Do tutorials on application method enhance adapalene-benzoyl peroxide combination gel tolerability in the treatment of acne?

Fixed-dose combination adapalene 0.1% and benzoyl peroxide 2.5% gel (A-BPO) has rarely been studied for Asian acne patients, while they have complained of local irritations more often when applying individual components. In this study, we compared A-BPO gel with benzoyl peroxide (BPO) in terms of efficacy and tolerability in Korean patients first, and assessed the clinical benefit of a dermatological tutorial on application technique in reducing irritations for A-BPO. This study was conducted as a single-blind controlled split-face trial for a 12-week period. Each half facial side of 85 patients was randomly assigned to either A-BPO or BPO. Success rate, lesion counts and safety profiles were evaluated (analysis I). During initial assignment, all patients were further randomized to either dermatological tutorial (DT) or non-tutorial (NT) subgroups depending on the presence of dermatologists' tutorials for application methods to their A-BPO sides. Clinical data of the A-BPO side was compared between two subgroups (analysis II). As a result, A-BPO gel outperformed BPO, demonstrating better efficacy in success rates and lesion counts as early as 1week. However, A-BPO proved significantly less tolerable compared with both BPO and previous A-BPO data from Caucasians. Bioengineering measurements further confirmed clinical data (analysis I). The DT subgroup achieved much better tolerability with comparable therapeutic efficacies compared with the NT subgroup (analysis II). In conclusion, A-BPO demonstrated higher efficacies in acne compared with BPO in Korean patients, while skin irritation levels were notable concurrently. Dermatologists' education for application methods would significantly decrease these side-effects, maintaining superior efficacy levels.