Asthma affects over 25 million Americans and is one of the most common chronic diseases of childhood and adulthood. It is driven by airway inflammation — predominantly eosinophilic — causing bronchial hyperresponsiveness and reversible airflow obstruction. Asthma severity ranges from mild intermittent to severe persistent, with management stepped up or down according to symptom control. The cornerstone of asthma treatment is inhaled corticosteroid (ICS) therapy, which reduces airway inflammation, prevents exacerbations, and is the most important controller medication. Short-acting beta-agonists (SABA) remain the standard rescue medication for acute symptoms. Biologic therapies targeting IL-5, IL-4/13, TSLP, and IgE have transformed the management of severe uncontrolled eosinophilic asthma, reducing exacerbations by 50–70% in this population.
