GSK plc's Nucala (mepolizumab) has been approved by the US FDA as an add-on treatment for adults with chronic obstructive pulmonary disease (COPD) who have an eosinophilic phenotype, based on successful phase III trials completed prior to May 22, 2025, showing nearly 70% of inadequately controlled COPD patients could benefit. This represents a significant treatment option for over a million patients at risk of exacerbations.