Back to Peptide Library

Matrixyl

Palmitoyl Pentapeptide-4 (pal-KTTKS)

Early-Stage ClinicalNot FDA EvaluatedPrimary Endpoint Met

Early-stage clinical evidence exists but is limited. Larger, well-controlled trials are needed.

A cosmetic skincare ingredient that signals skin cells to produce more collagen (the protein that keeps skin firm) by mimicking a natural signal that appears when collagen breaks down. A 12-week clinical trial of 93 people showed significant wrinkle reduction compared to placebo, though most supporting research has been industry-funded.

11 studiesUpdated 2026-03-09Topical

This entry is a cited research summary, not an established treatment reference. Dosing language is included as source context, not as medical instruction.

Clinical bottom lineMixed evidence

Matrixyl has moderate clinical evidence but is not FDA-approved.

Early-stage clinical evidence exists but is limited. Larger, well-controlled trials are needed.

Safety Summary

Matrixyl has a favorable safety profile with over 20 years of commercial use. The CIR assessed palmitoyl pentapeptide-4 as safe in cosmetic formulations. The EWG gives it a safety score of 1 (very safe). Robinson et al. (2005) reported good tolerability across all skin types in their 93-subject RCT. No serious adverse effects have been reported in the literature. Minor skin irritation is possible at very high concentrations, but Matrixyl is effective at extremely low concentrations (as low as 3 ppm), minimizing risk. Suitable for sensitive skin. However, systematic human safety reporting is limited -- the FDA FAERS database contains no adverse event reports for Matrixyl, which reflects absence of drug-level monitoring rather than proof of long-term safety PMID 39858482.

Clinical check-in

If real-world use or exposure is being considered, review potential interactions, contraindications, and monitoring needs with a licensed clinician rather than relying on summary copy alone.

See cited studies on this page (11)

Cited sources

Every claim on this page links to one of the 11 sources below. Identifiers are PubMed (PMID), ClinicalTrials.gov (NCT), or DOI; click through to the source of record before acting on a claim.

  1. 1doi:10.1111/j.1467-2494.2005.00261.xDOI
  2. 2Promoting production in the extracellular matrix without promoting inflammationReference
  3. 3Double-blind, Randomized Trial on the Effectiveness of Acetylhexapeptide-3 Cream and Palmitoyl Pentapeptide-4 Cream for Crow's FeetReference
  4. 4PMID 23320752PubMed
  5. 5PMID 40871567PubMed
  6. 6PMID 27877059PubMed
  7. 7PMID 33195061PubMed
  8. 8PMID 39858482PubMed
  9. 9PMID 31407889PubMed
  10. 10PMID 21462614PubMed
  11. 11Cosmetic Peptide Efficacy: Clinical Trial EvidenceReference