Acetyl octapeptide-3 vs Copper tripeptide-1
A face-cream ingredient sold to smooth lines around the eyes and forehead. It has not been properly tested on its own; one 24-person study used a mixed product. A skin-care ingredient sold to firm skin, soften wrinkles and regrow hair. The one controlled human trial, of 13 patients, found no skin benefit.
Both sit at grade C: animal and cell studies. Neither is FDA approved.
Evidence
CAnimal and cell studies
CAnimal and cell studies
Human studies cited
Animal or cell studies cited
Why the grade
The only peer-reviewed human study found that tests a product containing SNAP-8 is a 2024 split-face study in 24 people, in which a microneedle patch carrying SNAP-8 together with other actives was compared with a plain hyaluronic acid patch for 28 days. SNAP-8 has not been tested on its own against placebo, and the claim that it beats Argireline comes from the manufacturer. That is grade C.
For the skin anti-ageing use, the controlled human evidence is a single randomized trial of 13 patients after CO2 laser resurfacing, which found no objective difference in redness or wrinkles. The rest is gene-expression work in cultured cells, animal wound and lung-injury models, and cosmetic-company studies summarized in reviews written by the peptide's discoverer.
FDA
Cosmetic ingredient
Acetyl octapeptide-3 (SNAP-8) is a cosmetic ingredient. The FDA does not approve cosmetic ingredients before sale and regulates products containing it as cosmetics provided they claim only to improve appearance; it is not an approved drug for any use.
Cosmetic ingredient
Copper tripeptide-1 is a cosmetic ingredient and sits outside FDA drug approval; no copper tripeptide-1 or GHK-Cu product is approved by the FDA as a drug for any use. Injectable GHK-Cu sold online is not approved and is sold as a research chemical.
Sold for
SNAP-8 is sold as a longer, stronger version of Argireline that relaxes expression lines around the eyes and forehead when applied topically.
Copper tripeptide-1 is marketed in serums as a collagen-building, wound-healing peptide that firms skin, softens wrinkles and regrows hair.
Studies say
The mechanism is borrowed from Argireline and the clinical support is one 24-person study of a microneedle patch that mixed SNAP-8 with other actives, which is too little to say SNAP-8 itself reduces wrinkles (grade C).
Cell and animal studies show it switches on repair genes and speeds wound closure, but the one blinded human trial found no measurable skin benefit over the control regimen, so the evidence is C.
Class
Neurotransmitter-inhibiting peptide
Carrier/copper peptide
Route
Topical
Topical