COMPARISON OF A COSMETIC SERUM AND 4% HYDROQUINONE FOR TREATING MELASMA OVER 84 DAYS

Participants in Group 1 receive a depigmenting cosmetic serum with non-drug actives applied morning and evening, plus a placebo cream without hydroquinone applied in the evening. Group 2 receives a placebo serum (no active depigmenting ingredients) applied morning and evening, and a hydroquinone 4% cream applied in the evening. All participants apply an SPF50+ sunscreen in the morning throughout the 84-day study. The cosmetic serum is the investigational product; hydroquinone serves as the active comparator. Placebo products are visually matched to their respective actives to ensure blinding. The study distinguishes each intervention by active ingredients, timing of application (morning/evening), and role (test vs. reference vs. supportive care). All products are applied topically, and the regimen remains fixed across the study duration.