A randomized trial of benralizumab, an antiinterleukin 5 receptor alpha monoclonal antibody, after acute asthma

Background: Patients with frequent asthma exacerbations resulting in emergency department (ED) visits are at increased risk for future exacerbations. We examined the ability of 1 dose of benralizumab, an investigational antiinterleukin 5 receptor a monoclonal antibody, to reduce recurrence after acute asthma exacerbations. Methods: In this randomized, double-blind, placebo-controlled study, eligible subjects presented to the ED with an asthma exacerbation, had partial response to treatment, and greater than or equal to 1 additional exacerbation within the previous year. Subjects received 1 intravenous infusion of placebo (n = 38) or benralizumab (0.3 mg/kg, n= 36 or 1.0 mg/kg, n= 36) added to outpatient management. The primary outcome was the proportion of subjects with greater than or equal to 1 exacerbation at 12 weeks in placebo vs the combined benralizumab groups. Other outcomes included the time-weighted rate of exacerbations at week 12, adverse events, blood eosinophil counts, asthma symptom changes, and health care resource utilization. Results: The proportion of subjects with greater than or equal to 1 asthma exacerbation at 12 weeks was not different between placebo and the combined benralizumab groups (38.9% vs 33.3%; P = .67). However, compared with placebo, benralizumab reduced asthma exacerbation rates by 49% (3.59 vs 1.82; P = .01) and exacerbations resulting in hospitalization by 60% (1.62 vs 0.65; P = .02) in the combined groups. Benralizumab reduced blood eosinophil counts but did not affect other outcomes, while demonstrating an acceptable safety profile. Conclusions: When added to usual care, 1 dose of benralizumab reduced the rate and severity of exacerbations experienced over 12 weeks by subjects who presented to the ED with acute asthma. (C) 2014 Elsevier Inc. All rights reserved.