Andrew Cooke, Adeeb Bulkhi, Thomas B Casale

Chronic urticaria (CU) is a common condition faced by many clinicians. CU has been estimated to affect approximately 0.5%-1% of the population, with nearly 20% of sufferers remaining symptomatic 20 years after onset. Antihistamines are the first-line therapy for CU. Unfortunately, nearly half of these patients will fail this first-line therapy and require other medication, including immune response modifiers or biologics. Recent advances in our understanding of urticarial disorders have led to more targeted therapeutic options for CU and other urticarial diseases. The specific biologic agents most investigated for antihistamine-refractory CU are omalizumab, rituximab, and intravenous immunoglobulin (IVIG). Of these, the anti-IgE monoclonal antibody omalizumab is the best studied, and has recently been approved for the management of CU. Other agents, such as interleukin-1 inhibitors, have proved beneficial for Schnitzler syndrome and cryopyrin-associated periodic syndromes (CAPS), diseases associated with urticaria. This review summarizes the relevant data regarding the efficacy of biologics in antihistamine-refractory CU.