ABSTRACT: Background Data on mepolizumab in patients with severe eosinophilic asthma (EA) and comorbidities are needed to assess whether randomized controlled trial results are applicable in the real world. Objective To evaluate real-life effectiveness and the presence/absence of predictors of treatment response in patients with one or more comorbidities (nasal polyps, allergic rhinitis, gastro-esophageal reflux disease, nonallergic rhinitis with eosinophilia syndrome, obesity, bronchiectasis) who received mepolizumab (MEPO) for the treatment of severe EA. Methods We performed a single-center retrospective study in patients with severe asthma and presence of comorbidities treated with mepolizumab at the respiratory outpatient clinic, Policlinico-Vittorio Emanuele, Catania, Italy. Health records of 31 severe asthmatic patients were retrieved and analyzed. Asthma control test (ACT) score, blood eosinophil count, forced expiratory volume in 1 s (FEV1), FEV1% of predicted and FEV1/FVC (Forced Vital Capacity) ratio, oral corticosteroid (OCS) dosage, and exacerbations were recorded at baseline (T0), after 3 (T1), 6 (T3), 9 (T6), and 12 months (T12). Clinical response was defined when 3 of these 4 criteria were fulfilled: i) 30% exacerbation decrease; ii) 80% blood eosinophilia reduction; iii) 3 point ACT increase; iv) FEV1 increase ?200 mL. Results 83.87% of patients were classified as responsive to MEPO treatment. Substantial depletion of the blood eosinophils (>80%) was found in 87.1% of patients, FEV1 > 200 mL was seen in 54.84% of patients, a 3-point ACT improvement from baseline was recorded in 80.65% 25 of patients and a 30% reduction of exacerbations rates was seen in 96.77% of patients. Moreover, the majority 38.71% of patients met 3/4 parameters after 12 months. Neither the comorbidities nor other characteristics (sex, BMI, age, smoking) influenced treatment response. Conclusions MEPO in patients with severe EA is effective regardless of the presence of comorbidities.
