KLOW Peptide Stack: GHK-Cu, BPC-157, TB-500 and KPV Explained, With a Dosage and Frequency Chart

KLOW is a four-peptide blend: GHK-Cu, BPC-157, TB-500 and KPV in a single lyophilised vial. It is the GLOW blend (GHK-Cu, BPC-157, TB-500) with KPV added, and the "K" in the name is the only difference. The blend is sold by all three of the Bureau-scored vendors that carry combination vials, and in September 2026 the common format is an 80 mg vial holding 50 mg GHK-Cu, 10 mg BPC-157, 10 mg TB-500 and 10 mg KPV, a fixed 5:1:1:1 ratio.

This page explains what each component is and how much evidence sits behind it, what ratios the vendors actually sell, how researchers typically dose the blend (with a frequency chart), and how to reconstitute the common vial sizes so that a dose comes out in syringe units. It does not tell you what to inject. These are research compounds, and the arithmetic is the part the Bureau can help with.

The four components and their evidence level

GHK-Cu (copper tripeptide, 50 mg of the 80). A naturally occurring tripeptide bound to copper, first isolated from human plasma. It has the most human data of the four, but almost all of it is topical: cosmetic and wound-dressing studies on skin thickness, collagen and healing. Injectable GHK-Cu data in humans is thin. It makes up 62.5% of the blend by mass, and it is the component that dictates the blue colour of the reconstituted solution and the injection-site stinging researchers most often report. The FDA moved injectable GHK-Cu out of Category 2 in April 2026 and has scheduled it for advisory committee review by February 2027. The GHK-Cu guide covers the compound in depth.

BPC-157 (10 mg). A 15-amino-acid fragment of a gastric protein. The evidence base is large in rodents (tendon, ligament, gut and vascular models) and essentially absent in published human trials. On 23 July 2026 the FDA's Pharmacy Compounding Advisory Committee voted 8 to 6 to recommend it for the 503A bulks list, against the advice of FDA reviewers, who cited limited effectiveness evidence; the PCAC vote page has the detail. The BPC-157 guide covers the animal data.

TB-500 (10 mg). Sold as a synthetic fragment of thymosin beta-4, the actin-binding protein that has been through human phase 2 trials in wound and cardiac settings. The research-market product is not the trial molecule, and published data on the fragment itself is limited to animal and in vitro work. PCAC also voted 8 to 6 for TB-500 on 23 July 2026. See the TB-500 guide and, for how it differs from BPC-157, TB-500 vs BPC-157.

KPV (10 mg). The C-terminal tripeptide of alpha-melanocyte-stimulating hormone (lysine-proline-valine). The published work is mostly in mouse colitis and inflammation models, with some cell-culture data on skin and mucosa; FDA staff told PCAC that none of the studies they found were in humans, and the committee voted 8 to 6 for it anyway. It is the reason a researcher chooses KLOW over GLOW: the working hypothesis is that KPV adds an anti-inflammatory and gut-barrier element to a blend otherwise aimed at tissue repair and skin. The KPV guide covers what is and is not known.

Put bluntly: one component with human topical data, three with animal data, and no published study of the four together. Any effect claimed for the blend is an inference from single-compound work. That is the evidence level, and nothing a vendor writes on a product page changes it.

What the vendors actually sell (September 2026)

The Bureau checked the storefronts of its scored vendors in the first week of September 2026. Prices and compositions are as displayed; only the vendor's own words count.

Three things to take from the table. First, "KLOW" is not a fixed specification: Apollo's vial is 75 mg, Ascension's is 80 mg, and Pantheon's "Klow" omits TB-500 entirely. Read the composition line before you compare prices. Second, only Ascension itemises the milligrams of each component on the listing the Bureau saw; for Apollo and Amino Club, check the COA or ask before assuming 5:1:1:1. Third, the price spread is wide, from $99.99 to $199.99 for a single vial, and the cheapest listing is a "from" price whose size is not stated. The GLOW stack page runs the same comparison for the three-peptide version.

Reconstitution and units for the common vial sizes

The blend is reconstituted like any other lyophilised vial: bacteriostatic water in, swirl, do not shake. Because GHK-Cu is 62.5% of the mass and dissolves to a blue solution, the colour is expected; a clear solution from a KLOW vial is worth a query to the vendor. The reconstitution guide and bacteriostatic water guide cover the handling.

For the 80 mg vial the KLOW dosage chart gives three standard dilutions: 2 mL of bacteriostatic water for 40 mg/mL, 3 mL for 26.67 mg/mL, and 4 mL for 20 mg/mL. The 2 mL dilution is the one most protocols are written against, and on a standard 100-unit (1 mL) insulin syringe it works out as follows.

