Comparison of the influence of omalizumab and mepolizumab on airway remodeling in severe asthma patients with evaluation of detection techniques: endobronchial ultrasound (EBUS) and high-resolution computed tomography (HRCT)

Abstract

<b>Background:</b> Severe asthma involves chronic inflammatory process in the airways leading to changes in airway structure known as airway remodeling. Biological treatment with anti-IgE (omalizumab) or anti-IL5 (mepolizumab) can potentially limit this process. <b>Aims and objectives:</b> To assess the impact of biological treatment with omalizumab and mepolizumab on airway remodeling in severe asthma and to compare efficacy of its evaluation by chest HRCT and EBUS. <b>Methods:</b> In 15 severe eosinophilic asthma patients and in 12 severe allergic asthma patients HRCT and EBUS were performed before and after 1 year of biological treatment. The 10th right segment bronchus was chosen for HRCT analysis with measurement of percentage of wall area (WA%) and ratio between luminal area and total area (Ai/Ao). In EBUS mean thickness of bronchial wall and its inner layers (L1, L2, L3) were evaluated. <b>Results:</b> In EBUS, significant reduction in mean bronchial wall thickness was observed both in omalizumab (1.34±0.04mm vs 1.25±0.04mm, p&lt;0.001) and mepolizumab (1.3±0.08mm vs 1.26±0.07mm, p&lt;0.001) treatment group. In HRCT, changes in WA% and Ai/Ao were not significant both in omalizumab (WA%: 56.59±6.39 vs 57.49±5.72 [p=0.61], Ai/Ao: 0.43±0.06 vs 0.42±0.005 [p=0.79]) and mepolizumab (WA%: 67.9±6.61 vs 64.85±7.1 [p=0.16], Ai/Ao: 0.32±0.07 vs 0.35±0.07 [p=0.17]) treatment group. <b>Conclusions:</b> One year of treatment with omalizumab and mepolizumab resulted in comparable improvement of airway remodelling parameters. The changes were detected in invasive EBUS but not in non-invasive HRCT.