Roseomonas mucosa

Roseomonas mucosa is a Gram-negative bacterium found on healthy human skin. In mice, strains taken from healthy volunteers improved eczema-like disease, while strains from people with eczema made it worse. This led NIH researchers to test it as a topical “microbiome transplant” for Atopic Dermatitis, a form of Bacteriotherapy (Myles, JCI Insight 2018).

Roseomonas mucosa [part-of] Skin Microbiome Roseomonas mucosa [part-of] Bacteriotherapy

Open-label trial (2018). Live R. mucosa in sugar water was applied twice weekly to 10 adults and 5 children aged 9–14 (16 weeks in children). There were no adverse events. 4 of 5 children improved by more than 50% on SCORAD, with less steroid use and less Staphylococcus aureus. There was no placebo arm, and the authors said placebo-controlled trials were needed. The study was later extended to children aged 3–17.

Roseomonas mucosa [opposes] Staphylococcus aureus SCORAD [relates] Roseomonas mucosa

Placebo-controlled trial (FB-401). The licensed product FB-401 contained 3 R. mucosa strains. In a 16-week double-blind RCT, 154 people aged 2 and over with mild-to-moderate AD applied FB-401 or placebo 3 times a week. About 58% on FB-401 and 60% on placebo reached the primary endpoint (EASI-50). There was no significant difference at any visit, and adverse events were similar in both arms (Dermatology 2024). EASI-90 (27.6% vs 20.5%) and IGA success (38.2% vs 29.5%) leaned towards FB-401, but these were non-significant secondary results. Forte Biosciences stopped development (Clinical Trials Arena 2021).

EASI [relates] Roseomonas mucosa

For toddlers. This is the only microbiome-transplant therapy tested in a placebo-controlled trial that included 2–4-year-olds, and it did not beat placebo. 60% of the placebo group also reached EASI-50, a reminder that uncontrolled reports of improvement can mislead. No product is on sale.

Roseomonas mucosa [relates] Atopic Dermatitis

Connections

• Skin Microbiome — first-in-human topical microbiome transplant, source: Myles JCI Insight 2018
• Bacteriotherapy — one of two commensal species trialled, source: Myles 2018
• EASI — EASI-50 primary endpoint not met, source: Dermatology 2024
• Staphylococcus aureus — lower S. aureus burden in open-label children, source: Myles 2018