Characteristics and Disease Burden of Patients With Eosinophilic Granulomatosis With Polyangiitis Initiating Mepolizumab in the United States

Abstract

Background/Objective Although the high disease burden associated with eosinophilic granulomatosis with polyangiitis (EGPA) has been established, the disease burden in patients initiating mepolizumab in real-world practice is poorly understood. This study aimed to assess characteristics and burden of real-world patients with EGPA initiating mepolizumab. Methods This was a database study (GSK study ID: 214156) of US patients (≥12 years old) with EGPA and ≥1 mepolizumab claim (index date) identified from the Merative MarketScan Commercial and Medicare Supplemental Databases (November 1, 2015, to March 31, 2020). Outcomes assessed in the 12-month baseline period before index (inclusive) included patient characteristics, treatment use, EGPA relapses, asthma exacerbations, health care resource utilization, and costs. Results In the 103 patients included (mean age, 51.1 years; 63.1% female), the most common manifestations were asthma (89.3%), chronic sinusitis (57.3%), and allergic rhinitis (43.7%). In total, 91.3% of patients had ≥1 oral corticosteroid (OCS) claim (median dose, 7.4 mg/d prednisone-equivalent), 45.6% were chronic OCS users (≥10 mg/d during the 90 days preindex), 99.0% had ≥1 EGPA-related relapse, and 62.1% ≥1 asthma exacerbation. During the baseline period, 26.2% and 97.1% of patients had EGPA-related inpatient admissions and office visits, respectively. Median all-cause total health care costs per patient were $33,298, with total outpatient costs ($16,452) representing the largest driver. Conclusions Before initiating mepolizumab, a substantial real-world EGPA disease burden is evident for patients, with resulting impact on health care systems, and indicative of unmet medical needs. Mepolizumab treatment, with a demonstrated positive clinical benefit-risk profile may represent a useful treatment option for reducing EGPA disease burden.