A Method for Maintaining the Clinical Results of 4% Hydroquinone and 0.025% Tretinoin With a Cosmeceutical Formulation

April 2015 | Volume 14 | Issue 4 | Original Article | 386 | Copyright © April 2015


Zoe Diana Draelos MD,a Susana Raab BS,b Margarita Yatskayer MS,b Nannan Chen PhD,b
Yevgeniy Krol BS,c and Christian Oresajo PhDb

aDermatology Consulting Services, High Point, NC; Consulting Professor, Department of Dermatology, Duke University, Durham, NC
bL’Oréal Research and Innovation, Clark, NJ
cSkinceuticals, New York, NY

Abstract
Facial dyspigmentation treatment is an unmet need in dermatology with increasing challenges due to the questionable safety of hydroquinone. This research examined a new OTC formulation containing hydroxyphenoxy propionic acid, ellagic acid, yeast extract, and salicylic acid on subjects who previously completed 12 weeks of treatment with 4% hydroquinone and 0.025% retinoic acid. The goal of this study was to evaluate the skin lightening and tolerability profile of a 20-week maintanence therapy with a cosmeceutical formulation during the summer months. 33 healthy subjects ages 25-60 years with moderate facial dyspigmentation defined as a score of 3 on a 5-point scale were enrolled. There was statistically significant improvement at week 20 in terms of even skin tone (P<0.001), spot intensity (P<0.001), spot size (P<0.05) and overall hyperpigmentation (P=0.002).

J Drugs Dermatol. 2015;14(4):386-390.

INTRODUCTION

The treatment of facial dyspigmentation requires persistence and diligence on the part of the dermatologist and the patient. The current standard prescription therapy of 4% hydroquinone requires at least 3 months to obtain clinical results, but enhanced efficacy can sometimes be achieved by combining the 4% hydroquinone with 0.025% tretinoin.7 There is some controversy as to how long subjects can safely use hydroquinone and the barrier damage induced by combination therapy can decrease patient compliance.2 Further concerns regarding the safety of long-term hydroquinone use have been raised by both dermatologists and the FDA.8 These concerns have led researchers to examine other options that might allow initial treatment with hydroquinone followed by maintenance therapy with a cosmeceutical formulation. Hydroquinone inhibits melanin production by inhibiting tyrosinase, the key enzymatic step in melanin production.9 Its activity can be augmented by 0.025% tretinoin, which inhibits the transfer of melanin to keratinocytes, and also functions as a penetration enhancer for the hydroquinone through barrier degradation.6 The barrier degradation accounts for much of the peeling, stinging, and burning some subjects experience with combination treatment. This research examined the use of a novel hyperpigmentation formulation on subjects who have previously completed 12 weeks of treatment with 4% hydroquinone and 0.025% retinoic acid. This formulation contained hydroxyphenoxy propionic acid, ellagic acid, yeast extract, and salicylic acid. These active ingredients were specifically chosen to target different layers of the skin for more comprehensive disruption of the pigment pathway and pigment distribution. In a previous study, it was established that the novel formula attained equivalent clinical benefits as 4% hydroquinone and 0.025% tretinoin.1
Hydroxyphenoxy propionic acid inhibits melanin production from cultured B16 cells without affecting melanocyte viability.10 In addition, it inhibits melanosomes transfer to the keratinocytes. It is combined with ellagic acid, a naturally occurring compound found in fruits and berries, to block excess melanin production by inhibiting tyrosinase at the basal layer with an added function as an anti-inflammatory.11,12 Yeast extract, derived from saccharmoyces cerevisiae, functions in the stimulation of lysosomal degradation of keratinocytes to speed melanin degradation and removal while stimulating fibroblasts in the dermis aiding the skin’s resistance to formation of new pigment.13 Finally, salicylic acid functions as a penetration enhancer, while also exfoliating the skin to aid in the desquamation of existing pigment containing keratinocytes.
The goal of this study was to evaluate the skin lightening and tolerability profile of a 20-week maintanence therapy with a cosmeceutical formulation during the summer months. The primary objective was to determine the ability of the cosmeceutical formulation to maintain the attained reduction in hyperpigmentation parameters and offer additional improvements in skin quality as measured by a validated investigator assessment.