The following is the summary of “Overall Response to Anti-IL-5/Anti-IL5-Rα Treatment in Severe Asthma Does Not Depend on Initial Bronchodilator Responsiveness” published in the December 2022 issue of Allergy and Clinical Immunology by Mümmler, et al.

Licensing trials with anti-interleukin 5/anti-interleukin 5 receptor alpha (anti-IL-5/anti-IL-5Rα) biologics in severe asthma have included patients who showed positive bronchodilator responsiveness (BDR; change in forced expiratory volume in 1 second  [ΔFEV1] ≥  +200 mL and ≥+12%). Patients with severe, uncontrolled asthma often have a negative BDR in clinical practice, though. The purpose of this study is to determine if individuals with a positive or negative BDR at baseline have a different response to anti-IL5/anti-IL5Rα treatments.

Anti-IL-5/anti-IL-5Rα therapy results in patients with severe asthma, stratified by baseline BDR, retrospective multicenter investigation. There were 133 total patients, 37 of whom had a positive BDR at baseline and 96 who did not. No significant difference was found between patients with positive and negative BDR (ΔFEV1 +493 mL vs +306 mL; P=.06) after therapy with anti-IL-5/anti-IL-5Rα compared with baseline (P< .0001). Positive BDR was associated with an increase in forced vital capacity (FVC; ΔFVC: +85 mL versus +650 mL; P<.01) and a decrease in residual volume (RV; ΔRV: +113 mL vs -307 mL; P<.01). Reduction in the rate of exacerbations (exacerbations 0 vs -2; P=.07), usage of oral corticosteroids (OCS) (patients on OCS -35% vs -39%; P=.99), and improvement in the Asthma Control Test (ΔACT) score (ACT 6 vs 5; P=.7) were also comparable between the 2 groups.

Response parameters were not significantly correlated with whether the BDR was positive or negative in a multivariate logistic regression analysis. Both groups responded favorably to treatment, with improvements in OCS use, exacerbations, and symptom control. During anti-IL-5/anti-IL-5Rα treatment, pulmonary function improved in both groups, however, there were notable disparities in response patterns.