BACKGROUND: In placebo-controlled trials, reslizumab, an anti-IL-5 monoclonal antibody, significantly reduced asthma exacerbations and improved lung function and asthma control in patients with eosinophilic asthma.OBJECTIVE: This open-label extension study evaluated safety and efficacy of reslizumab for up to 24 months.METHODS: After participation in 1 of 3 placebo-controlled, phase III trials in moderate-to-severe eosinophilic asthma, patients received reslizumab 3.0 mg/kg intravenously every 4 weeks for up to 24 months. Adverse events (AEs), lung function, and patient-reported asthma control were evaluated.RESULTS: In the open-label extension, 1,051 patients received ?1 reslizumab dose (480 reslizumab-na?ve, 571 reslizumab-experienced); median (range) exposure was 319 (36-840) and 343 (36-863) days in reslizumab-na?ve and reslizumab-experienced patients, respectively. Continuous exposure, including during the placebo-controlled studies, was ?12 months for 740 patients and ?24 months for 249 patients. The most common AEs were worsening of asthma and nasopharyngitis. Serious AEs affected 78 of 1,051 (7%) patients; 18 of 1,051 (2%) discontinued treatment because of AEs; and there were 3 deaths (all non-treatment-related). Fifteen adult patients (15 of 1,023; 1%) had malignancies of diverse tissue types. Reslizumab-experienced patients maintained improved lung function and asthma control; reslizumab-na?ve patients had improvements in these measures throughout open-label treatment. Blood eosinophil counts appeared to be returning to baseline after reslizumab discontinuation.CONCLUSIONS: In patients with moderate-to-severe eosinophilic asthma, intravenous reslizumab 3.0 mg/kg displays favorable long-term safety and sustained long-term efficacy. Initial improvements in lung function and asthma control were maintained for up to 2 years. These findings substantially add to our understanding of the long-term safety and efficacy of anti-IL-5 strategies.
Adolescent Adult