Two 12-week, randomized, vehicle-controlled. double-blinded pivotal studies and a 12-month. long-term, open-label, noncomparative safety study were conducted to evaluate the efficacy and safety of dapsone gel 5% in patients with acne vulgaris. Of 3516 participants enrolled in the 3 trials, 1306 participants (37%) were adolescents aged 12 to 15 years and comprised the subgroup reported here. Participants randomly were assigned to twice-daily treatment with dapsone gel (n=578) or vehicle gel (n=547) in the pivotal studies and received open-label treatment with dapsone gel in the long-term safety study (n=181). In the pivotal studies, success based on achieving a Global Acne Assessment Score (GAAS) of 0 (none) or 1 (minimal) at week 12 was significantly greater for the dapsone gel-treated adolescent participants (40.1%; 232/578) compared with the vehicle gel-treated adolescent participants (28.2%; 154/547) (P<.001). Treatment with dapsone gel in adolescents also resulted in clinically meaningful improvements in acne lesion counts by week 12 in the pivotal studies and for up to 12 months in the long-term safety study. The incidence of adverse events, including application-site events, was low and similar between treatment groups in the pivotal studies and was similarly low in the long-term safety study. Results from the large number of adolescent participants in these 3 studies show that dapsone gel is an effective and safe topical therapy for the treatment of acne vulgaris in adolescents aged 12 to 15 years for up to 12 months.