STEP: Phase IIIb Study of Benralizumab to Step-down Maintenance Therapy in Patients With Severe Eosinophilic Asthma

The study population will be approximately 440-520 patients on MD/HD ICS/LABA with and without LTRA or LAMA or theophylline and meeting study inclusion and exclusion criteria in China. After patients sign the informed consent, they will undergo a screening visit (Visit 1, Week -1 to Week 0) to assess eligibility criteria. Patients who meet eligibility criteria and complete study baseline assessments will enter the study and receive the first dose of benralizumab at visit 2 (Week 0). The benralizumab treatment includes 4 phases: Induction Phase (16 weeks), Reduction Phase (24 weeks), Maintenance Phase (16 weeks) and Follow-up Phase (4 weeks). After initiation of benralizumab 30 mg administered subcutaneously every 4 weeks (Q4W) for the first 3 doses (Visits 2 to 4), then every 8 weeks (Q8W) thereafter.