Topical preparations for the treatment of mild to moderate acne vulgaris: systematic review and network meta‐analysis

Background Acne is very common and can have substantial impact on wellbeing. Guidelines suggest first line management with topical treatments but there is little evidence regarding which are most effective. Objectives To identify the most effective and best tolerated topical treatments for acne using network meta-analysis. Methods CENTRAL, MEDLINE, EMBASE and WHO Trials Registry were searched until June 2020 for randomised trials that included participants with mild/moderate acne. Primary outcomes were self-reported improvement in acne, and trial withdrawal. Secondary outcomes included change in lesion counts, Investigator Global Assessment, change in quality of life and total number of adverse events. Network meta-analysis was undertaken using a frequentist approach. Risk of bias was assessed using the Cochrane Risk of Bias Tool and confidence in evidence with CINeMA. Results A total of 81 papers were included, reporting 40 trials including 18,089 participants. Patient Global Assessment of Improvement was reported in 11 trials. Based on the pooled network estimates, compared with vehicle, benzoyl peroxide (BPO) was effective (35% v 26%, odds ratio (OR) 1.93, 95% confidence interval (CI) 1.45- 2.56; moderate confidence) for improving self-reported acne. The combinations of BPO with adapalene (54% v 35%, OR 1.88, 1.32-2.67; low confidence) or with clindamycin (49% v 35%; OR 1.54, 1.14-2.08; low confidence) were ranked more effective than BPO alone. Participants withdrawing from the trial was reported in 35 trials. Numbers withdrawing due to adverse events were low for all treatments. Rates of withdrawal were slightly higher for BPO with adapalene (2.5%) or clindamycin (2.7%) than BPO (1.6%) or adapalene alone (1.0%). Overall confidence in the evidence was low. Conclusions Adapalene+BPO may be the most effective but with a slightly higher incidence of withdrawal than monotherapy. Inconsistent reporting of trial results precluded firmer conclusions.