Severe Asthma Exacerbations and Mepolizumab Treatment

The patients will treated with subcutaneous Mepolizumab at 100 mg every 30 days. Patients will be recruited among those eligible to Mepolizumab treatment according to the Italian Medicine Agency (AIFA; Agenzia Italiana del Farmaco) guidelines who will accept to participate to the study. In particular inclusion criteria will be: severe (Step 4 and 5 GINA) asthma with at least blood eosinophilic count above 300 cells/mcl at least once in the previous year and ≥150 cells/mcl in the absence of systemic corticosteroid treatment before biological treatment initiation. In addition, one of the following conditions will be required: 1) ≥2 exacerbations in the previous year despite appropriate inhaled treatments or 2) the need for systemic corticosteroids on top of inhaled treatment for at least 6 months in the previous year.