The Phase III COPD clinical programs conducted with the anti‐eosinophil therapies benralizumab and mepolizumab showed no evidence of increased exacerbations or bacterial infections compared to placebo,40, 41 supporting that IL‐5 and/or eosinophils are not directly responsible for the higher immunoglobulin levels seen in our eosinophilhigh COPD patients. Here, IL5 is linked to bacterial infectious disease.