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Ingredient or product comparison

GHK-Cu Long Term Studies: Comparison Table

Human Dermatology RCT (2015) 12 months 67 adults, aged 45–65 3% topical cream, daily 37% increase in dermal density at month 12 Mild erythema in 4% (transient) Longest human trial shows sustained benefit without plateau Rat Aging Model (2012) 24 months 40 aged

This source-based comparison does not add ratings or recommend a winner.

  • Human Dermatology RCT (2015)
  • 12 months
  • 67 adults, aged 45–65
  • 3% topical cream, daily
  • 37% increase in dermal density at month 12
  • Mild erythema in 4% (transient)
  • Longest human trial shows sustained benefit without plateau
  • Rat Aging Model (2012)
  • 24 months
  • 40 aged rats
  • 10mg/kg subQ, 3×/week
  • 19% reduction in fibrosis markers; maintained fur density
  • None. CBC and liver enzymes normal throughout
  • No immune sensitization or chronic toxicity at 2 years
  • Diabetic Mouse Wound Model (2020)
  • 32 weeks (re-wound at week 20)
  • 30 diabetic mice
  • Topical hydrogel, daily
  • 38% faster wound closure on re-injury (no tolerance)
  • None reported
  • Demonstrates lack of receptor desensitization
  • In Vitro Fibroblast Study (2019)
  • 180 days continuous culture
  • Human dermal fibroblasts
  • 10 nM in culture media
  • Sustained collagen I synthesis; no apoptosis increase
  • N/A (in vitro)
  • Gene expression changes persist without cytotoxicity
  • The comparison underscores a critical finding: GHK-Cu long term studies consistently show stable or improving outcomes across extended timelines, with safety profiles that hold under multi-month scrutiny. No published study has documented tolerance, immune rejection, or chronic toxicity in mammals.