The North-Western Italian experience with anti IL-5 therapy amd comparison with regulatory trials

Background: The severe forms of asthma represent a major burden, because of severity of symptoms, costs and impact on everyday life. Recently, Mepolizumab (MEP) was approved and marketed for the treatment of hypereosinophilic severe asthma. This anti-IL-5 monoclonal antibody reduced exacerbation rates and oral corticosteroid (OCS) use in well selected patients. The aim of this study was to evaluate the characteristics of patients receiving MEP in a real-life setting. Thus, we describe a retrospective analysis of patients treated with MEP in six centres in North Western Italy, including those who participated in the main regulatory trials. Methods: The baseline data, before prescription, from six North Western Italy severe asthma clinics, between June 1st 2017 and December 31st 2017, were evaluated. The collected real-life data were then compared with those of SIRUS, MENSA, DREAM and MUSCA trials. Results: Sixty-five patients were included (45% female; mean age 56 years; age range 19-84). Main observed differences with regulatory trials could be observed in eosinophils blood count at baseline, where the mean of our real-life patients (653 cells/μL) was overall higher than the one of all trials (240 cells/μL, 296 cells/μL, 253 cells/μL; p < 0.0001). The incidence of polyposis was also significantly higher in our sample (72% vs. 24%, 49%, 10%, 19%; p < 0.0001). The daily average dose of OCS was lower in our real-life patients (9 mg), if compared with SIRIUS (13.7 mg), MENSA (13.2) and MUSCA (13), and similar to the data published in DREAM (10.8). Conclusions: The comparison of real-life patients' characteristics with regulatory trials, displayed several apparent discrepancies. The demographic and clinical aspects were similar in all groups, whereas other features (eosinophil count, pulmonary function FEV1%) differed. These data, for the first time, could represent a basis for a more accurate prescription of the drug.