1599 Rapid reduction in S. aureus in atopic dermatitis subjects following dupilumab treatment

Atopic dermatitis (AD) is characterized by type 2 inflammation, chronic pruritus and Staphylococcus aureus (SA) skin colonization infections.SA thought to play a role in AD severity.We the changes host-microbial interface subjects following blockade. Participants (N=71) with moderate-severe were enrolled RDBPC study (dupilumab vs placebo; 2:1) at Dermatitis Research Network centers. Bioassays performed multiple timepoints: SA virulence factor quantification, 16s rRNA microbiome, serum biomarkers, barrier function, transcriptomic analyses PBMC phenotyping. Dupilumab treatment resulted significant reductions after only 3 days; 11 days before clinical improvement. Those greatest had best outcomes, correlated CCL17 reductions. Reductions cytotoxins (day 7), increases skin-homing Th17 subsets 14), increased expression of genes relevant for IL-17, neutrophil complement pathways 7) also observed. very rapidly reduced abundance which biomarker, CCL17. Immunoprofiling transcriptomics suggest immunity, while analysis points activation as potential mechanisms explain these findings.