Sunscreens with the New MCE Filter Cover the Whole UV Spectrum: Improved UVA1 Photoprotection In Vitro and in a Randomized Controlled Trial

Abstract

Background: UVA1 rays (340–400 nm) contribute to carcinogenesis, immunosuppression, hyperpigmentation, and aging. Current sunscreen formulas lack sufficient absorption in the 370–400 nm wavelengths range. Recently, a new UVA1 filter, Methoxypropylamino Cyclohexenylidene Ethoxyethylcyanoacetate (MCE) exhibiting a peak of absorption at 385 nm, was approved by the Scientific Committee on Consumer Safety for use in sunscreen products. These studies evaluated, in a three-dimensional skin model and in vivo, the protection afforded by state-of-the-art sunscreen formulations enriched with MCE. Trial design: This study is a monocentric, double-blinded, randomized, and comparative trial. This study is registered at ClinicalTrials.gov with the identification number NCT04865094. Methods: The efficacy of sunscreens with MCE was compared with that of reference formulas. In a three-dimensional skin model, histology, protein, and gene expression were analyzed. In the clinical trial, pigmentation was analyzed in 19 volunteers using colorimetric measurements and visual scoring. Results: MCE addition in reference formulas enlarged the profile of absorption up to 400 nm; reduced UVA1-induced dermal and epidermal alterations at cellular, biochemical, and molecular levels; and decreased UVA1-induced pigmentation. Conclusions: Addition of MCE absorber in sunscreen formulations leads to full coverage of UV spectrum and improved UVA1 photoprotection. The data support benefits in the long term on sun-induced consequences, especially those related to public health care issues.