Clinical efficacy and reflectance confocal microscopy monitoring in moderate-severe skin aging treated with a polyvinyl gel containing retinoic and glycolic acid: An assessor-blinded 1-month study proof-of-concept trial

Background: Retinoids and alpha-hydroxy acids are commonly used topically as anti-aging substances. Current medical devices contain retinoic acid (0.02%) and glycolic acid (4%) in a polyvinyl gel vehicle (R-G gel). There are still no clinical data nor objective evaluation of the anti-aging effect this product has in the short term. Aims: To assess in a prospective 1-month, noncomparative, primary outcome assessor-blinded proof-of-concept trial the clinical efficacy, tolerability, and the skin cells modification (evaluated through reflectance confocal microscopy; RCM), of R-G gel in skin aging treatment. Methods: Twelve women with moderate-severe skin aging (Glogau score ≥ 3) were enrolled. The product was applied on the face three times a week for 4 weeks. Study visits were performed at baseline and after 2 and 4 weeks. RCM evaluation was performed openly at each visit using Viva Scope 1500 to evaluate the left cheek (5 mm below the zygomatic process). Results: Eleven subjects concluded the trial. At baseline, the Glogau score was 3.4 ± 0.5 and decreased significantly at week 4 (P =.0001; ANOVA test) to 2.7 ± 0.6. Significant reductions of dark spots (−40%) and severity of wrinkles (−12%) were observed at week 4 compared to baseline. The RCM score improved significantly at week 4 with the recovery of the polygonal keratinocytes pattern as the central aspect observed. Conclusion: The gel containing retinoic acid and glycolic acid showed significant improvements of the clinical signs of severe skin aging with a concomitant improvement of epidermal and dermal structures evaluated via RCM.