Efficacy and Safety Study of Benralizumab Added to Medium-dose Inhaled Corticosteroid Plus LABA in Patients With Uncontrolled Asthma

Inclusion Criteria: 1. Provision of informed consent prior to any study specific procedures 2. Female and male aged from 18 to 75 years, inclusively 3. History of physician-diagnosed asthma requiring treatment with medium dose ICS (\>250ug fluticasone dry powder formulation equivalents total daily dose) and a LABA, for at least 12 months prior to Visit 1 4. Documented treatment with medium-dose ICS (\>250ug and ≤500ug fluticasone dry powder formulation equivalents total daily dose) and LABA for at least 3 month prior to Visit 1 Exclusion criteria: 1. Clinically important pulmonary disease other than asthma (e.g. active lung infection, COPD, bronchiectasis, pulmonary fibrosis, cystic fibrosis, hypoventilation syndrome associated with obesity, lung cancer, alpha 1 anti-trypsin deficiency, and primary ciliary dyskinesia) or ever been diagnosed with pulmonary or systemic disease, other than asthma, that are associated with elevated peripheral eosinophil counts (e.g. allergic bronchopulmonary aspergillosis/mycosis, Churg- Strauss syndrome, hypereosinophilic syndrome) 2. Any disorder, including, but not limited to, cardiovascular, gastrointestinal, hepatic, renal, neurological, musculoskeletal, infectious, endocrine, metabolic, haematological, psychiatric, or major physical impairment that is not stable in the opinion of the Investigator and could: - Affect the safety of the patient throughout the study - Influence the findings of the studies or their interpretations - Impede the patient's ability to complete the entire duration of study 3. Acute upper or lower respiratory infections requiring antibiotics or antiviral medication within 30 days prior to the date informed consent is obtained or during the screening/run-in period 4. Any clinically significant abnormal findings in physical examination, vital signs, haematology, clinical chemistry, or urinalysis during screening/run-in period, which in the opinion of the Investigator, may put the patient at risk because of his/her participation in the study, or may influence the results of the study, or the patient's ability to complete entire duration of the study