The Evidence

50+ years of independent
GHK-Cu research.

Every study below was funded and conducted independently — by dermatologists, biochemists, and research institutions with no connection to Koppā. We didn't run these studies. We built our formulas around what they found. Each entry links to the published source.

The Evidence

50+ years of published research.

Organised by benefit area. Every study was conducted independently — by dermatologists, biochemists, and research institutions with no connection to KOPPĀ. Each entry links directly to the published source.

The Foundation

How GHK-Cu was first isolated and what makes it biologically unique

1 study
01
Discovery

Isolation of GHK from Human Plasma

Pickart, L. & Thaler, M.M. · 1973 · University of California, San Francisco

The study that started everything. Biochemist Loren Pickart discovered that when blood plasma from young donors was added to liver cells from older donors, the older cells began functioning like younger tissue. The active compound responsible was isolated and identified as GHK — a tripeptide naturally present in human blood.

Key finding A factor in young plasma could reset older cells to produce proteins characteristic of younger, healthier tissue.
Read the original research

Collagen & Skin Firmness

Clinical evidence for structural skin rebuilding, wrinkle reduction, and dermal thickening

7 studies
02
CollagenWound Healing

GHK-Cu Stimulation of Collagen, Glycosaminoglycans, and Wound Repair

Maquart, F.X. et al. · 1988 · Laboratory of Biochemistry, Faculty of Medicine, Reims, France

In animal and cell models, GHK-Cu significantly stimulated the production of collagen, proteoglycans, and glycosaminoglycans — the structural building blocks of skin. The peptide also promoted angiogenesis and accelerated wound closure. This was the foundational evidence for GHK-Cu's role in skin repair.

Key finding In this study, GHK-Cu was associated with increased collagen synthesis and wound closure rates.
Read the published study
03
CollagenSkin Firmness

Comparative Trial: GHK-Cu vs. Vitamin C vs. Retinoic Acid for Collagen Production

Abdulghani, A.A. et al. · 1998 · International Journal of Cosmetic Science

A human trial comparing topical GHK-Cu against vitamin C and retinoic acid (prescription retinoid). After one month of daily application, GHK-Cu produced collagen increases in 70% of participants — outperforming both vitamin C (50%) and retinoic acid (40%).

Key finding In this study on GHK-Cu, a 70% collagen response rate was reported in a head-to-head comparison with vitamin C and a prescription retinoid.
Read the published study
04
Skin FirmnessCollagen

GHK-Cu Facial Cream for Photoaged Skin

Leyden, J.J. et al. · 2002 · American Academy of Dermatology

71 women with mild to advanced photoaging applied a GHK-Cu cream twice daily for 12 weeks. The treatment group showed statistically significant improvements in skin density, skin thickness, fine lines, and laxity compared to both placebo and vitamin C control groups.

Key finding In this study on GHK-Cu, 12 weeks of use was associated with measurable increases in skin density and thickness, and a 67% reduction in wrinkle volume among participants.
Read the published study
05
Skin Firmness

GHK-Cu Eye Cream for Periorbital Wrinkles

Abdulghani, A.A. et al. · 1998 · International Journal of Cosmetic Science

41 women with photodamage around the eye area used a GHK-Cu eye cream for 12 weeks. The treatment reduced periorbital wrinkles and outperformed both placebo and vitamin K cream for improving skin density and firmness around the eyes.

Key finding In this study on GHK-Cu, participants saw under-eye wrinkles reduced by 55% over 12 weeks, compared with placebo and vitamin K.
Read the published study
07
CollagenSkin Firmness

Epidermal and Dermal Thickening with GHK-Cu

Finkley, M.B. et al. · 2005

67 women applied GHK-Cu cream twice daily for 12 weeks. In this study on GHK-Cu, researchers reported measurable changes in epidermal and dermal thickness, associated with improvements in the look of firmness rather than surface hydration alone.

Key finding Measurable thickening of both skin layers after 12 weeks, consistent with genuine dermal remodeling — not temporary plumping.
Read the published study
10
Skin FirmnessCollagen

GHK-Cu Nano-Carrier Delivery for Wrinkle Reduction

Badenhorst, T. et al. · 2016 · International Journal of Cosmetic Science

GHK-Cu delivered via nano-lipid carriers was tested against a Matrixyl 3000 control serum. Over 8 weeks, the GHK-Cu formulation reduced facial wrinkle volume by 55.8% and wrinkle depth by 32.8%. The study also confirmed GHK-Cu increased collagen and elastin at concentrations as low as 0.01 nM.

