Chronic spontaneous urticaria (CSU) is characterized by the recurrence of itchy hives and/or angioedema for greater than six weeks, with no known external trigger. Omalizumab, a humanized, recombinant, monoclonal anti-IgE antibody, is the only approved add-on therapy for H1-antihistamine refractory CSU patients. Areas covered: The objective of this article is to discuss the mechanism of action, pharmacokinetics and pharmacodynamics of omalizumab for the treatment of CSU. The review also summarizes efficacy and safety data from proof-of-concept, phase II (X-CUISITE, MYSTIQUE), and pivotal phase III omalizumab studies (ASTERIA I, ASTERIA II, and GLACIAL). Expert opinion: Omalizumab is a clinically effective and safe biological therapy for treating H1-antihistamine refractory CSU patients. It significantly reduces CSU symptoms (hives, itch and angioedema), and improves patient health-related quality of life. While omalizumab is already integral to the treatment of antihistamine refractory CSU, widespread use will depend on legal and economic factors, as well as improvements in the early and accurate diagnosis of CSU patients who would benefit from treatment.
Keywords: Anti-IgE; chronic idiopathic urticaria; chronic spontaneous urticaria; chronic urticaria; omalizumab.