01   The Science

Five decades
of peer-reviewed evidence.

GHK-Cu is not a new ingredient. It is one of the most extensively studied peptides in regenerative medicine — first isolated from human plasma in 1973 and continuously validated ever since. Here is what the science actually says.

50+Years of research
4,000+Genes influenced
+70%Collagen synthesis*
pH 6.5Peak bioavailability
02   GHK-Cu

The molecule
that rebuilds skin.

GHK (Glycyl-L-Histidyl-L-Lysine) is a naturally occurring tripeptide first isolated from human plasma by Pickart and Thaler in 1973. It has a high affinity for copper ions, forming the GHK-Cu complex that acts as a potent biological signal for tissue repair and regeneration.

GHK-Cu plasma levels decline dramatically with age — from approximately 200 ng/ml at age 20 to around 80 ng/ml by age 60. This decline correlates directly with the skin's decreasing capacity to repair itself and the visible onset of structural aging.

The peptide's amino acid sequence is present in the alpha 2(I) chain of type I collagen. When collagen is damaged, proteolytic enzymes release GHK into the site of injury — triggering the skin's own repair cascade. Topical application at 2% replicates this biological signal.

Collagen synthesis
In a study comparing GHK-Cu to vitamin C and retinoic acid, GHK-Cu resulted in collagen increases in 70% of volunteers — outperforming both comparators. (Abdulghani et al., 1999)
Fibroblast activation
GHK-Cu combined with LED irradiation increased collagen synthesis by 70% and basic fibroblast growth factor production by 230% compared to LED alone. (Pickart et al., PMC6073405)
Gene expression
Large-scale gene expression analyses show GHK-Cu influences over 4,000 human genes involved in tissue repair, inflammation control, and regenerative signalling — effectively resetting gene expression toward a healthier state.
12-week clinical study
A facial cream containing GHK-Cu applied for 12 weeks to 71 women with mild to advanced photoaging increased skin density and thickness, reduced fine lines, and improved overall appearance. (Leyden et al.)
Skin firmness
Clinical studies measured improvements in skin firmness of 20–30% after 12 weeks of topical GHK-Cu treatment, with concurrent increases in elastin synthesis. (Pulse & Remedy, 2025)
03   Ectoin

The hydration shield
from extremophile bacteria.

Ectoin is a naturally occurring stress-protection molecule produced by extremophilic bacteria to survive in extreme conditions — intense heat, desiccation, high salinity, and UV exposure. It has been studied for over 30 years for its ability to protect biological structures from environmental damage.

Its mechanism is unique: rather than sitting on the skin's surface as an occlusive barrier, Ectoin binds water molecules at a cellular level — forming a stable hydration complex that protects cell membranes, stabilises proteins, and reduces transepidermal water loss (TEWL) from within.

In the RHIVA formula, Ectoin serves a dual purpose — protecting the skin barrier during the GHK-Cu regeneration process, and reducing the potential for irritation that can accompany active ingredient delivery.

TEWL reduction
Ectoin-containing emulsions produced a statistically significant reduction in TEWL of up to 15% and a reduction of redness by 30% in controlled clinical studies. (PMC12158106)
Barrier function
In a study of 104 participants, 2% Ectoin cream versus placebo showed significant improvements in dry and sensitive skin over four weeks — with hydration levels remaining higher than baseline even after stopping application. (Chemist Confessions, 2025)
Anti-inflammatory
A systematic review of clinical trials confirmed Ectoin's efficacy in reducing inflammation markers and improving skin hydration in atopic dermatitis and other barrier-compromised conditions. (PMC8850511)
UV protection
In vitro studies demonstrate that Ectoin protects cell cultures from UV and H2O2-induced damage by regulating antioxidant enzymes and upregulating genes in the PI3K/AKT signalling pathway.
04   Delivery

Penetration
is everything.

A peptide that stays on the skin's surface has no clinical effect. GHK-Cu must penetrate through the stratum corneum to reach the dermis where fibroblasts reside. Research confirms that GHK-Cu and its copper complexes are able to migrate through the membrane model of the stratum corneum — but only in the correct formulation environment.

The RHIVA microemulsion is an ultra-light, nanoscale oil-in-water carrier system designed to maximise transdermal delivery. It contains no silicones or occlusive agents that would form a surface barrier and reduce penetration. pH is calibrated to 6.5 — the range at which GHK-Cu has peak bioavailability and optimal copper binding.

2%GHK-Cu — efficacious threshold confirmed in clinical literature
pH 6.5Optimal copper binding and stratum corneum permeability
0Silicones, alcohols, or occlusive agents
12wkMinimum consistent use for measurable clinical results
References
Pickart L, Thaler M. (1973). Tripeptide in human serum which prolongs survival of normal liver cells. Nat New Biol.
Abdulghani et al. (1999). Collagen production comparison of GHK-Cu vs vitamin C and retinoic acid in human volunteers.
Pickart L et al. (2018). Regenerative and Protective Actions of the GHK-Cu Peptide. PMC6073405, Int J Mol Sci.
Badenhorst T et al. (2016). Effects of GHK-Cu on MMP and TIMP Expression, Collagen and Elastin. Walsh Medical Media.
Leyden J et al. 12-week facial cream study, 71 participants, photoaged skin. Collagen density and thickness outcomes.
PMC8850511. Topical Ectoine Application in Inflammatory Skin Diseases: Systematic Review. PMC, 2022.
PMC12158106. The Influence of Ectoine on Skin Parameters Damaged by CO2 Laser. Molecules, 2025.
PMC4508379. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int, 2015.