Impact of benralizumab on airway structure/function in severe eosinophilic asthma

The BURAN study (ClinicalTrials.gov: NCT05552508) was a multicenter open-label study evaluating airway structure/function changes in adults with severe eosinophilic asthma (SEA) following eosinophil depletion by benralizumab. We assessed the changes in airway structure/function following treatment with benralizumab in adults with SEA. We recruited adults (18–70 years) with SEA inadequately controlled with inhaled corticosteroids plus long-acting β2-agonists. Patients received subcutaneous benralizumab 30 mg every 4 weeks (three doses total). Computed tomography scans of the lungs were analyzed using Functional Respiratory Imaging (FRI). The primary endpoint was change from baseline to Week 13 in total mucus volume at total lung capacity. Secondary endpoints included change from baseline to Week 13 in mucus plug score and airway structure/function, and correlations between change in FRI endpoints and spirometry assessments (forced expiratory volume in 1 s [FEV 1 ] and forced vital capacity [FVC]). The primary analysis set included 39 patients (mean [standard deviation] age, 54.5 [11.4] years; 59.0% female, 92.3% White). Total mucus volume from baseline to Week 13 was significantly reduced (Δ − 0.13 mL; P = .033), with more pronounced reduction in those with ≥ 4 mucus plugs at baseline (∆ −0.18; P = .036). Similarly, mucus plug scores were significantly reduced (Δ − 11.0; P = .042). Mucus burden reduction was accompanied by lung function improvement. No significant changes from baseline were observed in air trapping, airway wall volume, specific airway volume, and lung volume. At Week 13, changes in total mucus volume ( r = − .501; P < .001) and total mucus plug scores ( r = − .600; P < .001) were correlated with improvements in pre-bronchodilator FEV 1 and FVC. Mucus burden was significantly reduced following treatment with benralizumab in patients with SEA. ClinicalTrials.gov ID: NCT05552508 (registration date: 23 September 2022).