Two arithmetic points that trip people up. The dose in "mg" for a blend means milligrams of the whole mixture, not of any one peptide; a 4 mg draw from the 80 mg vial contains 2.5 mg of GHK-Cu and only 0.5 mg each of the other three. And a 2.5-unit draw is at the limit of what an insulin syringe can measure accurately, which is why the 3 mL and 4 mL dilutions exist: they make small doses into larger, more readable volumes. The KLOW dosage calculator does all of this for any vial size and water volume and shows the per-peptide content of each draw.

How researchers typically dose the blend: the frequency chart

There is no published dosing study for KLOW, so what follows is the protocol most commonly reported in research forums and reproduced by the calculator site, presented as a description of practice rather than a recommendation. It has two phases and is written against the 80 mg vial reconstituted with 2 mL.

The loading phase consumes an entire 80 mg vial in four weeks (4 mg times 5 days times 4 weeks is exactly 80 mg), so a 12-week cycle needs a second vial for maintenance, with about 32 mg left over at the end. Reported cycles run 8 to 12 weeks on and 4 to 8 weeks off. Some researchers split the daily loading dose into two 2 mg draws to reduce the volume of GHK-Cu at any one site; the weekly totals do not change. In component terms, the loading phase delivers 12.5 mg of GHK-Cu and 2.5 mg each of BPC-157, TB-500 and KPV per week; the maintenance phase delivers 3.75 mg and 0.75 mg respectively.

Compare that with the single-compound protocols on the Bureau's BPC-157 dosage page, where reported daily amounts of BPC-157 alone are commonly higher than the 0.5 mg a 4 mg KLOW draw contains. This is the trade-off in every fixed-ratio blend: convenience and one injection instead of four, against no control over the ratio. A researcher whose interest is primarily tendon or gut work may find the BPC-157 and TB-500 content of KLOW low, and the Wolverine stack (BPC-157 and TB-500 only, without the copper peptide) is the usual alternative for that case.

Storage, stability and what a vial should look like

Lyophilised KLOW stores like any lyophilised peptide: refrigerated, dark, dry, and it is generally reported to be stable for months in that state. Once reconstituted the clock starts; researchers usually plan to use a reconstituted vial within about four weeks, refrigerated. With the loading protocol above that is not a constraint, since the vial is finished in four weeks anyway. It matters more in the maintenance phase, where a second vial reconstituted with 2 mL lasts over thirteen weeks at 6 mg a week; reconstituting with less water does not help, so some researchers reconstitute the second vial and accept that part of it will be discarded, or buy a smaller GLOW-type vial for the maintenance phase. The storage guide has the general rules.

Two things worth checking on the COA. GHK-Cu is often reported at a lower purity by HPLC than the other three because of the copper complex and its chromatography, so a blend COA showing a single purity figure for the mixture is not very informative; a vendor that reports each component separately, or provides the single-compound COAs for the lots used, is giving you something you can read. And the copper content itself is not measured by a standard HPLC purity test at all. The testing guide explains what a blend COA can and cannot tell you.

Side effects reported with the components

Because there is no study of the blend, the reported side effects are those of the components. For GHK-Cu injected subcutaneously, the common reports are stinging or burning at the site, redness, and occasionally a blue tinge under the skin from the copper complex; these are volume- and concentration-dependent, which is another argument for the 3 mL or 4 mL dilution. For BPC-157 and TB-500 the animal literature reports little acute toxicity and the human reports are anecdotal: transient nausea, light-headedness, headache. For KPV there is simply not enough human data to characterise a profile. The BPC-157 side effects page and general side effects guide set out what is documented.

The unknowns that matter more than the minor ones: none of the four has published long-term human safety data by injection, the FDA's own reviewers told the July 2026 committee they had identity and safety concerns about BPC-157, TB-500 and KPV, and the FDA placed injectable GHK-Cu in Category 2 in 2023 on immunogenicity and impurity grounds before removing it for review in 2026. Anyone running a KLOW protocol is doing so ahead of the evidence, and should say so to themselves plainly.

Where to buy KLOW

Disclosure. Links in this section may earn the Bureau a commission. The scorecard weighs documentation, consistency, shipping and price; the method is on the vendor scorecard page. Composition and price are as the vendor displayed them in the first week of September 2026.

