Mepolizumab May Be Protective Against Small Airway Disfunction Exacerbation Risks in Children

Airway resistance was associated with increased exacerbation rates in the placebo group but not the mepolizumab treatment groups

MILWAUKEE, Feb. 17, 2026 /PRNewswire/ -- Mepolizumab-treated groups of children experience lower risk of airway dysfunction compared to placebo groups, according to new research being presented at the 2026 AAAAI Annual Meeting.

The researchers suggest that mepolizumab may produce a potential protective effect of anti-IL5 therapy in children with small airway dysfunction, highlighting an important treatment option to optimize patient care.

"In a secondary analysis of a pediatric randomized controlled trial, we assessed the association between baseline lung function impairment (measured by spirometry and impulse oscillometry) and exacerbation risk. Greater baseline obstruction was associated with higher exacerbation frequency in both placebo and mepolizumab treatment groups. Whereas greater baseline airway resistance was associated with higher exacerbation frequency mainly in the placebo group, indicating a potential protective effect of anti-IL5 therapy in children with small airway dysfunction," said co-author Courtney Gaberino, MD.

Within the study, 271 participants, aged 6-17 years old, with exacerbation-prone asthma and blood eosinophils >=150/microliter, were randomized to receive placebo or mepolizumab injections added to their guideline-based care for 52 weeks. Researchers collected spirometry (GLI race-neutral values) and impulse oscillometry (IOS) data and examined the association between baseline lung function and the number of exacerbations during the trial by using negative binomial regression models.

The researchers found that greater baseline airway resistance at 5Hz (R5), 5Hz-20Hz (R5-20) and the area under the curve of reactance (AX) were all associated with increased exacerbation risks for the children treated with a placebo. However, airway dysfunction as assessed by IOS was not associated with an exacerbation risk in the group of mepolizumab-treated children. In a combined model, researchers found no significant interaction between treatment group and IOS parameters in predicting the exacerbation risk (R5, R5-20, AX). Lower FEV1/FVC at the baseline was significantly associated with greater exacerbation frequency for both the placebo and mepolizumab-treatment groups of children.

Visit aaaai.org to learn more about biologics. Research presented at the 2026 AAAAI Annual Meeting, February 27 – March 2 in Philadelphia, PA, is published in an online supplement to The Journal of Allergy and Clinical Immunology (JACI).

The American Academy of Allergy, Asthma & Immunology (AAAAI) is the leading membership organization of more than 7,100 allergists, asthma specialists, clinical immunologists and other professionals with a special interest in the research and treatment of allergic and immunologic diseases. Established in 1943, the AAAAI is the go-to resource for patients living with allergies, asthma and immune deficiency disorders.

SOURCE American Academy of Allergy, Asthma & Immunology (AAAAI)