Ustekinumab treatment in severe atopic dermatitis: Down-regulation of T-helper 2/22 expression.

BACKGROUND: It has recently been suggested that patients with moderate to severe atopic dermatitis (AD) may profit from anti-interleukin (IL)-12/-23 p40 therapy. OBJECTIVE: We sought to assess the immunologic effects of ustekinumab treatment on AD skin and to correlate them with the clinical efficacy of this drug. METHODS: We investigated the course of 3 patients with severe AD who were administered 45 mg of subcutaneous ustekinumab over a period of 16 weeks. Clinical scores and skin biopsy specimens, taken at baseline and at week 8, were used to assess changes in disease severity. RESULTS: All patients showed a gradual improvement of the disease, achieving a 50% reduction in the Eczema Area and Severity Index score by week 16. Immunohistology of skin biopsy specimens revealed a significant decrease in the degree of epidermal hyperplasia/proliferation and the number of infiltrating dermal T cells, dendritic cells, and mast cells after treatment. Using quantitative real-time polymerase chain reaction of lesional skin, we found a clear reduction of T-helper 2-/22-associated molecules after therapy. LIMITATIONS: The small number of patients (n = 3) limits efficacy analysis and warrants prospective placebo-controlled studies in larger patient cohorts. CONCLUSION: Blocking IL-12/-23 p40 could be beneficial for a subgroup of patients with severely infiltrated AD.