Abstract: Li Yong, Xian Yan, Li Li. Department of Dermatology, West China Hospital, Sichuan University, Chengdu 610041, China Corresponding author: Li Li, Email: lilihx_scu@scu.edu.cn 【Abstract】 Objective To evaluate the clinical efficacy and safety of two glycolic acid-containing liquid preparations for the treatment of facial acne vulgaris. Methods Sixty patients with mild to moderate acne vulgaris were included in a randomized, single-blinded, split-face, controlled study. The left and right sides of each patient′s face were randomly assigned to the test group （treated with one hydroxy acid-containing liquid preparation） and control group （treated with the other hydroxy acid-containing liquid preparation）. In total, all the patients were given four times of treatment at week 0, 2, 6 and 10 with the concentration of hydroxy acid in both preparations being 20%, 35%, 50% and 70%, respectively. The number of inflammatory and noninflammatory acne lesions was counted, and the improvement in acne mark, scar and pores was evaluated by a 6-point grading scale before every treatment and 4 weeks after the last treatment. Results At 2, 6, 10, and 14 weeks after initiation of treatment, the clearance rate for inflammatory lesions was 20.4%, 43.3%, 66.9% and 80.2% respectively in the test group, 21.6%, 44.2%, 68.1% and 79.8% respectively in the control group, while that for noninflammatory lesions was 18.5%, 34.0%, 41.3% and 59.6% respectively in the test group, 17.8%, 31.2%, 44.9% and 57.1% respectively in the control group. The response rate was 80.0% in the test group and 78.3% in the control group at the end of the study. Adverse effects were observed in both groups, including temporary pain, erythema and formation of hoar frost, all of which well responded to symptomatic treatment. There were no significant differences in clinical efficacy or adverse effects between the two groups （both P > 0.05）. Conclusion Both of the hydroxy acid-containing preparations are effective and safe for mild to moderate acne vulgaris.

Key words: Acne vulgaris, Glycolic acid, Treatment outcome