Novel Cosmetic Peptide AP31 Shows Anti-Aging Benefits for Younger Skin in Clinical Study | Research

The takeaway

A cosmetic peptide called acetyl dipeptide-31 amide (AP31) demonstrated anti-inflammatory and collagen-building effects in lab studies and improved early signs of aging in a 12-week clinical trial of 46 patients.

12-week improvement
A regimen containing the cosmetic peptide AP31 significantly improved early aging signs and reduced skin glycation index in 46 patients

What the researchers found

The study yielded several key findings across multiple experiments:

- Clinical evaluation of 180 subjects identified the earliest aging signs as uneven skin tone, fine lines, and roughness, with aging turning points in the mid-twenties for lighter skin types and mid-thirties for darker skin types

- Younger skin cells produced more reactive oxygen species (ROS) after UV exposure but were also more responsive to treatment

- Acetyl dipeptide-31 amide (AP31) demonstrated anti-inflammatory effects and stimulated production of extracellular matrix components including collagen and elastin in vitro

- A 12-week clinical study of 46 patients showed that a regimen containing AP31, sunscreen, and bakuchiol significantly improved early aging signs and reduced skin glycation index

- Elasticity loss begins in the 20s and collagen content decreases progressively with age

Why it matters

Cosmetic peptides are a rapidly growing category in skincare, but many lack clinical evidence. This study provides both mechanistic data (how AP31 works at the cellular level) and clinical proof (that it improves aging signs in real patients). The concept of 'pre-aging' intervention — treating skin before significant damage occurs — represents a preventive approach that could preserve skin quality longer than waiting to treat established aging.

How the study worked

This was a multi-part study: (1) clinical evaluation of 180 subjects across all Fitzpatrick Skin Types to identify pre-aging features; (2) in vitro studies comparing young and old dermal fibroblasts' responses to UVA exposure and treatments; (3) in vitro evaluation of AP31's effects on inflammation and extracellular matrix production; (4) a 12-week clinical study of 46 patients with mild to moderate photoaging testing a regimen containing AP31, sunscreen, and bakuchiol. Skin glycation index was assessed via UV-fluorescence and cross-polarized imaging.

What this study cannot tell us

The clinical study included only 46 patients and lasted 12 weeks — a relatively short period for assessing anti-aging benefits. The regimen combined AP31 with sunscreen and bakuchiol, making it difficult to isolate AP31's specific contribution to the observed improvements. The study was published in a dermatology journal and may have industry involvement (common for cosmetic ingredient studies). Long-term safety and efficacy data are not available. In vitro effects on fibroblasts don't always predict clinical outcomes.

How to read the evidence

This combines in vitro mechanistic data with a small clinical trial. The multi-method approach is a strength, but the 46-patient clinical study is relatively small, short-term, and the multi-component regimen makes it difficult to attribute effects specifically to the peptide. This represents moderate evidence for a cosmetic ingredient.

When this study was published

Published in 2025, this is a very recent study representing the current state of cosmetic peptide development and the emerging concept of 'pre-aging' skincare intervention.

The bigger picture

Cosmetic peptides represent a significant commercial and scientific sector within the broader peptide field. While therapeutic peptides dominate clinical research, cosmetic peptides like AP31 demonstrate that short synthetic peptides can have meaningful biological effects on skin cells. This study adds to evidence that early skincare intervention with bioactive peptides may help delay visible aging, supporting the growing 'preventive dermatology' movement.

Questions still open

How much of the clinical improvement was due to AP31 specifically versus the sunscreen and bakuchiol components of the regimen?
Do the anti-aging benefits of AP31 persist beyond 12 weeks, and is there continued improvement with longer use?
How does AP31 compare to established cosmetic peptides like palmitoyl pentapeptide-4 (Matrixyl) in head-to-head testing?

Common questions

What is a cosmetic peptide and how does it work on skin?

Cosmetic peptides are short chains of amino acids designed to signal skin cells to behave in specific ways. AP31 (acetyl dipeptide-31 amide) signals skin fibroblasts to produce more collagen and elastin — the structural proteins that keep skin firm and elastic — while also reducing inflammation. These peptides are small enough to penetrate the skin surface and interact directly with the cells responsible for skin repair and maintenance.

At what age should you start using anti-aging skincare?

This study found that the earliest signs of skin aging appear in the mid-twenties for lighter skin types and mid-thirties for darker skin types, with elasticity loss beginning in the 20s. The researchers suggest that 'pre-aging' intervention — starting protective skincare before significant damage occurs — can help preserve skin quality. Sunscreen remains the single most important anti-aging measure at any age.

Read the original research

INDIVIDUAL ARTICLE: A Scientific Approach to Defining, Evaluating, and Treating Pre-Aging With a Cosmetic Regimen Containing a Novel Cosmetic Peptide, Acetyl Dipeptide-31 Amide (AP31).

Journal of drugs in dermatology : JDD, 24(5), 51181s4-51181s14

View on PubMed ↗Publisher’s paper ↗

Citation

Farris, Patricia; Frey, Cheri; Parsa, Ramine; Miller, Dara; Shyr, Thomas; Li, Wen-Hwa. (2025). INDIVIDUAL ARTICLE: A Scientific Approach to Defining, Evaluating, and Treating Pre-Aging With a Cosmetic Regimen Containing a Novel Cosmetic Peptide, Acetyl Dipeptide-31 Amide (AP31).. Journal of drugs in dermatology : JDD, 24(5), 51181s4-51181s14. https://doi.org/10.36849/JDD.51181