Supramolecular salicylic acid combined with niacinamide in chloasma: a randomized controlled trial

Abstract Background Chloasma is a common skin hyperpigmentation condition, with treatment options ranging from topical agents to advanced interventions such as chemical peels and laser therapy. Salicylic acid, including its supramolecular form (SSA), has shown promise in managing chloasma. However, to date, no multicentre randomized controlled trial of SSA for chloasma is available. Objectives The purpose of this study was to assess the efficacy and safety of 30% SSA combined with 10% niacinamide in treating ­chloasma. Methods This multicentre (n = 15), randomized, double-blind, parallel placebo-controlled trial (Clinical trial registration number: ChiCTR2200065346) enrolled and randomized 300 participants (1 : 1) to either 30% SSA treatment or placebo, with 150 allocated to treatment and 150 to placebo in the full analysis set, and 144 to treatment and 147 to placebo in the per-protocol set. A Visia® Skin Analysis System was used at each visit to assess the degree of improvement in chloasma lesions. The primary endpoint was the effective rate after 16 weeks, assessed using the modified Melasma Area and Severity Index (mMASI) score [(pretreatment score − post-treatment score)/pretreatment score × 100%]. Results The total mMASI score, overall score on the Griffiths 10-point scale, and Griffiths 10 score for the left and the right sides of the face were significantly lower in the 30% SSA group than in the placebo group (all P < 0.001). One study of drug-related adverse events (AEs) and one study of drug-unrelated AEs were reported in the 30% SSA group. No AE was reported in the placebo group. Conclusions Among our patients, 30% SSA combined with 10% niacinamide was shown to be effective and safe for treating chloasma.