Safety and efficacy of anti-IL-5 monoclonal antibodies as second-line therapy for chronic rhinosinusitis with nasal polyps: a meta-analysis

Introduction This meta-analysis aimed to evaluate the safety and efficacy of anti-IL-5 monoclonal antibody (anti-IL-5 mAb) as a second-line therapy for chronic rhinosinusitis with nasal polyps (CRSwNP). Materials and methods Four databases (PubMed, Web of Science, Embase and Cochrane Library) were searched from the establishment of the databases to September 15, 2025, for randomized controlled trials (RCTs) comparing anti-IL-5 mAb versus placebo in the treatment of CRSwNP. The primary outcome measure of this meta-analysis were nasal polyp score (NPS) and Sino-Nasal Outcome Test-22 (SNOT-22) score. Secondary outcome measures included nasal blockage score (NBS), loss of smell score (LSS), Lund-Mackay score (LMS), University of Pennsylvania Smell Identification Test (UPSIT) score, nasal overall visual analog scale(VAS) score, nasal composite visual analog scale(VAS) score, number of first-time NP surgery patients and number of systemic corticosteroids (≥1 course) patients. Results Totally 10 RCTs were included for meta-analysis. Compared with placebo, anti-IL-5 mAb provided a significantly lower NPS (WMD = -0.58, 95%CI: -0.70 ~ -0.46, P < 0.00001, I 2 = 83%), SNOT-22 score (WMD: -9.57, 95% CI: -11.03 ~ -8.11, P < 0.00001, I 2 = 80%), NBS (SMD: -1.75; 95% CI: -3.13 ~ -0.36, P = 0.01, I 2 = 99%), LSS (SMD: -1.68; 95% CI: -3.13 ~ -0.24, P = 0.02, I 2 = 99%), LMS (WMD: -2.00; 95% CI: -2.65 ~ -1.34, P < 0.00001, I 2 = 97%), nasal overall VAS score (WMD: -1.54, 95% CI: -1.64 ~ -1.43, P < 0.00001, I 2 = 0%), nasal composite VAS score (WMD: -1.28, 95% CI: -1.66 ~ -0.19, P < 0.00001, I 2 = 0%), number of first-time NP surgery patients (RR: 0.64, 95% CI: 0.41 ~ 1.00, P = 0.05, I 2 = 69%) and number of systemic corticosteroids (≥1 course) patients (RR: 0.73, 95% CI: 0.62 ~ 0.86, P = 0.0002, I 2 = 0%), while significantly improved UPSIT (WMD: 2.09, 95% CI: 0.42 ~ 3.77, P = 0.01, I 2 = 0%). Conclusions This results confirmed that anti-IL-5 mAb therapy was safe and effective for CRSwNP and can serve as a second-line therapy. Systematic review registration https://www.crd.york.ac.uk/prospero/ , identifier CRD420251170717.