Matrixyl

Sederma's trade name for palmitoyl pentapeptide-4 (pal-KTTKS), a fatty-acid-conjugated fragment of type I procollagen used in topical cosmetic formulations and studied for collagen-signaling and wrinkle-reduction effects in skin.

Also referenced as: Palmitoyl Pentapeptide-4, Palmitoyl Pentapeptide-3, Pal-KTTKS, Palmitoyl-KTTKS

Also appears in: Longevity

What is Matrixyl?

Matrixyl is the trade name (owned by Sederma) for palmitoyl pentapeptide-4, a synthetic peptide built from the five-amino-acid sequence KTTKS — a fragment of the C-terminal propeptide of type I procollagen — conjugated to palmitic acid to improve lipophilicity and formulation stability. It is one of the most widely used peptides in commercial anti-aging skin care, and it appears in the research-peptide market both as a raw material and in pre-formulated topical serums sold alongside other cosmetic peptides such as Argireline and SNAP-8.

How it works

• The parent sequence KTTKS is a “matrikine” — a signal fragment derived from an extracellular-matrix protein. In fibroblast culture, KTTKS was identified as the minimum procollagen-derived sequence needed for potent stimulation of collagen and fibronectin production; the parent C-terminal propeptide fragment it comes from increases type I collagen, type III collagen, and fibronectin in a dose- and time-dependent manner (Katayama et al., J Biol Chem, 1993;268(14):9941-9944).
• The working hypothesis is a feedback loop: fibroblasts interpret free propeptide fragments as evidence of collagen turnover and respond by upregulating new matrix synthesis; the palmitoyl tail was added to make the hydrophilic pentapeptide more skin-compatible and stable (reviewed in Abu Samah & Heard, Int J Cosmet Sci, 2011;33(6):483-490).
• The palmitoylated molecule is surface-active and self-assembles into nanotape structures in solution; collagen stimulation in human fibroblasts tracks with concentration near its critical aggregation concentration, suggesting the assembly state matters to activity (Jones et al., Mol Pharm, 2013;10(3):1063-1069).

Research status

There are no studies registered on ClinicalTrials.gov for Matrixyl or palmitoyl pentapeptide-4 — the human evidence comes from cosmetic-industry studies published in cosmetic-science journals, not from drug-development trials.

The key human study is Robinson et al., Int J Cosmet Sci, 2005;27(3):155-160: a 12-week, double-blind, placebo-controlled, split-face study in 93 women (ages 35-55) comparing a moisturizer containing 3 ppm pal-KTTKS against the same moisturizer without it. The peptide side showed statistically significant improvement in wrinkles and fine lines by both instrument-based and expert-grader assessment, with good skin tolerance. The authors were Procter & Gamble scientists, and independent replication of this result is limited.

The skin-penetration picture is only partly resolved. Choi et al., Biomol Ther (Seoul), 2014;22(4):321-327 found that both peptides are rapidly degraded by skin proteases, with pal-KTTKS more stable in skin homogenate than unmodified KTTKS. In permeation testing through full-thickness hairless mouse skin in vitro, neither compound made it all the way through to the receptor fluid — but intact pal-KTTKS was recovered from every skin layer, including a small amount in the dermis (0.3 µg/cm²), while unmodified KTTKS was undetectable in any layer. That supports the rationale for palmitoylation, though how much intact peptide actually reaches dermal fibroblasts from a finished product dosed at parts-per-million levels remains an open question. The Abu Samah & Heard review (2011) reaches a similar verdict: a sound in-vitro basis for matrix stimulation, with delivery through the stratum corneum as the main open problem.

Common dosage forms

Matrixyl is a topical-only compound in practice. Research vendors and cosmetic suppliers list it as raw lyophilized powder, as pre-diluted topical solutions or serums, and blended into multi-peptide cosmetic formulations (often combined with peptides such as Argireline or copper peptides). Finished cosmetic products typically contain the active at low parts-per-million concentrations. It is not sold as an injectable vial format the way metabolic or recovery peptides are.

Key considerations

• Regulatory status: Palmitoyl pentapeptide-4 is a cosmetic ingredient, not an approved drug — it has never been through FDA drug review. The Cosmetic Ingredient Review’s Expert Panel for Cosmetic Ingredient Safety concluded in a 2024 final report that palmitoyl pentapeptide-4 is safe in cosmetics in the present practices of use and concentration.
• Naming confusion is common: Matrixyl (palmitoyl pentapeptide-4, pal-KTTKS) is a different molecule from Matrixyl 3000 (a blend of palmitoyl tripeptide-1 and palmitoyl tetrapeptide-7) and Matrixyl Synthe’6 (palmitoyl tripeptide-38). It is also distinct from unmodified KTTKS itself (INCI: pentapeptide-4), the unpalmitoylated parent sequence. Older ingredient labels used the pre-2006 INCI name “palmitoyl pentapeptide-3” for the same compound. Product listings that say “Matrixyl” may contain any of these.
• Evidence gap: The strongest human data is a single industry-run split-face study; there are no registered clinical trials, and while in-vitro permeation work shows intact pal-KTTKS penetrating into skin layers, its rapid degradation by skin proteases and the tiny fraction reaching the dermis mean the link between fibroblast-culture mechanism and topical benefit remains incompletely demonstrated.
• Safety signals: Published studies report good tolerability at cosmetic use levels, with low rates of irritation or sensitization; there is essentially no data on non-topical routes of administration.
• Trade-name provenance: “Matrixyl” is a Sederma (Croda) trademark for a specific ingredient preparation; research-market listings using the name are generic pal-KTTKS of varying provenance, not the branded ingredient.