Novel retinoid ester in combination with salicylic acid for the treatment of acne.

BACKGROUND Retinoids (RC), alpha-hydroxy acids (AHA), and salicylic acid (BHA) treat acne through differing mechanisms of action. It is theorized that optimal improvement can be achieved by combining the RC-induced normalization of cellular differentiation, AHA-induced exfoliation in hydrophilic areas, and BHA-induced exfoliation in lipophilic areas. AHA and RC have been combined in a bioengineered molecule (AHA retinoid conjugate, or AHA-RC) delivering both lactic acid (AHA) and RC in a manner reducing retinoid-associated irritation. OBJECTIVES To evaluate efficacy and tolerability of a twice-daily, three-product skincare regimen using AHA-RC in combination with BHA for patients with acne. METHODS A total of 27 women (age range 20-58 years, mean 37.81 ± 10.04 years) with mild-to-moderate acne used a 3-product regimen consisting of a twice-daily cleanser and topical serum (0.1% AHA-RC, 2% salicylic acid, and 10.4% l-lactic acid), with broad-spectrum SPF 50+ sunscreen as needed, over an 8-week period. Counts were made at baseline, week 4, and week 8 of total inflammatory (papules, pustules) and noninflammatory (open comedones, closed comedones) lesions. Dryness, stinging, and other secondary endpoints were rated on a 0-5 scale. RESULTS Statistically significant reduction in inflammatory and noninflammatory lesion counts (P = 0.006 and P = 0.015, respectively) was noted at 4 weeks. Improvement continued into week 8 with highly significant (P < 0.001) reductions in both lesion counts. CONCLUSIONS The topical combination of lactic acid, SA, and AHA-RC produced acne improvement after 4 weeks with continuing cumulative improvement at 8 weeks. AHA-RC represents a new molecule combining several mechanisms of action to achieve acne improvement.