Superior Benefits of Combining Mepolizumab With Sinus Surgery Compared to Mepolizumab Alone: Results From a Randomised 6-Month Trial.

Background: Chronic rhinosinusitis with nasal polyps (CRSwNP) significantly impacts patients' quality of life (QoL). Standard treatments include nasal irrigations, nasal steroids, systemic corticosteroids, and functional endoscopic sinus surgery (FESS). Uncontrolled severe CRSwNP treated with monoclonal antibodies (biologic drugs) gain better disease control, although some residual symptoms may persist. Combining biologic therapy with FESS could potentially reduce residual symptoms faster and for a longer period. Therefore, we aim to compare the effectiveness of combined FESS and biologic therapy against biologics alone in patients with severe CRSwNP.

Materials And Methods: This randomised controlled trial (RCT) enrolled 58 patients with CRSwNP and type 2 inflammation who were randomly assigned to FESS or non-FESS groups. All patients were treated with 100 mg of s.c. mepolizumab every 4 weeks for 6 months. Those in the FESS group underwent surgery 2 weeks after the first injection. Patients were assessed at baseline and after 6 months using the sino-nasal outcome test-22 (SNOT-22), visual analog scale (VAS), nasal congestion score (NCS), and the smell identification test (16 sticks). Clinical evaluations were performed using rhinoscopy to identify nasal polyp scores (NPS).

Results: Both treatment groups significantly improved in terms of their SNOT-22 scores after 6 months of treatment (p < 0.001). There were not significant differences between the two groups (p = 0.055). Patients with large NPS (6-8) improved significantly in terms of their SNOT-22 scores when they underwent combined treatment (FESS and mepolizumab) compared with s.c. mepolizumab alone (p < 0.05). They also exhibited improvements in ΔNPS (p < 0.001), VAS CRS (p = 0.074), and NCS reduction (p < 0.001) after undergoing combined treatment compared with those who had mepolizumab alone.

Conclusion: Patients with large polyp scores experienced significant improvements in their QoL (SNOT-22) and reduced NPS, NCS, and VAS CRS more when polyp burden was reduced with FESS in association with mepolizumab treatment compared to those treated with mepolizumab alone.