Efficacy and safety of dapsone gel for acne: a systematic review and meta-analysis

Background: First-line medications for acne vulgaris include retinoids and antibiotics. Dapsone is a topical drug approved by the U.S. Food and Drug Administration for the treatment of acne. However, due to its side effects, the clinical application of dapsone has not been promoted, and the value of the medication is still unclear. The aim of this study is to determine the efficacy and safety of dapsone gel in patients with acne. Methods: Systematic searches were performed using the following databases on January 4, 2020: PubMed, EMBASE, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure (CNICI), China Biomedical Literature Service System (SinoMed), China Science and Technology Journal Database (CQVIP), and Wanfang Data Knowledge Service Platform. A meta-analysis of randomized controlled trials was then conducted to analyze the efficacy and adverse events of dapsone gel treatment compared with excipient and other drug therapies. RevMan 5.3 software was used to calculate the odds ratio (OR), and the confidence interval (CI) was 95%. Results: Data of 11,424 participants across 7 trials which met the inclusion criteria were analyzed. Meta-analysis showed that dapsone gel alone or dapsone gel combined with isotretinoin was superior to excipient alone or oral isotretinoin alone in the treatment of acne (OR =1.51, 95% CI: 1.38-1.66, P<0.0001 random effects model, I-2 =0%). This indicates that dapsone gel is effective for the treatment of acne. We also found that dapsone gel is a more effective treatment for females (OR =1.80, 95% CI: 1.46-2.23). There was no significant difference in the incidence of adverse events between the dapsone group and the control group (OR =0.94, 95% CI: 0.82-1.14, P=0.24 random effects model; 1 2 =29%). The common local adverse reactions in the dapsone group, such as dryness, heat, and eczema, were not statistically significant compared with those in the control group, and the side effects were transient. Discussion: Dapsone gel is effective in treating acne, and there is no significant difference in adverse events compared with other drugs.