A Pilot Study Using Reflectance Confocal Microscopy (RCM) in the Assessment of a Novel Formulation for the Treatment of Melasma

November 2011 | Volume 10 | Issue 11 | Original Article | 1260 | Copyright © November 2011

Katerina Tsilika,a Jean Luc Levy MD,c Hee Young Kang MD PhD,a Luc Duteil PhD,a Abdallah Khemis MD,a Rosalind Hughes MD,a Thierry Passeron MD PhD,a,b Jean Paul Ortonne MD,a Philippe Bahadoran MD PhDa,b

aDepartment of Dermatology, University Hospital of Nice, Nice, France bInstitut National de la Sante et de la Recherche Medicale (INSERM U895), Nice, France cCenter of Dermatological Lasers, Marseilles, France


Introduction:Melasma is a common pigmentary disorder caused by abnormal melanin deposits within the skin. Hydroquinone (HQ) is presently the most popular depigmenting agent, however the treatment of melasma remains unsatisfactory, resulting in a need to evaluate new depigmenting agents.
Objective: The objective of this study was to assess, using standard methods and a novel technique, in vivo Reflectance Confocal Microscopy (RCM), the efficacy and safety of a new non-HQ bleaching agent Dermamelan® (Mesoestetic, Barcelona, Spain) in the treatment of melasma.
Methods: Ten women with melasma were enrolled in an open-label trial lasting four months. Patients were of Fitzpatrick skin types II–IV. A non-HQ depigmenting agent (Dermamelan) was applied once-daily for three months. Melasma Area and Severity Indices (MASI) were measured. Standard and UV-light photographs were taken and in vivo RCM, which detects pigmentary changes at a cellular level, was done. Evaluations were performed before treatment, on the first, second and third month of treatment and one month after treatment. Upon cessation of the trial, patients completed a questionnaire regarding efficacy and tolerance.
Results: At baseline, RCM detected hyperpigmented keratinocytes in all patients, dendritic cells in 2/10 patients, and melanophages in 2/10 patients. Based on the MASI score, Dermamelan treatment improved melasma by 50 percent. This was confirmed by standard and UV-light photography. Maximum therapeutic effect was usually reached by one month of treatment and was maintained at one month following its completion. Interestingly Dermamelan treatment also induced a statistically significant decrease of pigmented epidermal keratinocytes as detected by RCM. Patients with melanophages on RCM at baseline had a poorer outcome, but not those with dendritic cells. Mild irritation was the only adverse event observed during treatment. The majority of patients were satisfied with the result.
Conclusion: This study suggests that Dermamelan produces significant rapid improvement of melasma at a clinical and cellular level and demonstrates the potential of RCM to monitor and possibly predict efficacy of a new depigmenting agent in the treatment of melasma.

J Drugs Dermatol. 2011;10(11):1260-1264.


Melasma is a common and disabling acquired hypermelanosis, most commonly affecting women, which presents as irregular brown-grey macules of the face. Aetiological factors include genetic predisposition, ultraviolet light exposure, and sex hormones.1 The pathogenesis of melasma is not yet fully understood. Two histological patterns of pigmentation are observed: an epidermal and a dermal pattern. In the epidermal type, melanin deposition is increased in basal and suprabasal keratinocytes. The dermal type is characterized by melanin deposition in perivascular melanophages. Both patterns may be seen in patients with mixed-type melasma.2 The efficacy of HQ and non-HQ in the treatment of melasma, is frequently unsatisfactory, notwithstanding the potential side-effects of hydroquinone.3,4 In vivo reflectance confocal microscopy (RCM) is a novel technique, which allows noninvasive imaging of the epidermis and the upper dermis at a near-histological resolution. Because melanin is the strongest endogenous contrast in human skin, pigmentary disorders are ideal for RCM examination. 5 In melasma, it has been shown that RCM accurately detects melanin distribution and in addition identifies the type of melanin-containing cells.6,7 RCM could therefore be very useful to evaluate new depigmenting agents. We conducted a clinical trial to evaluate the efficacy and safety of a novel non-hydroquinone formulation Dermamelan® (Mesoestetic, Barcelona, Spain) for the treatment of melasma, using RCM to monitor pigment changes within the skin.