Real-world effectiveness of omalizumab in allergic asthma patients with low or high blood eosinophils: A retrospective claims analysis study

Introduction: Allergic asthma and eosinophilic asthma are common phenotypes of severe asthma. However, these two phenotypes are not mutually exclusive. Biologics targeting interleukin (IL)-5 are only indicated in patients with high blood eosinophil (EOS) counts. Omalizumab is indicated in patients with allergic asthma. We conducted this study to determine whether baseline blood EOS counts determine response to omalizumab in patients with severe allergic asthma (SAA) in the real-world setting. Methods: Using Optum’s ClinformaticsTM Data Mart (CDM), a U.S. administrative claims database of a large, commercially insured population, we performed a claims analysis of patients with severe asthma receiving omalizumab from 2008 to 2016. We examined the annualiaed exacerbation rate of SAA patients who were treated with omalizumab for at least 6 months, compared to a 12 month pre-treatment period, in two sub-groups of patients whose blood EOS count was either Results: We identified 424 omalizumab-treated pediatric and adult patients who had a measured blood EOS count; 179 patients had an EOS count ≥300 cells/µL and 245 patients Conclusion: Our data demonstrate that omalizumab is effective in reducing exacerbations in SAA patients with high and low blood EOS counts.