Topical application of bacteriocins from Bacillus subtilis promotes Staphylococcus aureus decolonization in acneic skin and improves the clinical appearance of mild-to-moderate acne

Introduction: Patients with mild-to-moderate acne are frequently colonized by Staphylococcus aureus on their skin, which alters microenvironmental skin conditions and exacerbates disease symptoms. Bacteriocins produced by Bacillus subtilis may act as antimicrobial peptides against Gram-positive bacteria.Aim: To investigate whether topical application of bacteriocins from B. subtilis could serve as a potential strategy for promoting S. aureus decolonization from acneic skin.Material and methods: The research product was a cream formulation containing 1% bacteriocins from B. subti-lis. First, we conducted a 60-day pilot study on the effect of topically applied bacteriocins from B. subtilis on the absolute abundance of S. aureus in 12 patients with mild-to-moderate acne. Second, we designed an 8-week, un- controlled, open-label, multicentre clinical study to investigate whether the topical application of bacteriocins from B. subtilis reduces the number of inflammatory and non-inflammatory lesions, as well as Global Acne Grading Scale (GAGS) scores, in 373 patients with mild-to-moderate acne.Results: At the microbiological level, quantitative PCR showed a decrease in the absolute abundance of S. aureus in acne areas after topical application of the research product for 60 days (-38%, p < 0.001). In the clinical study, the number of inflammatory and non-inflammatory lesions was found to decrease at 8 weeks by 59% (p < 0.001) and 58% (p < 0.001), respectively, compared with baseline. A 56% decrease was observed for GAGS scores.Conclusions: Topical bacteriocins from B. subtilis can promote S. aureus decolonization in acneic skin, ultimately improving the clinical appearance of mild-to-moderate acne.