Effect of omalizumab on lung function and eosinophil levels in adolescents with moderate-to-severe allergic asthma

Background: Omalizumab improves clinical outcomes in patients with asthma. Several studies have shown lung function improvements with omalizumab; however, this has not been examined exclusively in adolescents. Objective: To assess the effect of omalizumab on lung function and eosinophil counts in adolescents with uncontrolled moderate-to-severe allergic asthma. Methods: In this post hoc analysis, data from adolescents aged 12 to 17 years from 8 randomized trials of omalizumab were pooled (studies 008, 009, and 011, and SOLAR, INNOVATE, ALTO, ETOPA, and EXTRA). Changes from baseline to end of study in forced expiratory volume in 1 second (FEV1), percent predicted FEV1 (ppFEV(1)), forced vital capacity (FVC), and blood eosinophil counts were assessed by fitting an analysis of covariance model and calculating least squares mean (LSM) difference for omalizumab vs placebo. Results: A total of 340 adolescents were identified (omalizumab, n = 203 [59.7%]; placebo, n = 137 [40.3%]). Omalizumab increased all baseline lung function variables more than placebo by end of study: LSM treatment differences (95% confidence interval) were 3.0% (0.2%-5.7%; P = .035), 120.9 mL (30.6- 211.2 mL; P = .009), and 101.5 mL (8.3-194.6 mL; P = .033) for ppFEV(1), absolute FEV1, and FVC, respectively. The LSM difference demonstrated a greater reduction in eosinophil counts for omalizumab vs placebo: -85.9 cells/mu L (-137.1 to -34.6 cells/mu L; P = .001). Conclusion: Omalizumab was associated with lung function improvements and circulating eosinophil counts reductions in adolescents with moderate-to-severe uncontrolled asthma. Findings emphasize the effect of omalizumab in young patients and the need to optimize treatment early in the disease course. (C) 2019 American College of Allergy, Asthma & Immunology.