Efficacy and safety of benralizumab in chronic rhinosinusitis with nasal polyps: A randomized, placebo-controlled trial

Background: Eosinophilic inflammation has been implicated in the pathogenesis, severity, and treatment responsiveness of chronic rhinosinusitis with nasal polyps (CRSwNP). Objective: We sought to assess the efficacy and safety of benralizumab-mediated eosinophil depletion for treating CRSwNP. Methods: The phase 3 OSTRO study enrolled patients with severe CRSwNP who were symptomatic despite treatment with intranasal corticosteroids and who had a history of systemic corticosteroid (SCS) use and/or surgery for nasal polyps (NP). Patients were randomized 1:1 to treatment with benralizumab 30 mg or placebo every 4 weeks for the first 3 doses and every 8 weeks thereafter. Coprimary end points were change from baseline to week 40 in NP score (NPS) and patient-reported mean nasal blockage score reported once every 2 weeks. Results: The study population comprised 413 randomized patients (207 in the benralizumab group and 206 in the placebo group). Benralizumab significantly improved NPS and nasal blockage score compared to placebo at week 40 (P <= .005). Improvements in Sinonasal Outcome Test 22 score at week 40, time to first NP surgery and/or SCS use for NP, and time to first NP surgery were not statistically significant between treatment groups. Nominal significance was obtained for improvement in difficulty in sense of smell score at week 40 (P = .003). Subgroup analyses suggested influences of comorbid asthma, number of NP surgeries, sex, body mass index, and baseline blood eosinophil count on treatment effects. Benralizumab was safe and well tolerated. Conclusion: Benralizumab, when added to standard-of-care therapy, reduced NPS, decreased nasal blockage, and reduced difficulty with sense of smell compared to placebo in patients with CRSwNP.