The process by which epithelial cells at wound edges proliferate and migrate across the wound bed to restore an intact tissue surface. Re-epithelialization is the primary measure of wound closure and one of the most clinically relevant healing endpoints—a wound is functionally “healed” when its surface is covered.

In the peptide literature, re-epithelialization rates are reported in studies of BPC-157, GHK-Cu (topical application), and Thymosin Beta-4 (RGN-259 eye drops for corneal epithelial healing). Cenegermin (recombinant NGF), the FDA-approved peptide eye drop, specifically targets corneal re-epithelialization in neurotrophic keratitis—making it one of the few peptide compounds where re-epithelialization has been demonstrated in controlled human trials rather than animal models alone.