Omalizumab in the treatment of severe persistent IgE-mediated asthma

Over 300 million people worldwide suffer from asthma, a chronic respiratory condition characterised by airway obstruction, inflammation and bronchial hyperresponsiveness. This figure is set to rise to 400 million by 2025. Despite a wide variety of treatment protocols and guidelines available for alleviation of symptoms, 5-10% of patients with asthma are non-responsive and are said to have severe, persistent (or refractory) asthma. These patients account for the majority of disease burden on the healthcare system in terms of mortality, morbidity and treatment costs. In approximately 50-80% of these patients, asthma is mediated by immunoglobulin E (IgE), which is critical in the inflammatory cascade. Omalizumab is a humanised monoclonal anti-IgE antibody used in the treatment of severe allergic asthma. It works by inhibiting cellular IgE binding and reducing the number of IgE receptors on pro-inflammatory cells. It has been shown to improve symptoms and quality of life, and reduce asthma exacerbations and the need for systemic corticosteroids. This review will look at the socioeconomic impact of severe allergic asthma on the Irish population and give a cost–benefit analysis of omalizumab and guidelines for its use in patients. Furthermore, it will discuss how to best optimise its use in the management of people with severe asthma, and illustrate the importance of critically reviewing trial data that is used to formulate and re-appraise guidelines in clinical practice.