Mepolizumab for severe eosinophilic asthma-real-life data

ABSTRACT

Background: Mepolizumab, a humanized monoclonal antibody against IL-5, is a therapeutic option in patients with severe eosinophilic asthma. Its efficacy has been shown in clinical trials. Our aim is to present data from our center to corroborate this evidence in the complexity of real-life patients. Method: A retrospective study of patients with severe eosinophilic asthma treated with mepolizumab in our center was performed. We collected data regarding demographics, eosinophilic blood count, FEV 1 , fractional exhaled nitric oxide (FeNO), clinically significant exacerbations [need to start or increase oral corticosteroids (OCS), emergency department visit and/or hospitalization], OCS and safety profile, before and after patients started mepolizumab. Results: A total of 12 patients were included (9 female, mean age 53.7 ± 8.9 years old);10 patients had concomitant chronic rhinosinusitis with nasal polyps. Mepolizumab was administered in a dose of 100 mg every 4 weeks, except for 2 patients diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA) (300 mg every 4 weeks). The mean duration of treatment was 13.75 months [3 - 28 months]. Due to COVID-19 pandemics restriction it was not possible to assess absolute eosinophilic count in 2 patients, as well as FeNO and FEV 1 in 2 different patients after treatment. The mean value before and after treatment for each outcome were the following absolute eosinophilic blood count, from 537.5/μl to 116/μl ( p = 0.005);FEV 1 , from 1.44L to 1.84L ( p = 0.036);FeNO, from 62.27ppm to 41.8ppm ( p = 0.260);clinically significant exacerbations, from 2.83 in the previous year to 0.25 ( p = 0.007). Prior to treatment, 8 patients were treated with daily OCS, and after starting mepolizumab 3 of them were able to stop OCS and the others reduced daily dose (mean dose reduction 64.7%, ranging from 25% to 98.5%). The only side effect reported was sporadic headache, and no one discontinued treatment. Conclusion: In our sample, we observed a significant reduction in eosinophilic blood count, clinically significant exacerbations and OCS use, as well as improvements in FEV 1 , in patients with severe eosinophilic asthma treated with mepolizumab, with a good safety profile. This information supports data from clinical trials and early real-life experience in other populations.