Efficacy of a retinoid complex plus anti-inflammatory component cream alone or in combination with prebiotic food supplement in adult acne: A randomized, assessor-blinded, parallel-group, multicenter trial on 184 women

Background Adult female acne (AFA) nowadays is a very common skin condition affecting mainly women aged between 25 and 40. The treatment of AFA could be challenging. Study aim We evaluate and compare the efficacy and tolerability of a cream formulation containing two retinoid molecules (hydroxypinacolone/retinyl palmitate) combined with Iris Florentina root extract and a complex of three oligopeptides (C) applied twice a day (morning and evening) alone or in combination (C + O) with a food supplement containing a mixture of prebiotic molecules (FOS&GOS) zinc, lactoferrin, and niacinamide. Subjects and methods In a multicenter, randomized, assessor-blinded, 12-week trial, we assessed the efficacy of these two regimens in the evolution of AFA lesions (non-inflammatory: NI-L; inflammatory: IL; and total number of lesions: TL). Additional efficacy endpoints were the evolution of the 6-point (from 0 to 5) GEA and Adult Female Acne Scoring Tool (AFAST) scores. Results One hundred and eighty-four women (mean age 32 +/- 6 years) with AFA agreed to participate after obtaining informed consent. They were randomized (2:1) to the topical product (n = 123) (Group C) or to the combination (n = 61) (Group C + O) treatment. All enrolled patients concluded the trial with no drop-out. At baseline, NI-L, IL, and TL acne lesion count were 15 +/- 9, 9 +/- 5, and 24 +/- 14 in the Group C and 19 +/- 8, 9 +/- 4, and 29 +/- 10 in Group C + O. In comparison with the number of the acne lesions at the baseline, both treatment regimens induced a significant reduction (p = 0.0001, ANOVA test) at Week 12 in NI-L, IL, and TL by -54%, -63%, and - 59% in Group C and by -55%, -73%, and - 61% in the Group C + O, respectively. At Week 12, the absolute IL count reduction vs. baseline was significantly (p = 0.0158) greater in Group C + O (-7.0) in comparison with Group C (-5.5). The GEA absolute score reduction in Group C + O group was significantly greater in comparison with Group C (-1.5 vs. -1.1; p = 0.0097). In the Group C + O, a greater percentage of success treatment (defined as a GEA score of 0/1 at Week 12) was observed in comparison with Group C (39% vs. 27%; p = 0.06). AFAST score at baseline was 2.4 +/- 0.5 in group C and 2.8 +/- 0.6 in group C + O. AFAST score was reduced by 21% and by 51% after 6 and 12 weeks of treatment in group C and by 22% and 55% in group C + O, respectively. Both treatment regimens were well tolerated. Not relevant adverse events were recorded. Conclusion A cream containing retinoid molecules and Iris Florentina root extract is effective and well tolerated in the management of AFA. The treatment combination with a prebiotic and anti-inflammatory food supplement offers an additional clinical benefit mainly in reducing inflammatory lesions and improving the severity acne score.