Palmitoyl Pentapeptide-4 (Matrixyl)

What it is

A synthetic lipopeptide consisting of the pentapeptide sequence KTTKS conjugated to a palmitoyl (C16 fatty acid) chain. Developed by Sederma SAS and Procter & Gamble, it launched in 2000 under the trade name Matrixyl. KTTKS is the minimum effective fragment of procollagen type I C-terminal propeptide (residues 212-216), retaining approximately 80% of the parent molecule's extracellular matrix-stimulating activity. It functions as a matrikine signal peptide that mimics collagen degradation products, stimulating fibroblasts to upregulate collagen I, collagen III, and fibronectin synthesis through TGF-beta signaling. The palmitoyl group enhances skin penetration by increasing lipophilicity. A landmark double-blind clinical study demonstrated statistically significant wrinkle reduction at concentrations as low as 3 ppm, with tolerability superior to retinol.

Community-reported ranges

Clinical data sourced from published peer-reviewed studies. Concentration ranges from cosmetic industry formulation standards. Matrixyl is a cosmetic ingredient, not a drug. Not dosing guidance.

Frequently discussed alongside

Based on community forum discussions. Not a recommendation to combine compounds.

Published research

The landmark Robinson et al. (2005) double-blind, placebo-controlled, split-face study enrolled 93 women aged 35-55 and demonstrated that moisturizer containing 3 ppm Pal-KTTKS produced statistically significant wrinkle and fine line reduction vs. placebo over 12 weeks, measured by optical profilometry and expert grading. Comparative studies found 3 ppm Pal-KTTKS performed similarly to 700 ppm (0.07%) retinol for wrinkle improvement with superior tolerability. Tsai et al. (2007) demonstrated that KTTKS promotes type I collagen expression through upregulation of TGF-beta signaling in tendon cells. Sederma's proprietary studies using 3D face acquisition over 28-56 days confirmed improvements in wrinkle depth, volume, and collagen content. The CIR Expert Panel completed a comprehensive safety assessment in September 2023, confirming safety for cosmetic use at current concentrations.

Reported side effects

From community self-reports. Not from controlled studies.

Palmitoyl Pentapeptide-4 is exceptionally well tolerated. Clinical studies, CIR safety assessments, human repeated insult patch tests (HRIPT), Ames mutagenicity tests, micronucleus genotoxicity tests, and endocrine disruptor assays (YES/YAS) all returned negative results. Robinson et al. (2005) confirmed that the peptide was well tolerated by the skin at clinical concentrations. Comparative studies found significantly better skin tolerability than retinol. No significant adverse effects have been reported in clinical studies or post-market surveillance across over two decades of commercial use. Suitable for all skin types including sensitive skin.

Regulatory status