Report of two sisters with Netherton syndrome successfully treated with dupilumab and review of the literature.

Different monoclonal antibodies have been used for the treatment of Netherton's syndrome (NS); secukinumab (anti-IL17A), infliximab (anti-TNF-α), ustekinumab (anti p40 subunit of IL-12 and IL-23), omalizumab (anti-IgE), and dupilumab (anti-IL4 and IL13). We report two sisters with severe NS who were treated with omalizumab in one and with secukinumab in the other. In view of the therapeutic failure, treatment with dupilumab was started in both sisters. The data were analyzed 16 weeks after starting treatment with dupilumab. Treatment response was assessed using the Severity Scoring Atopic Dermatitis (SCORAD); Eczema Area and Severity Index (EASI); Pruritus Numeric Rating Scale (NSR); Netherton Area Severity Assessment (NASA) and Dermatology Life Quality Index Ichthyosis. All scores were reduced after 16 weeks of treatment with dupilumab in both patients. She maintains improvement after 18 months and 12 months of treatment, respectively. No severe adverse events were reported. Treatment with dupilumab in two sisters with NS and atopic diseases produced a marked cutaneous improvement after a failed attempt with omalizumab and secukinumab. Further studies are needed to determine which biologic therapy is the most effective in NS.