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
Abstract
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.
INTRODUCTION
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.
