Lung function trajectories in a cohort of patients with moderate‐to‐severe asthma on mepolizumab, omalizumab, or dupilumab

Abstract Background Lung function is an independent predictor of mortality. We evaluated the lung function trajectories of a cohort of patients with asthma receiving biologic therapy. Methods We identified 229 monoclonal antibody‐naïve adult patients with moderate‐to‐severe asthma who initiated omalizumab, mepolizumab, or dupilumab between 2010 and 2022 in a large healthcare system in Boston, MA. Generalized additive mixed models were used to estimate the lung function trajectories during the 156 weeks following biologic initiation. Response was defined as an improvement in FEV 1 or a decrease of ≤0.5% per year. The Kaplan–Meier estimator was used to assess time to no additional improvement in FEV 1 in responders. All models were adjusted for age, sex, body mass index, smoking status, baseline exacerbation rate, and baseline blood eosinophil count. Results Eighty‐eight patients initiated mepolizumab, 76 omalizumab, and 65 dupilumab. Baseline eosinophil count was highest in the mepolizumab group (405 cells/mcL) and lowest for omalizumab (250 cells/mcL). Both FEV 1 and FVC improved in the mepolizumab group (FEV 1 + 20 mL/year; FVC +43 mL/year). For omalizumab, there was an initial improvement in the first year followed by decline with an overall FEV 1 loss of −44 mL/year and FVC −32 mL/year. For dupilumab, both FEV 1 (+61 mL/year) and FVC (+74 mL/year) improved over time. Fifty percent of the mepolizumab group, 58% omalizumab, and 72% of dupilumab were responders. The median time to no additional FEV 1 improvement in responders was 24 weeks for omalizumab, 48 weeks for mepolizumab, and 57 weeks for dupilumab. Conclusion In this clinical cohort, mepolizumab, omalizumab, and dupilumab had beneficial effects on FEV 1 and FVC with distinct post‐initiation trajectories.