NUCALA, generically known as mepolizumab, is a prescription medication designed for the treatment of severe eosinophilic asthma in patients aged 6 years and older, chronic rhinosinusitis with nasal polyps in adults, and hypereosinophilic syndrome (HES) in adults and children aged 12 years and older. It is a type of biologic therapy, specifically an interleukin-5 antagonist monoclonal antibody, that works by targeting and reducing the levels of eosinophils, a type of white blood cell that plays a significant role in the inflammation and exacerbations associated with these conditions. NUCALA is administered through a subcutaneous injection and is intended for use under the guidance of healthcare professionals, offering a targeted approach to managing symptoms and improving the quality of life for patients with these eosinophil-driven diseases.