This is a Phase IIIb, randomized, double-blind, placebo controlled, parallel group study designed to evaluate the efficacy and the safety of repeat dosing of benralizumab 30 mg subcutaneous (sc) versus placebo on top of standard of care asthma therapy in patients with severe uncontrolled asthma. Approximately 630 patients with peripheral blood eosinophil counts ≥150 cells/μL will be randomized 2:1 to receive benralizumab 30 mg sc or matched placebo for 24 weeks.
After enrolment, eligible patients will enter an up to 42-day screening/run-in period. Patients who meet eligibility criteria will be randomized 2:1 on Day 0 to receive either benralizumab or placebo every 56 days (every 8 weeks) through Week 16, with end of treatment (EOT) at Day 168 (Week 24). At the completion of the 24-week doubleblind period of the ANDHI study, eligible patients in benralizumab and placebo arm may enter a 56-week open label period (ANDHI in Practice [ANDHI IP] substudy), in which concomitant asthma therapies will be tapered as directed by the protocol in those patients who achieve and maintain asthma control (defined as ACQ6 score <1.5 and no clinically significant asthma exacerbations that required a burst of systemic corticosteroid or a hospitalization due to asthma between reduction visits) with add-on benralizumab.