Copper Peptide Microneedling Hair Regrowth Study (2025) Research Summary Hairgenetix GHK Peptide Hair Growth Clinical Trial (2016) Research Summary Hairgenetix Copper peptides (GHK Cu) have been studied for decades for their role in tissue repair and that same biology applies to hair. Research shows GHK Cu may help strengthen existing hair follicles, reduce GHK Cu Peptides Serum TryDeloura GHK Cu Peptides: Unlocking the Copper Peptide Revolution in Skin Care