Concurrent Blood Eosinophils and FeNO as Biological Therapy Indicators in Severe Asthma: Findings From the Precision Medicine Intervention in Severe Asthma Study

초록

Background: The combination of pretreatment peripheral blood eosinophil count (BEC) and FeNO levels for optimizing the therapeutic response of T2-biologics in patients with severe eosinophilic asthma (SEA) remains unclear. Objective: To compare longitudinal clinical outcome changes across subgroups stratified by the combination of high and low levels of BEC and FeNO. Methods: Overall, 278 patients with SEA (anti-IL-5/IL-5Rα users: n = 82; and anti-IL-4Rα users: n = 196) were stratified based on pretreatment BEC and FeNO levels and observed for 6 to 12 months. Group differences in exacerbation rate, lung function, Asthma Control Test, BEC, FeNO, and clinical remission over time were compared. Results: Approximately 75% and 63% of patients presented with concurrent high BEC (≥300 cells/μL) and high FeNO (≥25 ppb) in the anti-IL-5/IL-5Rα and anti-IL-4Rα groups, respectively. Among anti-IL-5/IL-5Rα users, we observed no significant differences among BEC-FeNO groups regarding exacerbation rates or clinical remission. Patients with concurrent high BEC and FeNO levels demonstrated more pronounced reductions in both markers and greater FEV<inf>1</inf> and Asthma Control Test score improvements compared with those with high FeNO but low BEC. In the anti-IL-4Rα group, patients with low BEC and FeNO, and those with high BEC but low FeNO, exhibited a significantly lower likelihood of achieving clinical remission (odds ratio [95% CI]: 0.08 [0.00-0.46] and 0.11 [0.01-0.63], respectively) and a slower rate of FEV<inf>1</inf> improvement (all P for slope < .05) compared with those with concurrent high BEC and FeNO. Conclusion: Concurrently elevated BEC and FeNO levels ensure optimal therapeutic response in patients with SEA who are treated with T2 biologics. © 2025 American Academy of Allergy, Asthma & Immunology

키워드