What is Palmitoyl pentapeptide-4?
Palmitoyl pentapeptide-4 is a short peptide with a 16-carbon fatty chain attached, which helps it sit in the skin. It is sold under the trade name Matrixyl, and its sequence is written C16-KTTKS in the research.
It is most often marketed as a collagen-supporting peptide. Most of the data are from cell studies, and it is often sold in blends with other peptides.
How it is thought to work
In cultured human fibroblasts, the cells that make collagen, C16-KTTKS increased collagen production in a concentration-dependent way.
The 2013 study linked that effect to how the molecule self-assembles into fibres near its critical aggregation concentration. Whether the same happens in living skin at product concentrations is not shown in the records checked.
What the studies show
Every record below was checked against the paper. Where a result is from cells, animals or a combination product, the entry says so.
Jones RR, et al. Mol Pharm. 2013;10(3):1063–1069. (opens in a new tab)
Design. Lab study on human dermal and corneal fibroblasts, with the peptide in solution at several concentrations.
Finding. Collagen production rose with concentration, and the authors link this to the peptide’s self-assembly.
Paccola AGL, et al. Molecules. 2025;30(16). (opens in a new tab)
Design. In vitro study on human dermal fibroblasts. Palmitoyl pentapeptide-4 and tetrapeptide-21 were tested alone and with injectable platelet-rich fibrin, over 72 hours.
Finding. Combinations with platelet-rich fibrin increased cell viability and collagen-related gene activity more than either part alone. The authors say the effect was strongest with tetrapeptide-21.
Kachooeian M, et al. ACS Omega. 2022;7(28):24695–24704. (opens in a new tab)
Design. Animal study over 21 days comparing Matrixyl patches and creams, with controls.
Finding. Wound closure improved in the Matrixyl groups compared with the untreated control. This is wound healing in animals, not a wrinkle result.
How it is used
Listed as Palmitoyl Pentapeptide-4 in serums, eye products and anti-ageing moisturisers, alone or in blends. Amounts are rarely disclosed.
Blends can contain several peptides, so check the full ingredient list rather than the name on the front of the pack.
Safety
The animal wound study reports healing outcomes and does not discuss side effects in its abstract. No human safety trial of the peptide alone was found in the records checked.
Patch-test any new product first, especially if your skin is sensitive.
Talk to a doctor, dermatologist or pharmacist before starting a new active, especially if you are pregnant, have a skin condition, or use prescription treatments.
Questions
Is Matrixyl the same as palmitoyl pentapeptide-4?
Yes. Matrixyl is the trade name for palmitoyl pentapeptide-4, written C16-KTTKS in research. Some products sold as Matrixyl are blends, so the name on the front may not tell you everything inside.
Does it reduce wrinkles?
Lab studies show it can increase collagen production in skin cells. The records checked for this page include no controlled human wrinkle trial of the peptide alone.