Background: Atopic dermatitis (AD) is a common chronic skin disease, and a significant percentage of AD patients have severe forms. Inflammation based on type 2 helper T cells (TH2), autoantibodies, and CD8+ T cells could play a relevant role in this disease. When the patient requires systemic immunosuppressors for disease control, side effects are frequent. We propose a sequential therapeutic strategy with 2 monoclonal antibodies, omalizumab (anti-immunoglobulin [Ig] E) and rituximab (anti-CD20), which might induce clinical benefit with few side effects in selected individuals with AD.

Methods: We report 6 cases of severe AD refractory to conventional therapy. The patients underwent sequential switch therapy with omalizumab and rituximab . Clinical response was assessed by means of the decrease in body surface affected. Immunological parameters and side effects were also monitored.

Results: Four patients received omalizumab before a high-dose cycle of rituximab. In the case of recurrences, either low-dose cycles of rituximab or omalizumab were administered. A long-term clinical benefit was observed in 3 out of 4 patients. Two patients fi rst received high-dose rituximab followed by either low-dose rituximab or omalizumab, and one of them achieved a response at 17 months. No severe side effects were recorded. Serum IgE level and B-cell counts decreased with therapy, the latter returning to baseline levels 10 to 11 months after treatment. Specific antibody responses remained protective during the study.

Conclusions: With our proposed switch therapy, 4 out of 6 patients achieved a dramatic clinical improvement. This novel strategy targets different arms of the immune response and might be a good alternative for patients with severe AD.

Key words: Atopic dermatitis. Omalizumab. Rituximab. Autoimmunity. Allergy.