Interest in azelaic acid-containing skincare has increased in recent years, particularly for formulations addressing blemish-prone skin, visible redness, uneven tone and texture. While ingredient selection provides the foundation of a formulation, it is ultimately the efficacy and tolerability of the finished product that matter to consumers.
This was the focus of the study by Gaudicheau, Ahlström, Gillbro and Åkerström, published in the International Journal of Cosmetic Science in 2026.
The eight-week randomised, prospective, split-face, vehicle-controlled study evaluated a minimalist anhydrous concentrate containing 10% azelaic acid and 0.1% retinal. Twenty-three participants completed the study, with efficacy assessed using Antera 3D imaging, standardized photography and consumer self-assessment.
A minimalist six-ingredient concentrate
The evaluated formulation contained only six ingredients: squalane, azelaic acid, caprylic/capric triglyceride, hydrogenated vegetable oil, Hordeum vulgare seed flour and retinal.
After eight weeks, the finished active formulation demonstrated statistically significant improvements compared with the vehicle:
• 18.1% improvement in overall redness
• 12.7% improvement in surface irregularities
• 22.3% improvement in pore parameters
• 5.6% improvement in skin texture
• 5.2% reduction in maximum redness intensity
Consumer self-assessment supported the instrumental findings. 95% of participants reported calmer-feeling skin, while 87% reported an improvement in overall skin condition and 82% reported reduced oiliness. Improvements in pimple size or severity and number of pimples were reported by 78% and 74% of participants respectively.
The study therefore provides a clinically evaluated example of how 10% azelaic acid can be incorporated alongside 0.1% retinal in a minimalist finished formulation for blemish-prone skin.
Azepur99® supplied by Azeco Cosmeceuticals was the azelaic acid used in the formulation evaluated by Skinome Research. Azepur99® is a cosmetic-grade azelaic acid with ≥99% purity, natural origin and micronised particle size.
Azeco Cosmeceuticals did not participate in the study design, execution, data analysis or publication; its involvement was limited to Azepur99® being used as the azelaic acid ingredient in the studied formulation.
The reported study outcomes relate to the complete formulation containing 10% azelaic acid and 0.1% retinal and should not be attributed to Azepur99® alone.
Reference
Gaudicheau C, Ahlström M, Gillbro JM, Åkerström U. Efficacy and safety of a novel anhydrous 0.1% retinal and 10% azelaic acid concentrate for blemish-prone skin: An eight-week randomized prospective split-face, vehicle-controlled study. International Journal of Cosmetic Science. 2026;00:1–13. https://doi.org/10.1111/ics.70131
