Efficacy and Safety Study of Benralizumab in Patient With Eosinophilic Chronic Rhinosinusitis With Nasal Polyps (ORCHID)

Inclusion criteria: 1. Female or male patients aged 18 to 75 years inclusive 2. Stable Intranasal corticosteroids (INCS) use for at least 4 weeks prior to enrolment and throughout screening and DB period 3. History of treatment with systemic corticosteroids (SCS) or prior surgery for CRSwNP 4. Bilateral sinonasal polyposis with a nasal polyp score (NPS) of 5 at enrolment and randomization (unilateral score of at least 2 for each nostril) 5. Ongoing symptoms for at least 12 weeks prior to enrolment 6. Patient-reported moderate to severe nasal blockage score (NBS) ≥2 at enrolment 7. Bi-weekly mean NBS ≥ 1.5 at randomization 8. SNOT-22 total score ≥ 20 at enrolment and randomization 9. Documented physician-diagnosed asthma 10. Blood eosinophil count of \>2% or ≥150/μL at enrolment 11. LMS E≥M for Asian Exclusion criteria: 1. Any nasal and/or sinus surgery within 3 months prior to enrolment 2. Patients with conditions that makes them non evaluable for the co-primary efficacy endpoint including but not limited to: * Unilateral antrochoanal polyps * Nasal septal deviation that occludes at least one nostril * Current rhinitis medicamentosa * Allergic fungal rhinosinusitis or allergic fungal sinusitis; 3. Clinically important comorbidities (other eosinophil-driven diseases but CRSwNP) that may put the patient at risk, or may confound interpretation of clinical efficacy and/or safety results 4. Receipt of SCS for within 4 weeks prior to screening, or a scheduled SCS treatment during the study period. 5. Receipt of any marketed or investigational biologic product within 6 months of enrolment 6. Currently pregnant or breastfeeding