Improved efficacy and tolerability of retinoic acid in acne vulgaris: a new topical formulation with cyclodextrin complex ψ

OBJECTIVES: Retinoic acid (RA) has long been used, both topically and systemically, for disorders of keratinization, acne and related disorders. In the present study, the efficacy and tolerability of topical RA prepared as a cyclodextrin beta complex (beta-CD) is investigated in 66 acne vulgaris patients. METHODS: This randomized, double-blind, placebo-controlled study compares nightly topical application of RA/beta-CD complex hydrogel formulation (0.025%), RA/beta-CD complex in moisturizing base (0.025%), hydrogel base, moisturizer base or a commercial RA gel (0.05%) in acne vulgaris patients. Improvement of acne was assessed using a 5-point improvement scale and by measuring sebum and moisture content of the skin using an SM 810 sebumeter/corneometer. RESULTS: After 3 months of treatment, mean scores of acne improvement on the 5-point scale were 4 with the RA/beta-CD complex hydrogel formulation, 4.1 with the RA/beta-CD complex in moisturizing base, 1.2 with hydrogel placebo base, 1.1 with moisturizer placebo base and 3 with the commercial RA product. All patients treated with the commercial product experienced local side-effects. One patient discontinued due to severe irritation. None of the patients treated with the RA/beta-CD complex in the moisturizing base and hydrogel formulation experienced significant local irritation, although the sebum content of the skin decreased after application of the RA/beta-CD preparations. This change was not significant compared to controls. The moisture content of the skin was better preserved in the group treated with the RA/beta-CD complex in the moisturizing base. CONCLUSION: The topical RA/beta-CD complex, in hydrogel and moisturizing base, was more effective than the twice concentrated commercial RA product. There were few topical side-effects with this new formulation, which increases patient compliance. Topical RA/beta-CD (0.025% RA) did not significantly reduce sebum secretion but may help to preserve optimum epidermal moisture content with the proper base formulation. This is the first study in the literature reporting efficacy and tolerability of the topical RA/beta-CD complex in acne vulgaris. We conclude that the topical RA/beta-CD complex displays an improved efficacy and tolerability profile and is an effective treatment alternative for acne vulgaris.