The discovery and development of omalizumab for the treatment of asthma

INTRODUCTION: The evolution in immunological methods used to assess human allergic diseases has led to the identification of immunoglobulin E (IgE) as a diagnostic biomarker and a potential therapeutic target. Innovative technologies in molecular biology and immunogenetics contributed to the development of a selective blocking agent, disclosing new therapeutic perspectives in the treatment of allergic asthma. Omalizumab is the most advanced humanized anti-IgE monoclonal antibody that specifically binds serum-free IgE. Omalizumab also interrupts the allergic cascade by preventing binding of IgE with FcεRI receptors on mast cells, basophils, antigen-presenting cells and other inflammatory cells. AREAS COVERED: This review discusses the discovery strategy and preclinical development of omalizumab. Furthermore, it also provides a clinical overview of the key trials leading to its launch and a detailed analysis of safety and post-marketing data. EXPERT OPINION: The clinical efficacy of omalizumab in allergic asthma has been well documented in clinical trials, involving adults, adolescents and children with moderate-to-severe and severe allergic asthma. To date, omalizumab has also been approved in chronic idiopathic urticaria for patients 12 years and older who remain symptomatic despite high dosages of H1 antihistamines. Omalizumab has also been investigated in many other different patient populations beyond allergic asthma and may yet have an application to other indications. While omalizumab is the only mAb available for treating allergic asthma, the authors anticipate that new mAbs will emerge in the future that overcome omalizumab's current limitations.