Distribution of biomarkers in severe asthma and severe uncontrolled asthma

Introduction: Asthma is a heterogeneous condition and treatment response may vary. Understanding the distribution of biomarkers in patients with severe asthma despite treatment may help inform treatment decisions. Aim: To characterise the distribution of biomarkers in severe asthma. Methods: NOVELTY (NCT02760329) is a global, observational study of patients with physician-assigned asthma and/or COPD. This analysis included patients who at baseline had severe asthma or severe uncontrolled asthma and had biomarker and allergy history data. Asthma severity was physician-assessed, with uncontrolled asthma defined as an Asthma Control Test (ACT) score <20 or ≥1 exacerbation in the past 12 months. This analysis included history of allergy, high blood eosinophil (EOS) count (≥300 cells/µL) and high fractional exhaled nitric oxide (FeNO; ≥25 ppb). Results: Overall, 652 patients had physician-assessed severe asthma at baseline, and 480 (74%) of these met the criteria for severe uncontrolled asthma. Distribution of the 2 biomarkers and history of allergy were similar between these groups (figure). In both groups, 11.5% of patients were positive for all 3 variables (high EOS, high FeNO, history of allergy), and 13.3% of patients for none. Conclusion: The distribution and overlap of high EOS, high FeNO and history of allergy were similar among NOVELTY patients with severe asthma and the subset of these with severe uncontrolled asthma.