Evolution of Disease Burden in Severe Asthma Patients by Biological Treatment Status: Interim Analysis of the BREATHE Study.

Purpose: The objective of this work was to describe the disease characteristics and evolution over time among severe asthma patients in Spain, with and without biologic treatment, based on the interim analysis of the BREATHE study. Methods: The BREATHE study is a multicentre, observational, longitudinal cohort study conducted in Spain, involving patients aged ≥12 years with severe asthma, who were treated with high doses of ICS + LABA for at least 6 months prior to inclusion. This interim analysis was carried out with the information from the baseline and retrospective visits (at 6 and 12 months prior to index date) collected on June 29, 2023, including sociodemographic, clinical characteristics, lung function, symptoms, laboratory assessments, and treatment regimens. Results: The interim analysis of the BREATHE study included 344 patients, with 325 meeting all criteria for analysis. The study found that 50.8% of patients had partially or poorly controlled asthma according to the ACT score, with a higher percentage of well-controlled asthma in patients undergoing biological therapy (52.5%) compared to those without (45.0%). Despite biological treatment, patients continued to experience exacerbations, and the most common treatments at the index date were ICS/LABA, biological therapy, and antileukotrienes. Conclusion: The interim analysis of the BREATHE study reveals that severe asthma patients in Spain, predominantly female and around 50 years old, continue to experience exacerbations despite biological therapy, with nearly half having poorly controlled asthma. The study highlights the need to reassess treatment strategies for patients with high biomarker levels and frequent exacerbations.