Key finding In this study on GHK-Cu, the formulation was associated with a 55.8% reduction in wrinkle volume and measurable collagen/elastin increases, with GHK-Cu active at extremely low concentrations.
Read the published study
11
Collagen

Clinical Trial: GHK-Cu Topical Gel for Collagen Density

Yuvan Research Inc. · 2023 · IRB-Approved Human Clinical Trial

21 women applied a GHK-Cu topical gel daily for 3 months. On average, participants saw a 28% increase in collagen density. The top quartile experienced a 51% increase — one of the most significant collagen improvements documented for a topical peptide product.

Key finding In this study on a GHK-Cu topical gel, participants saw a 28% average increase in collagen density over 3 months, with top responders seeing 51%.
Read the published study

Wound Healing & Repair

Evidence for accelerated tissue repair, post-procedure recovery, and barrier restoration

3 studies
06
Wound Healing

GHK-Cu for Post-Laser Skin Recovery

Miller, et al. · 2006 · Archives of Facial Plastic Surgery

Patients recovering from CO2 laser resurfacing were treated with topical GHK-Cu. The treatment group healed faster and showed improved wound closure compared to standard post-procedure care — suggesting GHK-Cu can accelerate the skin's natural repair process after controlled damage.

Key finding Topical GHK-Cu reduced healing time after laser resurfacing versus standard wound care.
Read the published study
09
Wound Healing

GHK-Cu Wound Healing in Ischemic Tissue

Canapp, S.O. et al. · 2003 · Veterinary Surgery

Full-thickness wounds were treated daily with topical GHK-Cu for 13 days. Wound size decreased by 64.5% in the GHK-Cu group versus just 28.2% in untreated controls — demonstrating the peptide's ability to accelerate healing even in compromised, low blood-flow tissue.

Key finding In this study on GHK-Cu, wound size was reduced by 64.5% in tissue with restricted blood flow, versus untreated controls.
Read the published study
13
Wound Healing

GHK-Cu Systemic Healing Enhancement

Multiple research groups (compiled) · Various · Animal model studies

Across multiple animal studies, GHK-Cu demonstrated an unexpected systemic effect: when applied in one area of the body, it improved healing at distant body sites. These treatments increased collagen production, angiogenesis, and wound closure — suggesting GHK-Cu triggers a body-wide repair response, not just a local one.

Key finding GHK-Cu appears to activate body-wide repair signaling — not just localized effects at the application site.
Read the compiled research

Anti-Aging & Gene Expression

How GHK-Cu modulates gene activity, reduces inflammation, and defends against oxidative stress

2 studies
08
Gene Expression

Gene Expression Profiling of GHK-Cu

Pickart, L., Vasquez-Soltero, J.M., & Margolina, A. · 2012 · Journal of Aging Research / 2018 · Cosmetics (MDPI)

Using the Broad Institute's Connectivity Map, researchers analyzed how GHK-Cu affects human gene expression at the cellular level. In this study on the GHK-Cu molecule, the peptide was reported to influence a large share of human genes, shifting many age-related expression patterns. Of the affected genes, 59% were upregulated and 41% were downregulated — spanning pathways studied for their role in tissue and collagen biology.

Key finding GHK-Cu modulates over 4,000 human genes — one of the broadest biological effects ever documented for a single naturally occurring peptide.
Read the published study
12
Anti-InflammatoryAntioxidant

Anti-Inflammatory and Antioxidant Actions of GHK-Cu

Pickart, L. & Margolina, A. · 2018 · International Journal of Molecular Sciences (PMC)

A comprehensive review confirmed that GHK-Cu suppresses pro-inflammatory signals (including IL-6 and TNF-α), reduces oxidative damage markers, and upregulates the body's antioxidant defense enzymes. The authors also documented the age-related decline in plasma GHK-Cu levels and its correlation with reduced regenerative capacity across multiple organ systems.

Key finding GHK-Cu actively suppresses inflammation and oxidative stress — two of the primary drivers of visible skin aging.
Read the published study

13 studies. 50 years of independent research. One molecule your body already knows how to use.

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The research is published.

50 years of independent science behind one peptide your body already recognizes. See how we formulate with it.