KLOW is GLOW with one addition. Understanding it is mostly a matter of understanding that addition — KPV — and then applying the same caution about combination evidence that applies to any blend.
The two blends are identical except for one component. GLOW contains GHK-Cu 50mg, BPC-157 10mg and TB-500 10mg, for 70mg. KLOW contains the same three at the same amounts, plus KPV 10mg, for 80mg.
That makes the comparison unusually clean: any difference between them is attributable to the KPV, at least in principle. In practice no controlled comparison of the two has been published.
KPV is a tripeptide — lysine, proline, valine — corresponding to the C-terminal fragment of α-melanocyte stimulating hormone.
α-MSH is a hormone with several roles, including pigmentation signalling through melanocortin receptors and a separate line of research interest in inflammatory signalling. KPV is the fragment associated with the latter.
Importantly, KPV is not associated with the melanocortin-driven pigmentation effects of the full α-MSH sequence or of analogues such as Melanotan II. It is a different fragment with a different profile, and the two should not be conflated.
Preclinical work has examined KPV in inflammatory signalling pathways, with a concentration of studies in gastrointestinal models — intestinal epithelium in particular.
The work is in cell culture and rodent models. There is no clinical trial establishing efficacy in humans for any indication.
Research interest in short fragments like KPV partly reflects practical considerations: a tripeptide is inexpensive to synthesise to high purity and simpler to characterise than a full hormone sequence.
As with GLOW, there is no controlled study of the KLOW combination. Four individual literatures of differing depth do not add up to evidence about a four-component blend.
If anything the caution is stronger here, because each additional component increases the number of possible interactions and makes attribution of any observed effect correspondingly harder.
This article is reference material describing published research. It is not medical advice, not a therapeutic claim, and contains no dosing or administration guidance.