Biologic treatment options for severe asthma.

Asthma is a common condition that causes episodic expiratory airflow limitation due to bronchial smooth muscle constriction and airways inflammation resulting in increased respiratory symptoms and acute asthma exacerbations. Patients with severe asthma have relied on either recurrent courses or daily use of oral corticosteroids (OCS) to control their disease. However a high level of OCS exposure is associated with significant morbidity and mortality. In recent years the elucidation of the role of T2 inflammation underpinning asthma pathogenesis has led to the development of monoclonal antibody (mAb) therapies targeting this pathway. Established therapies now include omalizumab targeting IgE, mepolizumab and reslizumab targeting IL-5, benralizumab targeting the IL-5R and dupilumab targeting IL-4R. For many patients these therapies have been transformative and their use has additionally advanced our understanding of the immunology that underpins the disease. This article reviews the biologic therapies currently available for the treatment of severe asthma.