Background: This study aims to evaluate the efficacy and safety of mepolizumab in the treatment of severe uncontrolled CRSwNP with or without comorbid asthma in a real-life setting over the first six months of therapy. Methods: A total of 45 patients with nasal polyps with or without comorbid asthma were treated with mepolizumab (100 mg q4w) for 6 months. The following outcomes were assessed before therapy (V⁰), and after 6 months (V¹): endoscopic nasal polyp score (NPS), nasal congestion score (NCS), sinonasal outcome test (SNOT-22), visual analog scale (VAS), nasal flow rate (PNIF), olfactory test (SS-I), and asthma control test (ACT). Blood eosinophil count, oral steroid intake, and rescue surgery were also measured. Results: We found a statistically significant improvement in NPS, NCS, SNOT-22, overall VAS, PNIF, SS-I, and ACT. In addition, we observed a decrease in blood eosinophils count. Mepolizumab was well tolerated, and no patients interrupted the treatment during the follow up. Conclusions: Our real-life study confirmed the efficacy and tolerance of mepolizumab prescribed for CRSwNP with or without asthma. The safety profile of mepolizumab was consistent with previous reports.

Background/Objectives: Dupilumab is a human monoclonal antibody that targets both IL-4 and IL-13 signaling. Eosinophilia has been reported as a potential adverse event in treated patients in randomized controlled trials and 12-month real-life studies. This real-life, 24-month prospective study investigated the prevalence of eosinophilia, its consequences, and the effectiveness of dupilumab in a cohort of patients with severe asthma, chronic rhinosinusitis with nasal polyps, and atopic dermatitis. Methods: A total of 66 adult patients treated with dupilumab were included in this study. ACT, SNOT-22, and Smell-VAS, EASI, and absolute blood eosinophil count (AEC) were assessed according to the type of diagnosis at baseline (T0), after 6 (T6), 12 (T12), 18 (T18), and 24 (T24) months post-dupilumab initiation. Results: All patients experienced significant improvement in both symptoms and disease control following dupilumab treatment. A total of 27 out of 66 (40.9%) patients developed eosinophilia within six months of treatment (AEC T6 mean ± SD 0.67 ± 0.68 10⁹/L). Eosinophilia was generally mild and lasted on average for six months (AEC T12 mean ± SD 0.66 ± 0.65 10⁹/L) with AEC normalization after 18 months of treatment (AEC T18 mean ± SD 0.58 ± 0.48 10⁹/L). Ten patients (15.15%) developed hypereosinophilia, but no symptoms or signs of eosinophilic-related organ damage have been observed, with no need for dupilumab discontinuation. Conclusions: Dupilumab-related eosinophilia was common, generally mild, and transient, whereas persistent hypereosinophilia occurred in a small group of patients in the absence of symptoms or signs of eosinophilic damage.