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

Over the past decade, dupilumab, a monoclonal human antibody that inhibits interleukin (IL)-4 and IL-13 signalling, has revolutionized the therapeutic management of moderate-to-severe atopic dermatitis (AD), facilitating long-term control of its signs and symptoms. The aim of this study was to identify histological predictors of the efficacy of dupilumab after 16 weeks of treatment in a cohort of 40 adults with moderate-to-severe AD who had undergone a skin biopsy for diagnostic purposes before treatment initiation. We found that Eczema Area and Severity Index (EASI) 75 and EASI 90 responses at week 16 were significantly associated with perivascular localization [odds ratio (OR) 17.6; P = 0.04] and lichenoid distribution (OR 31.8; P = 0.03) of the immune infiltrate. Moreover, for each unit increase in the number (cells mm-2) of CD4+ cells, the likelihood of achieving an EASI 75 response decreased by 1% (OR 0.99; P = 0.04). In conclusion, our study found promising pretreatment immunohistochemical markers that could predict how well patients with AD respond to dupilumab.