Clinical efficacy and safety of benzoyl peroxide for acne vulgaris: Comparison between Japanese and Western patients.

Benzoyl peroxide (BPO) has been well established as a common medication for acne vulgaris in many countries (e.g. in Europe and the USA), where clinical data have been accumulated over a long time. In Japan, the use of BPO for acne treatment was approved in 2014, and the results of clinical trials in Japanese patients have recently been reported. This review compares clinical study results between Japanese and Western patients. Clinical studies that had been performed in Western countries were searched on the basis of the criteria, double-blind studies of BPO monotherapy and comparison with a vehicle group. Two reports of Japanese studies were also selected by using the same criteria. Efficacy was assessed by comparing the mean difference between the BPO and the vehicle groups for reduction rate in the number of lesions from baseline, and there were no differences between Japanese and Western patients. Safety assessment also showed that the incidence of adverse events was higher in Japanese patients than in Western patients, but the characteristics of the adverse events were not different. Therefore, we conclude that there are no significant differences in the efficacy and safety of BPO between these patient populations. The efficacy and safety of long-term use in Japanese patients are also expected to be applicable to those in Western patients.

Twelve-week, multicenter, placebo-controlled, randomized, double-blind, parallel-group, comparative phase II/III study of benzoyl peroxide gel in patients with acne vulgaris: A secondary publication.

A placebo-controlled, randomized, double-blind, parallel-group, comparative, multicenter study was conducted to investigate the efficacy and safety of benzoyl peroxide (BPO) gel, administrated once daily for 12 weeks to Japanese patients with acne vulgaris. Efficacy was evaluated by counting all inflammatory and non-inflammatory lesions. Safety was evaluated based on adverse events, local skin tolerability scores and laboratory test values. All 609 subjects were randomly assigned to receive the study products (2.5% and 5% BPO and placebo), and 607 subjects were included in the full analysis set, 544 in the per protocol set and 609 in the safety analyses. The median rates of reduction from baseline to the last evaluation of the inflammatory lesion counts, the primary end-point, in the 2.5% and 5% BPO groups were 72.7% and 75.0%, respectively, and were significantly higher than that in the placebo group (41.7%). No deaths or other serious adverse events were observed. The incidences of adverse events in the 2.5% and 5% BPO groups were 56.4% and 58.8%, respectively; a higher incidence than in the placebo group, but there was no obvious difference between the 2.5% and 5% BPO groups. All adverse events were mild or moderate in severity. Most adverse events did not lead to study product discontinuation. The results suggested that both 2.5% and 5% BPO are useful for the treatment of acne vulgaris.

Open-label, randomized, multicenter, phase III study to evaluate the safety and efficacy of benzoyl peroxide gel in long-term use in patients with acne vulgaris: A secondary publication.

An open-label, randomized, multicenter study was conducted to evaluate the safety and efficacy of long-term use of 2.5% and 5% benzoyl peroxide (BPO) gels administrated once daily for 52 weeks to Japanese patients with acne vulgaris. The efficacy of the study drugs was evaluated by counting inflammatory lesions and non-inflammatory lesions. Safety was evaluated based on adverse events, local skin tolerability scores and laboratory test values. In total, 458 subjects were included in the efficacy and safety analyses. The total lesion count, the efficacy end-point, was similarly changed both in the 2.5% and 5% BPO groups over the course of the study. The median rates of reduction from baseline to week 12 were approximately 65%. Thereafter, the counts were maintained at a reduced level without increasing until week 52. The median rates at week 52 were approximately 80%. Similar trends were observed for inflammatory and non-inflammatory lesion counts. Bacteriological evaluation indicated similar distribution of the minimum inhibitory concentration of each of the antibacterial drugs against Propionibacterium acnes between the values at baseline and at week 52, suggesting that long-term use did not result in changes in the drug sensitivity. The incidence of adverse events was 84.0% in the 2.5% BPO group and 87.2% in the 5% BPO group. Many of the adverse events occurred within the first month and were mild or moderate in severity and transient. The results suggest that both 2.5% and 5% BPO gels are effective and safe for long-term treatment of patients with acne vulgaris.