Reslizumab for Inadequately Controlled Asthma with Elevated Blood Eosinophil Levels : a Randomized Phase 3 Study

BACKGROUND: This phase 3 study further characterizes the efficacy and safety of reslizumab (a humanized anti-interleukin-5 monoclonal antibody) in patients aged 12-75 years with asthma inadequately controlled by at least a medium-dose inhaled corticosteroid, and blood eosinophils ≥400cells/μL.METHODS: Patients were randomized to receive reslizumab 0.3 or 3.0mg/kg or placebo once/every 4 weeks/16 weeks. Primary endpoint was change from baseline in pre-bronchodilator forced expiratory volume in 1 sec (FEV1) over 16 weeks. Secondary endpoints included forced vital capacity (FVC), forced expiratory flow at 25-75% of FVC (FEF25-75%), patient-reported control of asthma symptoms, short-acting beta agonist (SABA) use, blood eosinophil levels, and safety.RESULTS: Reslizumab significantly improved FEV1 (difference vs placebo [reslizumab 0.3 and 3.0mg/kg]:115mL[95% CI 16-215; P= .0237] and 160mL[95% CI 60-259; P= .0018]). Clinically meaningful increases in FVC (130mL) and FEF25-75% (233mL/s) were observed with reslizumab 3.0mg/kg. Reslizumab improved Asthma Control Questionnaire (ACQ) and Asthma Quality of Life Questionnaire (AQLQ) versus placebo (greater effects seen with 3.0mg/kg; P