Abstract: 【Abstract】 Objective To evaluate clinical efficacy and safety of calcium-based antimicrobial peptide compounds cooling gel （CAPCS cooling gel） in the treatment of atopic dermatitis （AD）. Methods A randomized, double-blind, active-controlled clinical study was conducted. From July 2019 to May 2020, 80 adult patients with mild-to-moderate AD were enrolled from Beijing Friendship Hospital, Capital Medical University, and randomly and equally divided into 2 groups: test group topically treated with CAPCS cooling gel, control group topically treated with hydrocortisone cream, and the treatment was performed thrice a day for 4 consecutive weeks. Before, 1, 2 and 4 weeks after the start of treatment, efficacy was evaluated according to the Eczema Area and Severity Index （EASI）, Visual Analog Scale （VAS）, and Investigator′s Global Assessment （IGA） scores, and adverse events were recorded. Efficacy and safety were compared by using repeated measures analysis of variance and chi-square test. Results Of the 80 patients with AD, 43 were males and 37 were females, and the age was 52.71 ± 16.71 years. Before the treatment, there was no significant difference in gender, age, EASI, VAS or IGA scores between the two groups （all P > 0.05）. After 1- and 2-week treatment, there was no significant difference in the response rate between the test group （10.00% ［4/40］, 57.50% ［23/40］, respectively） and control group （15.00% ［6/40］, 52.50% ［21/40］ respectively, both P > 0.05）. After 4-week treatment, the response rate was significantly higher in the test group （82.50%, 33/40） than in the control group（57.50%, 23/40, P < 0.05）. Compared with the control group, the test group showed significantly decreased VAS scores after 1-, 2- and 4-week treatment（U = 1253.00, 1121.00, 1091.50, respectively, all P < 0.05）. No drug-related adverse events were observed in either of the groups. Conclusion CAPCS cooling gel is safe and effective in the treatment of mild-to-moderate AD in adults, and can be applied in clinic.

Key words: Dermatitis, atopic, Bandages, hydrocolloid, Antimicrobial cationic peptides, Hydrocortisone, Treatment outcome