Treatment with benralizumab was associated with statistically significant improvements in nasal polyp size and nasal blockage in patients with chronic rhinosinusitis with nasal polyps (CRSwNP), according to findings from the phase 3 OSTRO trial.

The 56-week, multicenter, double-blind study evaluated the efficacy and safety of benralizumab, an interleukin-5 antagonist, in 413 adult patients with severe nasal polyposis who were symptomatic despite standard of care therapy, including current use of intranasal corticosteroids and prior surgery and/or use of systemic corticosteroids. Patients were randomized to receive either benralizumab 30mg subcutaneously every 4 weeks for the first 3 doses, then every 8 weeks thereafter or placebo. The coprimary end points were change from baseline in the endoscopic total nasal polyp score (NPS) and mean nasal blockage score (NBS) at week 40. 

Results showed statistically significant improvements in both the endoscopic total NPS and mean NBS at week 40 in patients treated with benralizumab compared with placebo. As for safety, benralizumab was found to be consistent with its known safety profile.

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Benralizumab is marketed under the trade name Fasenra (AstraZeneca) and is currently indicated as an add-on maintenance treatment of severe asthma in patients aged ≥12 years, and with an eosinophilic phenotype.

“The OSTRO results show that Fasenra’s eosinophil-depleting mechanism of action may benefit patients with this often debilitating condition,” said Professor Claus Bachert, Head of the Department of Oto-Rhino-Laryngology and Chair of the Upper Airway Research Laboratory, University Hospital Ghent, Belgium, the principal investigator of the trial.

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Fasenra met both co-primary endpoints of reduced nasal polyp size and blockage in the OSTRO Phase III trial for patients with chronic rhinosinusitis with nasal polyps. Accessed September 10, 2020.