Monograph in Tissue-repair & anti-inflammatory peptides
GHK-Cu
A naturally occurring tripeptide that binds copper, long used in skin-care products. The biology is rich; the controlled human evidence is one small randomized study with no objective benefit.
Also called Copper tripeptide-1 · Prezatide copper · Glycyl-L-histidyl-L-lysine copper
Best evidence: Limited / early human data
One small randomized human study (13 completers, topical) found no objective difference; most claims come from laboratory and animal work and from reviews.
Not FDA-approved · injectable-route nomination withdrawn
Residue Editorial Team · updated
What is GHK-Cu?
GHK-Cu is the tripeptide glycyl-L-histidyl-L-lysine bound to a copper(II) ion. GHK occurs in human plasma and declines with age; laboratory work links GHK-Cu to collagen synthesis and wound repair1PubMedGHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Pickart L et al. Biomed Res Int. 2015.. The only randomized human study found, after laser resurfacing, showed no objective difference versus a regimen without it2PubMedEffects of topical copper tripeptide complex on CO2 laser-resurfaced skin. Miller TR et al. Arch Facial Plast Surg. 2006.. FDA lists GHK-Cu for injectable routes among withdrawn compounding nominations3FDACertain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. U.S. FDA, content current as of 04/22/2026..
Key findings
- GHK is present in human plasma, saliva and urine but declines with age; it is proposed to act as a complex with copper(II)1.
- Reviews describe stimulation of collagen, elastin and glycosaminoglycan synthesis and of fibroblast and keratinocyte proliferation in experimental systems4PubMedThe human tri-peptide GHK and tissue remodeling. Pickart L J Biomater Sci Polym Ed. 2008.,5PubMedRegenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Pickart L & Margolina A Int J Mol Sci. 2018..
- In a randomized study after CO₂ laser resurfacing (13 completers), blinded evaluation found no difference in erythema resolution or wrinkles; only a patient questionnaire favored GHK-Cu (p=0.04)2.
- GHK was discovered in 1973 as an activity in human albumin6PubMedThe human tripeptide GHK-Cu in prevention of oxidative stress and degenerative conditions of aging: implications for cognitive health. Pickart L et al. Oxid Med Cell Longev. 2012..
- FDA cites immunogenicity risk for injectable GHK-Cu and says there are limited human data to inform safety3.
What is GHK-Cu, chemically?
| PubChem CID | 71587328 “Prezatide copper” |
|---|---|
| Formula | C14H23CuN6O4+ |
| Molecular weight | 402.92 g/mol |
| CAS (as listed) | 89030-95-5 |
| FDA UNII | 6BJQ43T1I9 |
| InChIKey | NZWIFMYRRCMYMN-ACMTZBLWSA-M |
| Route in trials | Topical in human studies |
| Mechanism | Copper(II)-binding tripeptide (Gly-His-Lys); modulates tissue-remodeling pathways |
What is GHK-Cu?
GHK is the tripeptide Gly-His-Lys. It binds copper(II) with an affinity similar to the copper-transport site on albumin, forming the complex GHK-Cu4. It was discovered in 1973 as an activity in human albumin that caused old human liver tissue to synthesize proteins like younger tissue6. GHK is present in human plasma, saliva and urine and its level declines with age1. PubChem's record for the copper complex (prezatide copper) is used for the identifiers above7PubChemPubChem compound record: Prezatide copper. C14H23CuN6O4+ · MW 402.92 g/mol..
How is GHK-Cu thought to work?
Reviews describe GHK-Cu as a modulator of tissue remodeling. In experimental systems it attracts repair cells such as macrophages and capillary cells, has anti-inflammatory and antioxidant actions, increases synthesis of collagen, elastin, metalloproteinases and growth factors, and increases proliferation of fibroblasts and keratinocytes4. More recent work used gene-expression data to propose that GHK regulates many biochemical pathways at once5.
These reviews are enthusiastic in tone — one describes GHK's actions as all appearing "health positive"5. They summarize mechanism well but are not evidence of clinical effect.
Is there evidence in humans?
The randomized study. Patients undergoing CO₂ laser resurfacing around the mouth were randomized to post-treatment skin regimens with or without GHK-Cu. Thirteen completed the study. Computer analysis and blinded evaluators found no significant differences in erythema resolution, and all patients improved in wrinkles and skin quality with no between-group difference. A validated patient questionnaire showed a significant difference favoring GHK-Cu for overall skin quality (p=0.04)2.
Cosmetic claims. Reviews state that in cosmetic products GHK-Cu has been found to tighten skin, improve elasticity and reduce fine lines1; the underlying cosmetic studies are mostly not indexed as clinical trials in PubMed8PubMedPubMed search: (GHK-Cu[tiab] OR "copper tripeptide"[tiab] OR "glycyl-histidyl-lysine"[tiab] OR "prezatide"[tiab]). 134 records at fetch..
