Adapinoid Shows Greater Efficacy and Tolerability Compared to Retinol

Image Credit: © Anna - stock.adobe.com

A new study compared the superior effects and tolerability of adapinoid 0.5% compared to retinol 0.5% cream when treating visible signs of aging such as facial wrinkles, fine lines, and pigmentation.¹ Adapinoid, commonly known as oleyl adapalenate, (OA) is a novel third-generation, over-the-counter retinoid that is a precursor to adapalene and has not been clinically studied for its photoaging benefits on the skin.

In this 12-week, double-blind, randomized clinical trial, 48 participants were enrolled from May 2023 to August 2023. Participants were enrolled from the Greater Sacramento region at Integrative Skin Science and Research. The study included men and women between the ages of 35 and 65 years old.

Participants were randomized to receive either topical OA 0.5% or retinol 0.5% and apply 1 to 2 pumps once a day each evening. Results were measured at baseline with follow-up visits at weeks 4, 8, and 12.

The primary outcome was changes in the appearance of wrinkle severity at 12 weeks. Secondary outcome measures included changes in erythema and skin pigmentation. Additionally, skin hydration and transepidermal water loss (TEWL) were measured using the VapoMeter, and facial photographs were taken. Self-perception and product tolerability surveys were given to each patient.

OA improved wrinkle severity by 9.45% (p < 0.0001) at week 12, whereas retinol improved wrinkle severity by 4.11% (p < 0.001) compared to baseline. When comparing the two treatment groups, the OA group improved significantly more than the retinol group at week 8 (p = 0.095) and at week 12 (p = 0.001).

OA decreased pigment intensity at week 8 by 1.70% (p < 0.025) and week 12 by 3.88% (p < 0.0001). Retinol did not have any change at week 4 or week 8 but researchers observed decreased pigment intensity by 3.15% at week 12 (p < 0.03). Overall, OA-based improvement in pigment intensity at week 12 was not significantly different from retinol. 

Although there was no change at weeks 4 or 8, OA reduced facial erythema by 13.39% (p < 0.05) at week 12. The retinol group did not see a significant change at any follow-up. OA use led to a 14.92% decrease in TEWL by week 12 (p = 0.07), whereas the retinol group had no significant change. There were also no significant differences in skin hydration between the 2 groups.

Mild adverse events were assessed at follow-up visits and showed that OA was better tolerated than retinol. At week 12,5% reported burning and 10% reported scaling in the OA group. In comparison, 11% reported itching, 21% reported burning, 16% reported stinging, 21% reported scaling, and 21% reported redness in the retinol group. This correlates with previous research that has shown that adapalene is less irritating compared to other topical retinoids while providing the same clinical photoaging benefits.²

The investigators did note some limitations, such as the single trial site and the short duration. Further studies should expand the population with more variety of skin types and implement a longer study of 6 months to a year to test long-term results. More research could also consider how OA can be used to treat inflammatory conditions such as psoriasis and acne.

“These findings have important implications for the skincare industry, suggesting that OA may offer a more effective solution for addressing common cosmetic and photoaging concerns with a novel and emerging over-the-counter ingredient,” the authors wrote. “The promising results of this study pave the way for future investigations which may ultimately lead to better understanding of how OA can be utilized in the skincare and dermatology space.”

References

1. Nguyen N, Afzal N, Min M, et al. A prospective, double‐blinded, randomized head‐to‐head clinical trial of topical adapinoid (oleyl adapalenate) versus retinol. Skin Health and Disease. November 4, 2024. doi:10.1002/ski2.469

2. Sardana K, Sehgal VN. Retinoids: fascinating up-and-coming scenario. J Dermatol. 2003;30(5):355-380. doi:10.1111/j.1346-8138.2003.tb00402.x