New England Journal of Medicine.
and eosinophilic inflammation, according to results from two phase 3 trials. The data were published in theBenralizumab, an interleukin-5 receptor alpha–directed cytolytic monoclonal antibody, is approved for the treatment of patients with severe eosinophilic asthma. To assess whether the treatment may prevent COPD exacerbations, Gerard J. Criner, MD, chair and professor of thoracic medicine and surgery at Temple University in Philadelphia and colleagues conducted two randomized, double-blind, parallel-group studies: GALATHEA and TERRANOVA. Researchers enrolled patients with frequent moderate or severe COPD exacerbations and blood eosinophil counts of at least 220 per mm3.
A 56-week treatment period
“An eosinophil threshold of 220 per mm3 was selected on the basis of the phase 2 trial of benralizumab in patients with COPD, in which modeling of annual exacerbations according to baseline blood eosinophil count indicated that patients with eosinophil counts above a similar threshold were more likely to have a response to benralizumab,” the authors wrote. “The doses selected were 30 mg, the approved dose for asthma treatment; 100 mg, to inform the safety margin; and 10 mg (in TERRANOVA), to evaluate the dose-efficacy relationship.”
Patients received placebo or benralizumab via subcutaneous injection every 4 weeks for the first three doses, then every 8 weeks for the rest of the 56-week treatment period. The primary end point was the annualized COPD exacerbation rate ratio (benralizumab vs. placebo) at week 56.
The primary analysis populations included 1,120 patients in GALATHEA and 1,545 patients in TERRANOVA. Most patients were white men, and the average age was 65 years. The percentages of patients with current asthma (5.4% in GALATHEA and 3.3% in TERRANOVA) or past asthma (8.3% in GALATHEA and 6.1% in TERRANOVA) were low.
In GALATHEA, the estimated annualized exacerbation rates were 1.19 per year in the 30-mg benralizumab group, 1.03 per year in the 100-mg benralizumab group, and 1.24 per year in the placebo group. Compared with placebo, the rate ratio was 0.96 for 30 mg of benralizumab and 0.83 for 100 mg of benralizumab.
In TERRANOVA, the estimated annualized exacerbation rates for 10 mg, 30 mg, and 100 mg of benralizumab and for placebo were 0.99 per year, 1.21 per year, 1.09 per year, and 1.17 per year, respectively. The corresponding rate ratios were 0.85, 1.04, and 0.93. “At 56 weeks, none of the annualized COPD exacerbation rate ratios for any dose of benralizumab as compared with placebo reached significance in either trial,” the researchers said. “Types and frequencies of adverse events were similar with benralizumab and placebo.”