Registered studies. ClinicalTrials.gov lists a recruiting phase 2 trial of topical GHK-Cu gel for acute skin wounds9TrialTopical GHK-Cu Gel for Acute Skin Wound Healing. Hudson Biotech · PHASE2 · recruiting. and a completed facial-skin study10TrialTrial Assessing the Impact on Facial Skin Quality, Hydration, and Skin Barrier of Three (3) Hydrafacial Treatments in Adults of All Skin Types.. Austin Institute for Clinical Research · PHASE4 · completed..
Is GHK-Cu FDA-approved?
| Record | Status | Source |
|---|---|---|
| FDA approval | No approved application Drugs@FDA returned no application for “GHK-Cu”. | openFDA |
| Compounding: nominated, then withdrawn GHK-Cu (for injectable routes of administration) | Withdrawn nomination FDA still lists its safety concerns: “Compounded injectable drugs containing GHK-Cu may pose risk for immunogenicity due to the potential for aggregation and peptide-related impurities. There are limited data in humans to inform safety-related considerations.” | 3 |
FDA's withdrawn-nominations list includes "GHK-Cu (for injectable routes of administration)". It notes that compounded injectable GHK-Cu may pose risk for immunogenicity due to aggregation and peptide-related impurities, and that there are limited data in humans to inform safety3. The listing is route-specific; it does not address topical cosmetic use.
What is still unknown?
- Adequately powered randomized trials with objective skin or wound endpoints.
- Any controlled human data for injection, the route FDA flags3.
What effects has GHK-Cu shown, by body system?
Each row is graded separately using the Residue evidence scale: a compound can carry an A for one use and a D for another.
| System | What was observed | Grade |
|---|---|---|
| Skin (topical) | No objective difference after laser resurfacing in a 13-patient RCT; subjective skin-quality rating favored GHK-Cu2. | C |
| Wound healing | Accelerated wound healing in rats, mice, pigs and dogs, per review1. | D |
| Gene expression | Reported to up- and down-regulate at least 4,000 human genes in expression datasets1,5. | D |
| Injectable use | Limited human safety data; FDA cites immunogenicity risk3. | D |
How much research is there on GHK-Cu?
| Phase | Studies | Breakdown |
|---|---|---|
| Phase 2 | 1 | 0 completed, 1 active or recruiting, 0 stopped, 0 other |
| Phase 4 | 1 | 1 completed, 0 active or recruiting, 0 stopped, 0 other |
| Not applicable | 1 | 0 completed, 1 active or recruiting, 0 stopped, 0 other |
Compare and continue
Questions readers ask
What is GHK-Cu?
A complex of the tripeptide glycyl-L-histidyl-L-lysine (GHK) with a copper(II) ion. GHK has a copper affinity similar to the copper-transport site on albumin4.
Does GHK-Cu work for skin?
Laboratory and animal data are extensive1. In the one randomized human study we found, 13 patients after laser resurfacing showed no objective differences in redness or wrinkles; a questionnaire favored GHK-Cu2.
Is injectable GHK-Cu FDA-approved?
No. FDA lists 'GHK-Cu (for injectable routes of administration)' among withdrawn compounding nominations, citing immunogenicity risk and limited human safety data3.
Are there clinical trials of GHK-Cu?
ClinicalTrials.gov lists a small number, including a recruiting phase 2 trial of topical gel for acute skin wounds9.
References
Every source below was retrieved from its official API or page and cached on the data-edition date. Numbers match the margin notes.
- 1 PubMed Pickart L, Vasquez-Soltero JM, Margolina A. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int 2015. PMID 26236730; doi:10.1155/2015/648108.
- 2 PubMed Miller TR, Wagner JD, Baack BR, et al. Effects of topical copper tripeptide complex on CO2 laser-resurfaced skin. Arch Facial Plast Surg 2006. PMID 16847171; doi:10.1001/archfaci.8.4.252.
- 3 FDA Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. U.S. FDA, content current as of 04/22/2026.
- 4 PubMed Pickart L. The human tri-peptide GHK and tissue remodeling. J Biomater Sci Polym Ed 2008. PMID 18644225; doi:10.1163/156856208784909435.
- 5 PubMed Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci 2018. PMID 29986520; doi:10.3390/ijms19071987.
- 6 PubMed Pickart L, Vasquez-Soltero JM, Margolina A. The human tripeptide GHK-Cu in prevention of oxidative stress and degenerative conditions of aging: implications for cognitive health. Oxid Med Cell Longev 2012. PMID 22666519; doi:10.1155/2012/324832.
- 7 PubChem PubChem compound record: Prezatide copper. C14H23CuN6O4+ · MW 402.92 g/mol.
- 8 PubMed PubMed search: (GHK-Cu[tiab] OR "copper tripeptide"[tiab] OR "glycyl-histidyl-lysine"[tiab] OR "prezatide"[tiab]). 134 records at fetch. PMID ghk-cu.
- 9 ClinicalTrials.gov Topical GHK-Cu Gel for Acute Skin Wound Healing. Hudson Biotech · PHASE2 · recruiting.
- 10 ClinicalTrials.gov Trial Assessing the Impact on Facial Skin Quality, Hydration, and Skin Barrier of Three (3) Hydrafacial Treatments in Adults of All Skin Types.. Austin Institute for Clinical Research · PHASE4 · completed.