MESOS: considerations in designing a mechanistic study for a biologic used to treat asthma

Eosinophils are key effector cells in asthma-associated airway inflammation and remodeling; IL-13 is involved in regulating eosinophil activity. Tralokinumab, currently in Phase III clinical development for patients with severe uncontrolled asthma, is an investigational fully human monoclonal antibody designed to inhibit IL-13. In Phase II studies, tralokinumab improved lung function and had other clinical benefits in those patients with asthma who had an upregulated IL-13 axis. In a subgroup of patients that underwent quantitative computed tomography, there were improvements in airway morphometry, suggestive of a possible effect upon remodeling. The Phase II MESOS study (NCT02449473) aims to better understand the mechanism of action of tralokinumab in improving asthma control, by investigating tralokinumab effects on eosinophil-driven inflammation and airway remodeling.