Effects of omalizumab treatment on serum cytokine concentrations of atopic patients with chronic spontaneous urticaria: A preliminary report

Abstract

Omalizumab has recently obtained indication for chronic spontaneous urticaria both in the US and Europe. However, the mechanism of action of this drug has yet to be fully elucidated. Previous studies have shown elevations in cytokine serum levels in patients with chronic spontaneous urticaria, and it is not known whether omalizumab treatment may affect cytokine serum levels in this condition. Besides, a proportion of chronic spontaneous urticaria patients have concomitant atopy, which may be associated, at least in theory, with prevalence of serum Th2-type cytokines. In this study, serial serum samples from five patients (4 atopic and 1 nonatopic) with chronic spontaneous urticaria were assayed for cytokine concentrations by means of flow-cytometry-based multiplex bead assays, before and during omalizumab treatment. Omalizumab appeared to significantly affect the concentrations of multiple cytokines in a case of severe, long-lasting chronic spontaneous urticaria. Interestingly, IL-22 serum levels were found to progressively increase in three of five patients. Further studies are thus needed in larger patient populations, to conclusively establish whether the mechanism of action of omalizumab in chronic spontaneous urticaria also includes modulation of cytokine synthesis.