Breath Test Predicts Biologic Response in Severe Asthma

Severe eosinophilic asthma can now be treated with biologic therapies that reduce attack frequency and, in some cases, allow reductions in corticosteroid doses. Yet response rates vary, and clinicians have struggled to predict which patients will benefit before initiating treatment. A new study from researchers at the University of Liège and Liège University Hospital proposes a simple breath‑sample test to guide therapy selection early in the treatment course.

The investigators, whose findings appear in the American Journal of Respiratory and Critical Care Medicine, analyzed volatile organic compounds in exhaled air to identify biomarkers that correlate with therapeutic response. By measuring these compounds before starting biologics, the test could help clinicians choose the most appropriate drug and avoid ineffective treatments, potentially improving outcomes and reducing unnecessary medication exposure.

If validated in larger trials, this breath‑based approach could become a routine, non‑invasive tool for personalizing biologic therapy in severe eosinophilic asthma, offering a clearer pathway to effective, individualized care.