Histological features of immune cell infiltrate in lesional skin correlate with therapeutic response to dupilumab.

In the last decade, dupilumab, a monoclonal human antibody inhibiting IL-4/IL-13 signaling, has revolutionized the therapeutic management of moderate-to-severe atopic dermatitis (AD), permitting a long-term control of its signs and symptoms. The aim of this study was to identify histologic predictors of dupilumab efficacy after 16 weeks of treatment in a cohort of forty adult patients with moderate to severe AD who had undergone a skin biopsy for diagnostic purposes prior to treatment initiation. We found that EASI 75 and EASI 90 responses at week 16 were significantly associated with perivascular localization (OR=17.6, p=0.038) and lichenoid distribution (OR=31.8, p=0.025) of the immune infiltrate. Moreover, for each unit increase in the number (cells/m2) of CD4+ cells, the likelihood to achieve EASI75 response decreased by 1% (OR=0.99, p=0.037). In conclusion our study suggested a few pre-treatments qualitative and quantitative immunohistochemical features as promising markers predicting dupilumab response in AD patients.