BENRALIZUMAB INTENDED FOR EOSINOPHILIC ASTHMA LEADS TO COMPLETE RESOLUTION OF EOSINOPHILIC EOSPHAGITIS

Introduction A patient with severe eosinophilic asthma and eosinophilic esophagitis (EoE) with significant prompt improvement after initiating Benralizumab, anti-IL 5 therapy. Case Description We present a 64-year old female with a significant history of eosinophilic asthma and EoE. Her asthma failed optimal inhaled controller treatment, requiring monthly oral steroid rescue courses and frequent emergency department visits and hospital admissions. She was highly allergic to environmental and perennial allergens, but was unable to tolerate allergy immunotherapy due to adverse reactions. Additionally, she was having difficulty swallowing for over a decade with confirmed EoE on biopsy. By the time of diagnosis, she already had an esophageal stricture, requiring multiple dilations. Her maternal aunt and maternal grandfather died after choking on food. She started swallowed steroids and a six food elimination diet with mild improvement but continued having episodes of choking and difficulty swallowing. Benralizumab was prescribed for her eosinophilic asthma. Approximately two weeks after her first treatment, her esophageal symptoms of dysphagia and sensation of food getting stuck completely resolved. Her asthma slowly improved and months later, her EoE remains symptom free with no eosinophils found on repeat esophageal biopsy. Discussion Current and previous clinical trials have shown mixed results with anti IL-5 therapy in EoE. Studies using Mepolizumab and Reslizumab have shown significant reduction in esophageal eosinophilia, however, with inconsistent clinical benefit. Benralizumab, directly targets eosinophils for ADCC, depletes eosinophils with low levels of IL-5Rα expression and those that are independent of IL-5. The depleting effect of Benralizumab on eosinophils is particularly rapid and pronounced.