Objective: To evaluate a combination of retinyl propionate and climbazole (RPC) compared to 0.1% retinol for its efficacy, tolerance and ageing appearance.
Method: Forty-five healthy Caucasian females, ages 40-70, with moderately photodamaged facial skin, were recruited for a 16-week randomized, double-blind, IRB-approved facial study. The efficacy of RPC treatment was compared to 0.1% retinol, in the same product base formulation, with twice daily, split-face product application. Changes in overall photodamage, fine lines and wrinkles, pigmentation and irritation were visually evaluated and measured by instrumentation. Subjective appraisal of efficacy was self-assessed from images where subjects were blinded to treatment and time point. Irritancy potential was also evaluated in a 5-day randomized, double-blind, IRB-approved patch study.
Results: Treatment with RPC resulted in significant (P < 0.05) improvement in ageing attributes compared to 0.1% retinol treatment, with minimal irritation. More than 50% of subjects showed improvement to deep wrinkles in the crow's feet area after 5 weeks of product application, and continued improvement to deep wrinkles was observed throughout the course of the study. Similarly, improvement was observed for the appearance of lines and wrinkles in the nasolabial fold (NLF) and for mottled hyperpigmentation. The results from subjective self-assessment confirmed in vivo clinical assessments. In a separate patch study, significantly less irritation was observed with the RPC product as compared to the 0.1% retinol control product.
Conclusion: RPC delivered significant skin anti-ageing benefits comparable or greater than 0.1% retinol, with minimal irritation.
Keywords: claim substantiation in vivo/in vitro; climbazole; formulation skin care; photoaging; retinoid.
© 2017 Society of Cosmetic Scientists and the Société Française de Cosmétologie.