Omalizumab Safety Concerns.

IgE and mast cells play key roles in the pathophysiology of allergic diseases, and omalizumab was the first monoclonal anti-IgE antibody licensed in the U.S. when initially FDA-approved for the treatment of allergic asthma in 2003. Since that time, the number of FDA-approved indications for treatment with omalizumab has grown to include chronic spontaneous urticaria, chronic rhinosinusitis with nasal polyps, and food allergy. Although omalizumab is generally considered relatively safe and well-tolerated, a number of safety concerns have been raised since its initial approval. These concerns focus on specific adverse events of interest that include anaphylaxis, pregnancy, malignancy, cardiovascular events, and infections. For each of these issues, data from clinical trials and post-marketing surveillance has been extensively evaluated. In this review, we examine this safety data, provide context for safety and risk assessments, and summarize a safety profile for each of the adverse events of interest. In doing so, we aim to provide a resource for shared-decision making when treatment with omalizumab is being considered.