Skin & aging Signal peptide
Hexapeptide-9
Regulatory status
Status at a glance
503A compounding status
Not nominated
We found no pending nomination for the 503A bulks list. Unless the substance has another legal pathway (for example, a USP monograph or use in an FDA-approved drug), 503A pharmacies generally may not compound with it.
- FDA approval
- Not FDA-approved for any use
- 503B outsourcing
- Not determined
- Anti-doping (WADA)
- Not on the WADA Prohibited List
- DEA schedule
- Not a controlled substance
About peptide status
Most peptides discussed here are not FDA-approved for any use, and products labeled “research use only” are not for human use. Removal from Category 2 does not authorize compounding. PCAC votes are non-binding recommendations; FDA and HHS make the final decisions.
This is not medical or legal advice, and we do not publish dosing, sourcing or reconstitution information. Talk with a licensed clinician before using any peptide.
If you think you are having a medical emergency, call 911.
Key takeaway
Hexapeptide-9 is a synthetic six-amino acid "signal" peptide whose sequence mirrors a short motif found in human collagen. Laboratory work suggests it signals skin cells to build more supporting matrix, which is the basis for its use in products aimed at the appearance of firmness and fewer fine lines. As of 2026, independent human evidence for the standard ingredient is limited, with the one controlled human study testing a chemically modified version rather than hexapeptide-9 itself.
At a glance
- What it is
- Cosmetic ingredient, a collagen-inspired signal peptide
- FDA status
- As a cosmetic ingredient rather than a drug, does not require FDA approval
- Research
- Activity supported mainly by laboratory and manufacturer data
- Main uses
- Products targeting the look of firmness, smoother texture, and fine lines
- Evidence strength
- Low research
Summary
Hexapeptide-9 is a cosmetic signal peptide based on collagen. Learn how it is thought to work in skin and how limited the human evidence still is.
What is hexapeptide-9?
Hexapeptide-9 is a peptide of six amino acids whose sequence mirrors a short motif found in human collagen, the protein that gives skin its structure. In skincare it is used as a "signal" or messenger peptide, meant to prompt skin cells rather than to add collagen directly. It is sold under trade names such as Collaxyl and is a cosmetic ingredient, not a drug.
How does it work?
Laboratory studies describe hexapeptide-9 as a matrikine, a peptide fragment that acts as a signal to skin cells. The proposed mechanism is that it tells dermal fibroblasts and surface keratinocytes to increase production of extracellular matrix components such as collagen, as well as to strengthen the junction between the upper and lower layers of skin. The idea is that healthier-looking matrix supports the appearance of firmer, smoother skin.
These are laboratory and manufacturer findings about how the peptide behaves in cell models. In finished cosmetics the benefit is described in appearance terms, such as the look of firmness and reduced fine lines, rather than as a claim to rebuild collagen.
Is it FDA-approved?
Safety note
Status: As a cosmetic ingredient rather than a drug, does not require FDA approval
Category: Cosmetic and topical · Primary body area: Skin & aging
No, and it does not need to be. The FDA does not pre-approve cosmetic ingredients. A cosmetic may describe how it affects the look and feel of skin, while a claim to change the body's structure would make a product a drug. Hexapeptide-9 is used within the cosmetic boundary, for the appearance of the skin.
What is it used for?
Hexapeptide-9 is used in "anti-aging" and firming serums and creams. The appearance goals are the look of firmer skin, improved texture and tone, and a reduction in the appearance of fine lines. It is often paired with other peptides and hydrating ingredients.
What does the research show?
Editor’s note
Evidence strength: Low research
The ingredient's rationale rests on laboratory and manufacturer data, and the only controlled human study tested a modified version rather than standard hexapeptide-9, so there is no sound human evidence for the ingredient itself.
The direct human evidence is limited:
- According to PubMed, a randomized, controlled trial reported wrinkle improvements, but it tested a cyclized derivative of the molecule rather than standard hexapeptide-9, and it was industry-sponsored.
- Other studies use the peptide inside delivery systems or combination products, so the ingredient's individual effect is hard to isolate.
- There is no independent, well-controlled human trial of standard hexapeptide-9 on its own, and supplier efficacy claims are largely unpublished.
What are the side effects?
Hexapeptide-9 is generally considered well tolerated on the skin, with low irritation potential at cosmetic use levels. As with any new skincare ingredient, a patch test is sensible for sensitive or reactive skin, since individual responses vary.
Sources: a randomized controlled trial of a cyclized hexapeptide-9 derivative (Chang et al., Journal of Cosmetic Dermatology, 2025, DOI: 10.1111/jocd.70290), indexed on PubMed; and cosmetic ingredient reference data on hexapeptide-9. This document is educational and does not constitute medical advice.
Registered human trials
0 registered human trials on ClinicalTrials.gov that we reviewed
Sources
- [1]
- [2]
- [3]
- [4]
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