A Retrospective Claims Database Study to Clarify Disease Burden of Severe Asthma Patients with Type 2 High or Low Inflammation

Abstract

Norihiro Harada,1 Naoyuki Makita,2 Kenya Fukui,2 Kenichiro Nishida,2 Kaori Oneda,2 Naoki Tashiro2 1Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan; 2AstraZeneca K.K., Osaka, JapanCorrespondence: Norihiro Harada, Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-Ku, Tokyo, 113-8431, Japan, Tel [phone], Fax [phone], Email [email protected]: The disease burden of severe asthma patients stratified by type 2 (T2) biomarkers is not well studied in large patient samples, especially for T2-low severe asthma patients. Using a Japanese medical record database, we investigated disease and economic burdens in T2-high and T2-low severe asthma patients.Patients and Methods: Data of severe asthma patients (receiving high-dose inhaled corticosteroids and additional asthma-related controller medications or oral corticosteroids [OCS] prescription [≥ 183 days] during the 1-year baseline period) were analyzed in the Real World Data database, comprising electronic medical records from Japanese medical institutions. Severe asthma patients were stratified into a T2-high population with higher eosinophils (≥ 150 cells/μL) and/or higher total immunoglobulin E (IgE, ≥ 75 IU/mL) or a T2-low population with lower eosinophils (< 150 cells/μL) and lower total IgE (< 75 IU/mL). The incidence of asthma exacerbation events and drug costs were analyzed for each population. Different T2 thresholds were explored, including eosinophil count 300 cells/μL and/or IgE 150 IU/mL.Results: Of the 732 severe asthma patients, 599 (81.8%) patients had T2-high type, and 133 (18.2%) had T2-low type. Proportions of the T2-high patients (30.6%) with asthma exacerbations, defined as a composite outcome, including OCS burst, injectable steroid use, and hospitalization, were similar to those of T2-low type (34.6%). The annual drug cost was similar between T2-high (175,487 JPY) and T2-low (165,322 JPY) populations.Conclusion: In this large-scale study, both T2-high and T2-low severe asthma patients in Japan were shown to have a high disease burden and high economic burden, suggesting an unmet treatment need.Keywords: phenotype, disease exacerbation, treatment, Japan

Keywords

• phenotype
• disease exacerbation
• treatment
• japan