LAUSR

Rationale: Patients with Severe Eosinophilic Asthma (SEA) frequently have comorbid nasal polyps (NP). Treatment with mepolizumab may improve NP impact on health-related quality of life (HRQOL). Methods: MUSCA was a Phase IIIb, placebo-controlled, double-blind, parallel-group, multicenter study (NCT02281318); patients aged ≥12 years with SEA were randomized (1:1) to receive mepolizumab 100 mg (Mepo) or placebo (Pbo) subcutaneously, in addition to SoC, every 4 weeks for 24 weeks. The Sinonasal Outcomes Test (SNOT-22) was administered at baseline and 24 weeks. A post-hoc analysis of change from baseline in the SNOT-22 was conducted by the presence of nasal polyps at baseline. Results: Of the 556 patients randomized, 551 were included in the modified intent-to-treat population; 105 (19%) with NP and 446 (81%) without NP. Baseline scores for the SNOT-22 were 43.6 (SD 22.3) and 31.1 (SD 20.2) for those with and without NP. Among patients with NP, mean (SE) change from baseline was -13.7 (2.62) and -1.9 (2.96), for patients treated with Mepo and Pbo, respectively, with a treatment difference of -11.8 (95% Confidence Interval (95%CI) -19.8,-3.9) exceeding the minimal important difference (MID) of -8.9. Among patients without NP, mean (SE) changes were -8.6 (1.21) and -3.7 (1.18) for Mepo and Pbo, respectively, with a treatment difference of -4.9 (95%CI: -8.3,-1.6). Conclusions: In SEA patients with or without comorbid NP, Mepo vs. Pbo led to an improvement in rhinosinusitis HRQOL. The observed treatment effect on health impacts measured by the SNOT-22 in SEA patients with NP was larger than in those without and was clinically meaningful. Funding: GSK [200862; NCT02281318]