Objective: To assess the maintenance effect of adapalene gel, 0.1%, relative to gel vehicle in subjects successfully treated in a previous 12-week study of adapalene-doxycycline, 100 mg, combination therapy.
Design: Multicenter, investigator-blind, randomized, controlled study.
Setting: Thirty-four US centers.
Subjects: A total of 253 subjects with severe acne vulgaris who showed at least moderate improvement from baseline (50% improvement from baseline) when treated with either adapalene plus doxycycline or doxycycline plus gel vehicle in a previous 12-week study.
Interventions: Subjects were randomized to receive adapalene gel, 0.1%, or gel vehicle once daily for 16 weeks.
Main outcome measures: Efficacy and safety criteria included maintenance rate (subjects maintaining at least 50% improvement in lesion counts from previous therapy), lesion counts (total, inflammatory, and noninflammatory), global severity assessment, cutaneous tolerability, and adverse events.
Results: Adapalene maintenance therapy resulted in significantly larger maintenance rates (75% vs 54%; P<.001) and significantly lower lesion counts (total [P = .005], inflammatory [P = .01], and noninflammatory [P = .02]) compared with gel vehicle. Adapalene was safe and well tolerated in this study. Conclusion This study demonstrates a clinical benefit of continued treatment with adapalene gel, 0.1%, as a maintenance therapy for acne.