cu fraction is by far the largest by mass, so most of what is injected is a copper complex. Daily injection over weeks is an unmonitored copper load.
  • Buying the components separately costs the same information advantage that the blend removes.

These figures describe what the literature and published protocols report. They are not advice and not a dosing instruction.

Protocols

Daily injection course

user protocol — not validated

Source: Vendor pages and user protocols, stated as a volume of reconstituted blend

This is not a validated schedule. It is a pattern that circulates among users and sellers, reproduced because it is what people actually follow — not because it has been tested. No trial established these doses, this interval or this duration, and nobody is checking what is in the vial. Treat every number below as an assertion, not a finding.

Weeks 1-4 to 80.05-0.15 ml of reconstituted blend per injection, once daily, five days per week, subcutaneously
After the coursea break before repeating

Volume is the only way to state this dose, because one injection delivers four compounds in a ratio fixed by the seller. If the KPV fraction is the reason for using it, the route defeats it: the animal evidence for KPV concerns delivery to the intestinal lumen via PepT1, which subcutaneous injection does not achieve. And as with GLOW, most of the injected mass is a copper complex.

Schedules are reproduced as their source states them. Units, IU and milligrams explains why the figures are not interchangeable between products.

Reconstitution

Vial sizes
50/10/10/10 mg
Solvent
bacteriostatic water (0.9% benzyl alcohol)
Storage
Reconstituted at 2-8 °C, protected from light. The usual three to four weeks is a convention borrowed from single peptides and is not a stability finding for a four-component copper-containing solution. Powder frozen and dark.

Worked example

An 80 mg vial (50 mg GHK-Cu + 10 mg each of BPC-157, TB-500 and KPV) with 4 ml bacteriostatic water gives 12.5 mg/ml GHK-Cu and 2.5 mg/ml of each of the other three. 0.1 ml, that is 10 units on a U100 insulin syringe, contains approximately 1.25 mg GHK-Cu and 0.25 mg each of BPC-157, TB-500 and KPV. All four figures move together.

The solution is blue from the copper complex. Do not shake; let the water run down the wall of the vial. No published stability data exist for this combination in solution.

Safety

Side effects

  • Injection site reactions: pain, redness, swelling, sometimes transient discoloration from the copper complex
  • Reported anecdotally for BPC-157: anxiety, itching, fatigue, nausea, headache, dizziness
  • Reported anecdotally for TB-500: fatigue, light-headedness, flu-like feeling
  • Copper-related effects from the GHK-Cu fraction, including nausea and metallic taste; sustained excess copper is a genuine toxicological endpoint
  • For KPV there is no human safety dataset of any kind — the published work is in mice 23 — so nothing can be listed for it beyond that fact
  • Immunogenicity, named by the FDA as a risk for BPC-157 and for the LKKTETQ fragment when it placed them in category 2 of the interim 503A bulks list 1
  • The absence of a longer list reflects the absence of research rather than a clean record 45, and with four components any reaction is unattributable

Do not use if

  • Active or previous malignancy: two components are pro-angiogenic or pro-migratory (BPC-157 and the thymosin beta-4 fragment) 45, and raised thymosin beta-4 expression has been associated with invasiveness and metastasis in several tumour types
  • Wilson's disease or impaired copper handling, and concurrent copper supplementation
  • Pregnancy and breastfeeding: no data for any component
  • Children and adolescents: no data
  • Competitive athletes under the WADA code
  • Anyone using this to investigate a specific complaint: a four-way fixed mixture cannot answer which component, if any, did anything

Interactions

Not systematically studied, and no interaction between the four components has ever been examined 5. Reasoning from mechanism, one can imagine additive angiogenic effects between BPC-157 and TB-500 4, opposing inflammatory signals between KPV and the repair-oriented components 3, competition at the peptide transporter PepT1, which carries KPV and also several drug classes 2, and copper interfering with zinc status on prolonged use. None of this has been measured. Formal interaction studies with medication do not exist for any component.

Sources