Mepolizumab Shows Real-World Effectiveness in Severe chronic Rhinosinusitis with Nasal Polyps: Study
A multicentre Italian study of 621 patients with severe, uncontrolled chronic rhinosinusitis with nasal polyps (CRSwNP) evaluated mepolizumab during the first 12 months of treatment. The study provides comprehensive real-world evidence of its effectiveness, while highlighting the substantial variability in outcomes across previous studies due to differences in patient selection, study design, follow-up and outcome measures. The study was published in The Lancet Respiratory Medicine by Prof. Eugenio De. And colleagues.
For the assessment of real-world 12-month outcomes, researchers designed an ambispective, multi-center phase 4 trial carried out across 25 Italian centers specialized in the treatment of severe CRSwNP and biological agents. In this study, 621 adults with severe, uncontrolled CRSwNP, treated with mepolizumab 100 mg subcutaneously every 4 weeks starting from December 1, 2023, to March 15, 2024 were recruited.
Clinical parameters such as total nasal polyp score (NPS), Sino-Nasal Outcome Test-22 (SNOT-22), olfaction, symptoms visual analogue scale (VAS) score, blood eosinophils count, and adverse events were measured at baseline and after 1, 3, 6, 9, and 12 months of treatment. Changes in NPS and SNOT-22 scores served as primary outcome measures, whereas further secondary analyses focused on disease control rate and remission induction, as well as subgroup response in asthma, NSAID-ERD, and previous biologic treatment populations.
Key findings:
- Monitoring of the 621 subjects over the 12-month time period provided detailed clinical, endoscopic, and safety parameters.
- Twelve months after enrolment into the study, a statistically significant reduction in nasal polyp score and SNOT-22 score was seen relative to baseline measurements (p<0.0001).
- While major sinonasal symptoms and overall sense of smell improved during the treatment period, 186 of 495 evaluable patients (38%) were still anosmic at 12 months of the treatment period.
- The disease control rate was achieved in 206 of 519 evaluable patients (42%) at 12 months, and 104 out of 519 patients (20%) had clinical characteristics indicating that the condition of the patients was on its way to the remission.
- Baseline higher visual analogue scale smell score and lower baseline SSIT-16 smell score were found to be negative predictors of disease control between 3 and 12 months of therapy, whereas baseline lower nasal polyp score was an independent predictor of progression toward remission at 12 months (OR 0.72; 95% CI 0.59-0.87, p=0.0008).
- Mepolizumab was safe, with adverse events occurring in only 29 of 621 patients (5%).
In summary, mepolizumab showed significant improvements in clinical, endoscopic, and quality-of-life parameters over the course of the first year of therapy in patients with severe and uncontrolled CRSwNP. It is important to note that the study’s conclusions highlight the need for further long-term and prospective trials for assessing multi-year remission rates; nevertheless, mepolizumab represents a promising biological therapy option.
Reference:
De Corso, E., Giancarlo, O., Seccia, V., Pipolo, C., Canevari, F. R. M., Giandomenico, M., Cantone, E., Fabio, P., Anastasi, F., Pasquini, E., Torretta, S., Garzaro, M., Gallo, S., Loperfido, A., D’Ascanio, Luca, Moffa, A., Cavaliere, C., Caruso, M., Anzivino, R., … Pacaj, K. (2026). Mepolizumab effectiveness for patients with severe, uncontrolled chronic rhinosinusitis with nasal polyps in Italy (MEPOREAL): a real-life, multicentre, phase 4 trial. The Lancet Respiratory Medicine. https://doi.org/10.1016/S2213-2600(26)00197-9
