This interventional, randomized, investigator blinded, controlled study conducted in one centre consists in a 4-month evaluation period within the same season avoiding sunny season on 140 subjects with facial epidermal melasma.

Melasma is a very common pigmentation disorder which significantly alters quality of life as per its high visibility on the face. The objective is to compare the efficacy and tolerability of the new depigmenting formulation that addresses the different targets of hyperpigmentation and includes an inhibitor of melanin production with a breakthrough innovative mechanism of action versus Cysteamine 5% in the acute management of melasma over 4 months.

Statistics:

Sample size calculation: 120 patients (60 per group) are necessary to reach the non-inferiority objective of the Test Product versus Cysteamine 5% on the modified Melasma Area and Severity Index (mMASI) change from Baseline at Month 4. To allow a rate of subjects excluded from analysis (drop out, lost to follow-up, major deviation) at Month 4, 140 subjects in total (70 per group) are enrolled.

Statistical analysis: Continuous data collected at each visit will be summarized using common statistical measures such as the count of values, mean, standard deviation, median minimum and maximum. For categorical data, summaries will be provided in terms of frequency counts (n) and percentages (%).

Inclusion Criteria:

• Facial epidermal melasma (exclude mixed and dermal melasma)
• Subjects free of excessive hair, acne, cuts, abrasions, fissures, wounds, lacerations, or any other active skin conditions on the face

Exclusion Criteria:

• Subjects with any other signs of significant irritation or skin disease
• Subjects using oral contraceptive pills or hormonal implants as birth control measures during the study
• Subjects who had a skin lightening procedure in the past 8 weeks