Asthma is distinguished by airway inflammation and reversible airflow restriction. Severe asthma affects 5 to 10% of asthmatic patients yet accounts for more than half of asthma treatment costs in the United States. There is a growing interest in defining and managing this complex population. Although inhaled corticosteroids and bronchodilators are the foundation of asthma treatment, many individuals with severe asthma rely on systemic glucocorticoids for asthma management. For asthma management and exacerbation prevention, newer monoclonal antibodies are offering an alternative to systemic glucocorticoids. Omalizumab, the first monoclonal antibody medication licensed for the treatment of asthma, targeted IgE, a component of the allergic cascade. Two monoclonal antibodies have recently been authorized as an add-on treatment for poorly controlled eosinophilic asthma. These are directed towards interleukin-5, a cytokine that is important in fostering eosinophil differentiation, survival, and recruitment. Another antibody that targets the interleukin-5 receptor on eosinophils is nearing approval. Other monoclonal antibodies are being developed to target a wide range of mediators in the inflammatory cascade.
The evaluation of previously authorized monoclonal antibodies that may be useful in the treatment of asthma is still continuing. Understanding the biology of asthma and airway hyperreactivity, as well as the use of biomarkers, may enable doctors to focus monoclonal antibody treatment on individuals who are most likely to respond to these novel medications.