Lack of improvement after short-term topical antistaphylococcal endolysin SA.100 therapy in patients with...

Area of Science:

• Dermatology
• Microbiology
• Immunology

Background:

• Atopic dermatitis (AD) is a chronic inflammatory skin condition often associated with Staphylococcus aureus (S. aureus) overgrowth and reduced microbial diversity.
• S. aureus colonization affects 70%-90% of AD patients, contributing to disease severity.
• Novel therapeutic strategies targeting S. aureus are needed for AD management.

Purpose of the Study:

• To evaluate the safety, pharmacodynamics, and efficacy of SA.100, a novel recombinant endolysin, as a topical treatment for mild-to-moderate atopic dermatitis.
• To assess the impact of SA.100 on S. aureus colonization and skin microbiome composition.
• To determine the clinical benefit of SA.100 in improving AD symptoms and patient-reported outcomes.

Main Methods:

• A double-blind, randomized, vehicle-controlled trial was conducted with 53 subjects diagnosed with mild-to-moderate AD.
• Participants were randomized to receive either topical SA.100 or a vehicle control, stratified by S. aureus positivity.
• Safety, S. aureus levels, microbiome features, clinical outcomes, and patient-reported outcomes were assessed over a 2-week treatment period.

Main Results:

• Topical SA.100 was demonstrated to be safe and well-tolerated in the study population.
• No statistically significant reduction in S. aureus colonization was observed in the SA.100 group compared to vehicle.
• No significant changes in skin microbiome features, clinical AD severity scores, or patient-reported outcomes were detected after 2 weeks of treatment.

Conclusions:

• Topical SA.100 is safe and well-tolerated for patients with mild-to-moderate atopic dermatitis.
• Short-term treatment with SA.100 did not effectively reduce S. aureus colonization or improve clinical outcomes in AD.
• Current findings do not support the short-term clinical application of topical SA.100 for mild-to-moderate AD.