Influence of newly initiated biologic therapy on the dose of ICS therapy - Data from the German Asthma Net.

BACKGROUND: Real-world data on inhaled corticosteroid (ICS) reduction after biologic initiation in severe asthma are limited. OBJECTIVES: We assessed high dose (HD)-ICS reduction and its association with asthma control, exacerbations, lung function, and fractional exhaled nitric oxide (FeNO). METHODS: Adults in the German Asthma Net registry initiating benralizumab, dupilumab, mepolizumab, omalizumab, reslizumab, or tezepelumab with documented ICS use and 4-month, 1-, or 2-year follow-up were analyzed. ICS doses were converted to beclomethasone dipropionate equivalents (BDE) per GINA and reducers were defined by HD-ICS step-down to medium/low-dose ICS during follow-up and compared to non-reducers. Remission was defined as an Asthma Control Test (ACT) ≥20, no exacerbations, and no oral corticosteroids after 1 year of biologics. Analyses used adjusted linear, log-linear, and Poisson regression models (standard or mixed-effects, as appropriate), along with Kendall's τ and Spearman's rank correlation coefficients. RESULTS: Among 1,181 patients (1,372 visits; 55 ± 13 years; 57% female), HD-ICS use declined from 90.7% to 79.9% over 2 years. Median BDEs dose decreased from 1600 to 1000 μg (n=287; P=.004). ICS-Reduction was observed in patients with greater improvements in ACT, ACQ-5 and mAQLQ than in patients not reducing (all P<.05) without worsening exacerbations over 2 years. Reduction after 4 months was associated with better FEV1 improvement (all P=.03) but not thereafter; other lung function measures improved comparably, except for greater FRC reduction among reducers at year 2 (P=.02). FeNO decreased overall, with a smaller 1-year reduction among reducers (P = .050). Remission was associated with higher ICS reduction rates (year 1: 23.0% vs. 8.7 %, P=.0001; year 2: 26.3% vs. 10.8%, P=.004). Correlation analyses largely confirmed the main findings. CONCLUSION: ICS reduction was associated with improved patient-reported outcomes without worsening exacerbations, lung function or FeNO.