Reviewed & approved by Dr. Nova Reyes · Last checked 2026-10-15. ← Back to Evidence Library
The "KLOW" blend: what the evidence says
At a glance
What it is: a gray-market vial mixing four peptides: GHK-Cu, KPV, BPC-157 and TB-500. [UNVERIFIED: blend composition comes from product listings, not a primary source] R1
What the evidence says: the blend itself has never been studied, in animals or people. Each part has its own thin evidence, covered separately below. R2
Biggest risks: four unknowns in one vial. Four ingredients mean four chances for the wrong compound, wrong amount or contamination, and no one has studied how they act together. R10
| Rating | |
|---|---|
| Human Human evidence (the blend) | No human data (nothing at all: the blend has never been studied in people or animals) |
| Animal Animal evidence (the blend) | No studies (the blend has never been studied in animals) |
| Regulatory | Not FDA-approved · contains WADA-banned components (BPC-157, TB-500) R7, R8 |
| Established human dose | Unknown Unknown |
Evidence verdict: Blend in people: No human data (nothing at all) · Blend in animals: No studies · Each ingredient is rated on its own page Card verdict: No human data (4-peptide blend of BPC-157, TB-500, GHK-Cu & KPV never studied together in humans or animals)
This page reports what studies used. It is not dosing advice.
Legend: HUMAN data · ANIMAL / LAB data · UNKNOWN · UNVERIFIED: not yet confirmed against a primary source
Taking these together? See Combining peptides.
What is it?
"KLOW" is a marketing name for a four-peptide mix. No published study has tested this combination. Below, each ingredient is handled on its own. R1, R2
Each component, separately
- GHK-Cu: small, mixed human skin data. Injected GHK-Cu is essentially untested in people. See GHK-Cu.
- BPC-157: promising in animals (mostly one lab). Essentially untested in people. See BPC-157.
- TB-500: the 7-amino-acid fragment of thymosin beta-4. Essentially untested in people; most quoted research is on the full protein. See TB-500.
- KPV: a 3-amino-acid piece (Lys-Pro-Val) of the hormone alpha-MSH. Animal In mice, KPV reduced colitis (gut inflammation) when given in drinking water and in other colitis models. Human Essentially untested in people. We found no human trial, and FDA reports no human exposure data. R3, R7
Is it safe?
- Unknown No safety data for the blend, in animals or people.
- Unknown No human safety data for injected KPV, GHK-Cu or TB-500. Very little for BPC-157 (see each page).
- Caution Theoretical concern: three of the four (BPC-157, TB-500/Tβ4, GHK-Cu) are reported to promote new blood vessel growth, which helps healing but could in theory also feed a tumor. Whether combining them adds to this is unknown. See each page.
What we don't know
- Unknown Anything about the blend itself: dose, effect, safety, interactions
- Unknown Human data for KPV
- Unknown Long-term safety
Is it legal?
Not FDA-approved. Two components are banned at all times by WADA, the World Anti-Doping Agency (2026 list): BPC-157 (S0) and TB-500 (S2.3). KPV and GHK-Cu are not named on the list. Whether S0 applies to them is not confirmed. FDA has flagged all four components among compounding substances (pharmacies preparing custom medicines for individual patients, with a prescription) with safety risks (GHK-Cu for injectable routes). For KPV, FDA says it found no human exposure data. As of Oct 15, 2026. R7, R8
What's in the vial?
A blend is harder to test than a single peptide. Each of the four ingredients needs its own identity and amount check. We test retail vials blind under the Open Peptide Standard. See results at /tests/. A passing test covers one batch, tested on one date. It does not mean the compound itself is safe. R10
What do users report?
Self-report, not evidence.
Unknown TBD. We'll only list this once we can cite a public source.
Study details
R3 Animal KPV animal and lab studies
These are doses researchers used, not recommendations.
| Species | Model | Route | Doses | Outcome | Citation |
|---|---|---|---|---|---|
| Mouse (+ human cells) | DSS and TNBS colitis | Oral, in drinking water | Caution not in abstract; nanomolar in cells | Less colitis; uptake via PepT1 transporter | PMID 18061177 |
| Mouse | DSS and transfer colitis | Caution not in abstract | Caution not in abstract | Faster recovery, less inflammation; rescued MC1R-deficient mice | PMID 18092346 |
R1, R2, R8, R10 Background and regulatory (as of Oct 15, 2026)
- R1 UNVERIFIED Blend composition from vendor listings only (not named or linked per policy). KPV = alpha-MSH(11–13), Lys-Pro-Val (Kannengiesser 2008, PMID 18092346; Dalmasso 2008, PMID 18061177).
- R2 No PubMed record for the combination (search Oct 15, 2026).
- R7 FDA: BPC-157, TB-500, injectable GHK-Cu and KPV are each on FDA's list of substances previously in Category 2 whose nominations were withdrawn. For KPV: "FDA has not identified any human exposure data on drug products containing KPV administered via any route" (FDA page).
- R8 WADA 2026: S0 names BPC-157; S2.3 names "Thymosin-ß4 and its derivatives e.g. TB-500". KPV, GHK-Cu not named. WADA 2026 list
- R10 Open Peptide Standard: each component tested for identity and content separately. Unknown Results pending.
Full reference list (all verified on PubMed, Oct 15, 2026)
- Dalmasso G, et al. Gastroenterology. 2008;134(1):166-78. doi:10.1053/j.gastro.2007.10.026. PMID 18061177
- Kannengiesser K, et al. Inflamm Bowel Dis. 2008;14(3):324-31. doi:10.1002/ibd.20334. PMID 18092346
Component pages carry their own verified references.
Disclaimer
This page is for education and harm reduction. It is not medical advice and not a recommendation to use the KLOW blend or any of its components. Its safety in humans is not established. Please talk to a clinician you trust, especially if you have or have had cancer, are pregnant or breastfeeding, or are a tested athlete. Seek care right away for a serious reaction, and report it to FDA MedWatch (https://www.fda.gov/safety/medwatch).