Efficacy predictors of omalizumab in Chinese patients with moderate-to-severe allergic asthma: Findings from a post-hoc analysis of a randomised phase III study

Jing Li,Changzheng Wang,Chuntao Liu,Jian Kang,Lingfei Kong,Yijiang Huang,Shuang Liu,Mao Huang,Lu Wang,Robert Fogel,Xavier Jaumont,Jing Yang,Nanshan Zhong

doi:10.1016/j.waojou.2020.100469

Abstract

BackgroundOmalizumab has demonstrated efficacy as an add-on therapy in Chinese patients with moderate-to-severe allergic asthma. This post-hoc analysis assessed the potential predictors for the efficacy of omalizumab in these patients. MethodsA post-hoc analysis was performed on a Phase III, randomised, controlled study conducted in Chinese patients with moderate-to-severe persistent allergic asthma (NCT01202903). We evaluated if levels of pre-treatment serum total immunoglobulin-E (IgE) and blood eosinophil (EOS), asthma severity, allergen profile, history of perennial allergic rhinitis (PAR), and free IgE level during omalizumab treatment were predictive of omalizumab's efficacy. ResultsThis analysis included 608 patients (omalizumab, N = 306; placebo, N = 302). Improvements in forced expiratory volume in 1 s (FEV1), standardized Asthma Quality of Life Questionnaire (AQLQ), Asthma Control Questionnaire (ACQ), and Global Evaluation of Treatment Effectiveness (GETE) scores with omalizumab treatment compared with placebo were observed in patients with baseline IgE levels ≥76 IU/mL (irrespective of the EOS count). Relatively greater improvements with omalizumab treatment was also noted in patients with both moderate or severe allergic asthma (regardless of asthma severity), and patients sensitised to >3 allergens and with a history of PAR. All patients who were treated with omalizumab achieved free IgE levels below 50 ng/mL by Week 1. Similar clinical outcomes were observed in the subset of patients who achieved free IgE levels of <25 and ≥ 25 ng/mL. ConclusionsIn Chinese patients with moderate-to-severe allergic asthma, baseline IgE and allergen profile (number/PAR history) are potential predictors of treatment response to omalizumab. Trial registrationNCT01202903 (www.clinicaltrials.gov).

Highlights

The prevalence of asthma has increased in China over the past several decades.[1,2] The overall prevalence of asthma in China is estimated at 4.2% in the population aged !20 years, representing 45.7 million Chinese adults.[3]
The mean total IgE, EOS level, baseline Asthma Quality of Life Questionnaire (AQLQ) score, Asthma Control Questionnaire (ACQ) score, forced expiratory volume in 1 s (FEV1)% predicted mean values were balanced between patients randomised to the omalizumab and placebo arms (Table 1); for the PK/PD population, the baseline total/free IgE levels were similar in both treatment arms in the PK/PD population (Table 1)
Serum total IgE level and blood eosinophil count as a predictor of treatment outcome Dividing the full analysis set (FAS) population into 4 subgroups based on baseline serum total IgE level and blood EOS count, most patients were stratified to Group 1 and Group 3

Summary

Introduction

The prevalence of asthma has increased in China over the past several decades.[1,2] The overall prevalence of asthma in China is estimated at 4.2% in the population aged !20 years, representing 45.7 million Chinese adults.[3] Of those, approximately 6.0% and 30.3% of asthmatic patients in China were categorized as having severe[4] and moderate[5] asthma, respectively. Asthma is a heterogeneous disease with several phenotypes, including allergic asthma and eosinophilic asthma.[6] More than 50% of asthmatic patients in China are sensitised to allergen(s), with house dust mites being the most prevalent.[7]. Omalizumab has demonstrated efficacy as an add-on therapy in Chinese patients with moderate-to-severe allergic asthma. This post-hoc analysis assessed the potential predictors for the efficacy of omalizumab in these patients

Methods

Results

Conclusion