{"id":"matrixyl","name":"Matrixyl","aliases":["palmitoyl pentapeptide-4","pal-KTTKS","palmitoyl pentapeptide-3","Matrixyl 3000"],"url":"https://lyoresearch.com/compounds/matrixyl","class":{"id":"cosmetic-peptides","name":"Cosmetic peptides","url":"https://lyoresearch.com/classes/cosmetic-peptides"},"summary":"Matrixyl is palmitoyl pentapeptide-4 (pal-KTTKS), a five-amino-acid fragment of type I collagen with a palmitic acid tail added so it can cross the skin barrier. Its human evidence is a 93-woman, 12-week, split-face randomised trial run by Procter & Gamble, which found significant reduction in wrinkles and fine lines against the vehicle control by both instrumental and expert-grader analysis. It is a legal cosmetic ingredient everywhere LYO covers and is not a medicine.","overall_grade":"C","overall_grade_meaning":"weak human evidence","human_trials":"1 split-face RCT (n=93, 12 weeks)","regulatory_status":"Cosmetic ingredient","molecule":{"formula":"C39H75N7O10","molecular_weight":"802.1","cas":"214047-00-4","pubchem_cid":9897237,"sequence":"Pal-KTTKS","sequence_note":null,"note":null},"pharmacokinetics":{"basis":"none","route":"Topical (cosmetic serum or cream)","half_life":"No human pharmacokinetic study; the palmitoyl tail is added to aid skin penetration, which has not been quantified in people","licensed_regimen":null,"product":null,"source":null},"outcomes":[{"outcome":"Wrinkles and fine lines (topical)","grade":"C","grade_meaning":"weak human evidence","effect_size":"small","adverse":false,"human_studies":"1 split-face RCT (n=93, 12 wk)","evidence":"A 12-week double-blind split-face study in 93 women aged 35–55 applied 3 ppm pal-KTTKS in a moisturiser to one side of the face and vehicle to the other. Both quantitative image analysis and expert graders found significant improvement in wrinkles and fine lines on the treated side. Split-face design controls for the person; it does not control for the sponsor, which developed and sells the ingredient.","references":[{"citation":"Robinson LR, Fitzgerald NC, Doughty DG, Dawes NC, Berge CA, Bissett DL. Topical palmitoyl pentapeptide provides improvement in photoaged human facial skin.","where":"Int J Cosmet Sci, 2005;27:155–160","url":"https://pubmed.ncbi.nlm.nih.gov/18492182/"}],"verbatim":{"text":"Pal-KTTKS was well tolerated by the skin and provided significant improvement vs. placebo control for reduction in wrinkles/fine lines by both quantitative technical and expert grader image analysis.","citation":"Robinson LR, Fitzgerald NC, Doughty DG, Dawes NC, Berge CA, Bissett DL. Topical palmitoyl pentapeptide provides improvement in photoaged human facial skin.","url":"https://pubmed.ncbi.nlm.nih.gov/18492182/"}},{"outcome":"Collagen synthesis","grade":"D","grade_meaning":"no human evidence","effect_size":"not measurable","adverse":false,"human_studies":"None in vivo","evidence":"The mechanism rests on fibroblast culture work showing that KTTKS stimulates collagen I, collagen III and fibronectin production. No human study has measured collagen synthesis in skin after topical pal-KTTKS.","references":[]},{"outcome":"Safety (topical)","grade":"C","grade_meaning":"weak human evidence","effect_size":"not measurable","adverse":true,"human_studies":"1 RCT (n=93, 12 wk)","evidence":"The trial reported the peptide was well tolerated by the skin over twelve weeks. Decades of cosmetic use at parts-per-million concentrations have produced no safety signal.","references":[{"citation":"Robinson LR, Fitzgerald NC, Doughty DG, Dawes NC, Berge CA, Bissett DL. Topical palmitoyl pentapeptide provides improvement in photoaged human facial skin.","where":"Int J Cosmet Sci, 2005;27:155–160","url":"https://pubmed.ncbi.nlm.nih.gov/18492182/"}]}],"regions":[{"region":"European Union","status":"Cosmetic ingredient","note":"Lawful in cosmetics. No authorised health claim."},{"region":"United States","status":"Cosmetic ingredient","note":"Sold in cosmetics without pre-market approval; not an approved drug."},{"region":"United Kingdom","status":"Cosmetic ingredient","note":"Lawful in cosmetics under the UK Cosmetics Regulation."},{"region":"Australia","status":"Cosmetic ingredient","note":"Topical cosmetic use is not regulated as a medicine."},{"region":"Canada","status":"Cosmetic ingredient","note":"Permitted in cosmetics; subject to cosmetic notification."},{"region":"Sport (WADA)","status":"Not named","note":"Not on the Prohibited List."}],"faq":[{"q":"Is Matrixyl better evidenced than argireline?","a":"Methodologically yes: twelve weeks against four, 93 people against 60, split-face control, and two independent measurement methods. Both rest on a single industry-run trial, so both are graded C."},{"q":"Is Matrixyl 3000 the same thing?","a":"No. Matrixyl 3000 is a different blend containing palmitoyl tripeptide-1 and palmitoyl tetrapeptide-7. The trial described here tested pal-KTTKS on its own."},{"q":"Does Matrixyl build collagen in skin?","a":"That is the mechanism proposed from fibroblast culture. No human study has measured collagen in skin after applying it — the trial measured how the skin looked, not what it contained."}],"references":[{"cite":"Robinson LR, Fitzgerald NC, Doughty DG, Dawes NC, Berge CA, Bissett DL. Topical palmitoyl pentapeptide provides improvement in photoaged human facial skin.","where":"Int J Cosmet Sci, 2005;27:155–160","url":"https://pubmed.ncbi.nlm.nih.gov/18492182/","note":"93 women aged 35–55; 12-week double-blind split-face study of 3 ppm pal-KTTKS versus vehicle. Procter & Gamble authors."},{"cite":"PubChem compound record: palmitoyl pentapeptide-4.","where":"PubChem, read 29 Oct 2026","url":"https://pubchem.ncbi.nlm.nih.gov/compound/9897237","note":"Formula, molecular weight, CAS and the Pal-KTTKS sequence used on this page."}],"last_reviewed":"2026-10-29","literature_searched_to":"2026-10-29","changelog":[{"date":"2026-10-29","note":"Initial publication. Grade C on one industry-run split-face trial."}],"license":"CC BY 4.0 — cite as “LYO Research” with a link.","methodology":"https://lyoresearch.com/methodology"}