• Apollo Peptide Sciences, KLOW 75mg, $199.99: the Bureau's top-scored vendor lists a 75 mg KLOW vial. The product page the Bureau fetched did not itemise the four components; check the COA for the ratio before running a 5:1:1:1 calculation. Free shipping over $200 stated sitewide, and a newsletter pop-up offering 10% off and free shipping. Apollo review. Check price at Apollo Peptide Sciences
• Ascension Peptides, KLOW 80mg: the only listing the Bureau saw that itemises 50/10/10/10 mg on the product name, at $120 on the shop page (regular $199.99), with a batch-specific third-party COA statement. Its GLOW 70mg (50/10/10) was $110. Ascension review.
• Amino Club, KLOW from $99.99: the lowest "from" price, size not stated in the catalogue file the Bureau fetched; free shipping over $100. Amino Club review.
• Pantheon Peptides, Klow Cycle: six separate vials (BPC-157, KPV, GHK-Cu, no TB-500) for a six-week protocol, priced in CAD on the storefront the Bureau fetched. Suits a researcher who wants to control the ratio rather than accept 5:1:1:1. Pantheon review.

Whichever vial you buy, run it through the calculator with the vendor's stated milligrams rather than assuming the ratio, and keep the insulin syringe guide open the first time you draw 2.5 units. Nothing here is medical advice; these are research compounds and the Bureau does not advise anyone on using them.

Frequently Asked Questions

What is in the KLOW peptide blend?

Four peptides in one lyophilised vial: GHK-Cu, BPC-157, TB-500 and KPV. The common September 2026 format is an 80 mg vial with 50 mg GHK-Cu and 10 mg each of the other three, a 5:1:1:1 ratio; Ascension Peptides itemises exactly that on its listing. Apollo sells a 75 mg vial whose product page does not itemise the components, Amino Club lists KLOW from $99.99 without a stated size, and Pantheon's Klow Cycle is separate vials without TB-500. KLOW is the GLOW blend plus KPV; the K is the only difference.

How do researchers dose KLOW?

There is no published dosing study. The protocol most often reported, and reproduced by the calculator site, uses the 80 mg vial reconstituted with 2 mL of bacteriostatic water (40 mg/mL): a loading phase of 4 mg of blend, which is 10 units, five days a week for four weeks, then a maintenance phase of 2 mg, or 5 units, three days a week for weeks five to twelve. Reported cycles run 8 to 12 weeks on and 4 to 8 off. The loading phase uses one whole vial. This describes practice, not a recommendation.

How much bacteriostatic water for a KLOW vial?

For the 80 mg vial the standard options are 2 mL (40 mg/mL, so 4 mg of blend is 10 units), 3 mL (26.67 mg/mL, 4 mg is 15 units) or 4 mL (20 mg/mL, 4 mg is 20 units). More water makes small doses easier to measure and reduces the concentration of GHK-Cu at the injection site, which is the component most often blamed for stinging. For a 75 mg vial, 2 mL gives 37.5 mg/mL and 3 mL gives 25 mg/mL. The KLOW dosage calculator handles any vial size and water volume.

What is the difference between KLOW and GLOW?

KPV. GLOW is GHK-Cu, BPC-157 and TB-500, typically 50/10/10 mg in a 70 mg vial; KLOW adds 10 mg of KPV for an 80 mg vial. KPV is the C-terminal tripeptide of alpha-MSH, studied mainly in mouse colitis and inflammation models with no human trials FDA staff could find. Researchers choose KLOW when they want an anti-inflammatory or gut-barrier element alongside the repair and skin components. In September 2026 Ascension priced GLOW 70mg at $110 and KLOW 80mg at $120 on its shop page, so the KPV adds about $10 there.

How much evidence is there for the KLOW stack?

For the blend, none: no published study has tested the four together. For the components, GHK-Cu has human data that is almost entirely topical; BPC-157 has a large rodent literature and no published human trials; TB-500 is a fragment of thymosin beta-4, which has human phase 2 data, but the fragment itself has only animal and cell work; KPV has mouse and cell data. In July 2026 the FDA's advisory committee voted 8 to 6 to recommend BPC-157, TB-500 and KPV for compounding against the advice of FDA reviewers, who cited limited evidence. Any claimed effect of the blend is an inference.

Which vendor sells KLOW?

Of the Bureau's scored vendors, in the first week of September 2026: Apollo Peptide Sciences (KLOW 75mg, $199.99), Ascension Peptides (KLOW 80mg, itemised 50/10/10/10 mg, $120 on the shop page against a regular $199.99), and Amino Club (KLOW from $99.99, size not stated). Pantheon sells a Klow Cycle of separate vials without TB-500, priced in CAD. Compositions differ between vendors, so compare the milligrams of each component, not just the headline price. Links to these vendors on this page are affiliate links.

Research use only. The compounds discussed are sold as research chemicals and are not approved for human use. Nothing here is medical advice.