Chronic rhinosinusitis with nasal polyps (CRSwNP) can be a severe and debilitating disease associated with significant morbidity, loss of smell, sinus pressure, and asthma exacerbations. Eosinophils play a role in the majority (85%) of patients. Benralizumab, an afucosylated monoclonal antibody directed against the IL-5 receptor has powerful apoptotic effects on eosinophils.
We sought to investigate the therapeutic benefit of inhibiting the IL-5 receptor using benralizumab to treat severe rhinosinusitis with nasal polyps.
Patients with severe NP (defined by endoscopic grade 5 or more out of 8) with elevated eosinophils and a history of previous surgical or endoscopic polypectomy met entry criteria and were randomized in a double-blind fashion to receive 30mg benralizumab SC or placebo. Endoscopic NP score was assessed at baseline and at treatment week 20. CT scan, SNOT-22 survey, and UPSIT smell test score changes were also evaluated.
Thirty-three patients were screened and twenty-four (n = 24) were enrolled in the study. Compared to baseline, benralizumab significantly improved NP score (-0.9±0.2, P=0.004) whereas placebo did not (-0.3±0.3, P=0.166). Benralizumab induced polyp size reduction compared to placebo did not reach statistical significance (P=0.103). Five of 12 benralizumab treated patients (42%) had improvements in all major outcomes (polyp score, CT, SNOT-22 and smell test) versus 2 out of 12 placebo (17%). The ratio of blood eosinophil count to allergen skin test positivity correlated with polyp reduction.
Benralizumab was well-tolerated and compared to baseline achieved a statistically significant reduction in nasal polyp size, sinus occupancy, symptoms, and improved sensation of smell for most patients (83%).