IMPROVEMENT IN MORNING PEAK EXPIRATORY FLOW WITHIN THE FIRST WEEK OF TREATMENT WITH IV RESLIZUMAB

Introduction In duplicate 52-week placebo (PBO)-controlled Phase 3 trials, patients with inadequately controlled eosinophilic asthma (blood eosinophils ≥400 cells/µL) who received reslizumab (RES; 3mg/kg IV Q4W) achieved significant improvements in FEV 1 , FVC and FEF 25-75% 4 weeks after the first dose. The objective of this post-hoc analysis was to assess earlier improvements in lung function based on ambulatory morning peak expiratory flow (PEF). Methods Patients used a PEF meter and recorded their pre-dose (prior to use of long-acting beta agonists and inhaled corticosteroids) PEF daily throughout the trials (Study 1 and Study 2). PEF technique was reviewed at scheduled clinic visits. Weekly averages of daily morning PEF measurements are reported. Results Study 1 included 489 patients (PBO 244, RES 245) and Study 2 included 464 patients (PBO 232, RES 232). Patients receiving RES demonstrated increases in mean morning PEF (L/min) versus placebo of 22.66±7.85 and 18.90±9.28 (p=0.004; p=0.042) at 52 weeks in Study 1 and Study 2, respectively. Improvement compared with placebo was evident within the first week (RES vs PBO, Study 1: 1.18±4.78 vs -8.22±4.02; Study 2: 0.850±6.03 vs -8.18±4.55). Between-treatment differences increased through week 7 (RES vs PBO, Study 1: 15.82±6.29 vs -10.98±5.41; Study 2: 27.33±8.06 vs -6.97±6.01) and were sustained through the 52-week treatment period. PEF improvements corresponded with FEV 1 improvements at Week 4. Conclusions Treatment with IV RES was associated with rapid and sustained improvement in lung function as assessed by morning PEF in patients with severe eosinophilic asthma, confirming earlier FEV 1 data. Overall change from baseline over 52 weeks of treatment in Studies 1 and 2, weekly average AM Peak Expiratory Flow Rate (PEFR) (L/min)