González Barcala, Francisco JavierBobolea, IrinaDomínguez-Ortega, JavierBañas-Conejero, DavidAntelo-Cea, EstebanMartínez-Moragón, EvaCarrillo-Díaz, TeresaBlanco-Aparicio, MarinaDomingo, Christian2026-02-062026-02-062025González-Barcala, F.-J., Bobolea, I., Domínguez-Ortega, J., Bañas-Conejero, D., Antelo-Cea, E., Martínez-Moragón, E., Carrillo-Díaz, T., Blanco-Aparicio, M., & Domingo, C. (2025). Time is lung: higher preservation of lung function in severe asthma patients after earlier mepolizumab treatment. ERJ Open Research, 11(1). https://doi.org/10.1183/23120541.00211-20242312-0541https://hdl.handle.net/10347/45710Introduction Severe asthma involves a persistent inflammation of the airways that is associated with a greater risk of exacerbations. Exacerbations are associated with a higher lung function decline over time. The prevention of lung function decline could become a strategy for disease modification, and this could be more likely to happen in patients with an earlier therapeutic approach. Thus, this study means to analyse the effect of asthma duration in clinical outcomes such as lung function in patients from the REDES study. REDES was an observational real-world study that assessed the effectiveness and safety of mepolizumab 100 mg s.c. every 4 weeks for 12 months in 318 patients with severe asthma in Spain. Methods This post hoc analysis evaluated how disease duration affected the study results through a stratification according to quartiles on their disease progression. Continuous analyses were also performed to assess the impact of confounder variables on forced expiratory volume in 1 s (FEV1) (%). Results At baseline, patients with shorter time of disease had a significantly higher lung function than patients with longer asthma duration. At 12 months, pre-bronchodilator (BD) FEV1 values and the proportion of patients with (Formula Presented)80% pre-BD FEV1 were higher according to a shorter disease persistence (Q1>Q2>Q3>Q4). Conclusion These results support that time of disease persistence contributes to the lung function decline of patients with severe asthma, uncontrolled while on previous treatment, and that an earlier approach with mepolizumab may imply a higher preservation of their lung function.engCopyright ©The authors 2025 This version is distributed under the terms of the Creative Commons Attribution Licence 4.0.Attribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article2025-12-1210.1183/23120541.00211-2024open access2312-0541