Impact of IL-4/IL-13 Blockade with Dupilumab on the Microbiome in Type 2 Inflammatory Diseases: A Systematic Review.

PURPOSE OF REVIEW: To systematically review current evidence on microbiota changes associated with dupilumab treatment across different anatomical sites in type 2 inflammatory diseases.

RECENT FINDINGS: Fifteen studies were included, comprising two randomized trials and thirteen observational studies, mostly in atopic dermatitis, with fewer data in chronic rhinosinusitis with nasal polyps and NSAID-exacerbated respiratory disease. The skin was the most frequently investigated site, followed by the sinonasal tract and gut. Across skin studies, dupilumab was consistently associated with reduced Staphylococcus aureus, increased microbial diversity, and enrichment of commensal taxa. Sinonasal studies suggested shifts toward more eubiotic microbial communities. Gut evidence was limited, although one study suggested modulation of tryptophan metabolism-related pathways.  Dupilumab appears to exert compartment-specific and disease-dependent effects on the microbiome. The strongest evidence concerns the skin and sinonasal compartments, whereas gut microbiota changes remain poorly defined. Further prospective studies are needed to assess microbiota signatures as potential biomarkers of response.