This is a study designed to evaluate efficacy and safety of Benralizumab in reducing the Oral Corticosteroid (OCS) use in adult patients with severe asthma who are receiving OCS with or without additional asthma controller medications.

This is an open-label, multicenter study designed to evaluate efficacy and safety of reducing daily oral corticosteroid (OCS) use after initiation of 30 mg dose of benralizumab administered subcutaneously (SC) in patients with severe eosinophilic asthma receiving high-dose inhaled corticosteroid (ICS)/long-acting β2 agonist (LABA) and OCS with or without additional asthma controller(s).

Inclusion Criteria:

1. Peripheral blood eosinophil count of ≥150 cells/μL assessed by central lab at Visit 1 or ≥ 300 cells/μL in the past 12 months
2. History of physician diagnosed asthma requiring continuous treatment with high dose ICS (high-dose ICS is budesonide/formoterol HFA ≥640/18 per day or equivalent, fluticasone propionate DPI > 500/day or equivalent, or authorized generics for these products) plus LABA for at least 6 months prior to Visit 1. The ICS and LABA can be contained within a combination product or given by separate inhalers. The ICS can also be given via nebulized solution for inhalation.
3. Chronic oral corticosteroid therapy equivalent to a daily dose of at least 5 mg of prednisone, for at least 3 continuous months directly preceding Visit 1.
4. Patient should be on a stable OCS dose for at least 4 weeks prior to Visit 1.
5. Non-smokers, current smokers or former smokers with a smoking history of < or =20 pack-years at Visit 1

Exclusion Criteria:

1. Clinically important pulmonary disease other than asthma or ever been diagnosed with pulmonary or systemic disease, other than asthma, that are associated with elevated peripheral eosinophil counts
2. Known history of allergy or reaction to the study drug formulation
3. History of anaphylaxis to any biologic therapy
4. A helminth parasitic infection diagnosed within 24 weeks prior to the date informed consent is obtained that has not been treated with, or has failed to respond to, standard of care therapy
5. Asthma exacerbation requiring use of systemic corticosteroids, or an increase in maintenance dose of OCS, or acute upper/lower respiratory infections requiring antibiotics or antiviral medication within 30 days prior to Visit 2 (first benralizumab dose)
6. A history of known immunodeficiency disorder including history of a positive human immunodeficiency virus (HIV) test
7. Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) level ≥3 times the upper limit of normal (ULN) confirmed at Visit 1.
8. Receipt of immunoglobulin or blood products within 30 days prior to the date informed consent is obtained
9. Coincident primary adrenal failure (Addison's disease) or irreversible secondary hypoadrenalism due to another independent cause (e.g. pituitary tumour or its treatment)
10. Co-existent inflammatory conditions for which chronic OCS doses are part of their maintenance treatment such as Giant Cell Arteritis, Polymyalgia Rheumatica
11. Exclusion from genetic research may be for any of the exclusion criteria specified in the main study or allogeneic bone marrow transplant, Non-leukocyte depleted whole blood transfusion within 120 days of genetic sample collection
12. Current night-shift workers

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal. All request will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA Pharma Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

When a request has been approved AstraZeneca will provide access to the de-identified individual patient-level data in an approved sponsored tool . Signed Data Sharing Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information. Additionally, all users will need to accept the terms and conditions of the SAS MSE to gain access. For additional details, please review the Disclosure Statements at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

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