Biologic therapies targeting IL-5 or its receptor reduce eosinophilia and exacerbations in asthma. Breakthrough eosinophilic attacks are usually considered biologic failure. We report 2 patients with severe asthma receiving mepolizumab or benralizumab who developed relapsing hypereosinophilia associated with Pseudomonas aeruginosa airway infection. Case 1 was a 71-year-old woman in Canada with severe eosinophilic asthma and […]