In Vitro and In Vivo Efficacy and Tolerability of a Non-Hydroquinone, Multi-Action Skin Tone Correcting Cream

Background: Pigmentation disorders are therapeutically challenging to treat, requiring complicated regimens. Objectives: Alternatives to hydroquinone (HQ) are desired. We evaluated the efficacy and tolerability of a non-HQ multi-action skin tone corrector (ETCS) developed to inhibit melanin production and improve skin quality. Design and Methods: Twice-daily use of ETCS and ETCS + AHA-Ret, a retinoid-based alpha hydroxy acid cream, was evaluated in subjects with mild to severe dyschromia. Digital images were obtained at baseline, 4, 8, and 12 weeks and included assessment of dyschromia, erythema, fine lines/wrinkles, pores, texture, and global improvement. Melanin Index (MI) measurements were obtained at baseline, 4, 8, and 12 weeks. Subject self-assessments were obtained over the course of the study. Adverse Events (AEs) were collected throughout the study. An extension study evaluated use over 16-weeks. Results: Significant mean reductions from baseline occurred in dyschromia for ETCS (n=42) and ETCS + AHA-Ret (n=10) over 12 weeks (P<0.0001, each). Significant mean reductions from baseline in MI were achieved in both groups at every timepoint (ETCS: P<0.0001; ETCS + AHA-Ret: P<0.02, 4 weeks; P<0.0001, 8 and 12 weeks). Substantial improvements were demonstrated in global improvement, fine lines/wrinkles, erythema, pores, and texture at 12 weeks. Reductions from baseline occurred in dyschromia and MI (P<0.0001, each) at 16 weeks. High levels of subject satisfaction were reported with nearly all subjects reporting reduced appearance of uneven skin tone/discoloration and lightened darker patches, and improvement in overall skin tone. Mild, transient AEs were reported with no discontinuations due to an AE. Conclusions: Twice daily use of ETCS led to early, significant reductions in dyschromia and melanin index. Combination use with a retinoid-based, AHA cream in the evening demonstrated enhanced reductions. ETCS effectively reduced hyperpigmentation, improved overall skin appearance, and was highly tolerable. J Drugs Dermatol. 2019;18(7):642-648.