A Study of Benralizumab in Patients With Eosinophilic Esophagitis

Inclusion Criteria:

• Patients 12 to 65 years of age, inclusive, at the time of signing the informed consentor assent (if applicable) form.
• Documented previous diagnosis of EoE by endoscopy.
• Must be symptomatic at Visit 1 (screening) and Visit 2 (randomization):

1. A patient reported an average of at least 2 days per week with an episode ofdysphagia over the 4 weeks prior to Visit 1 AND
2. An average of at least 2 days per week with an episode of dysphagia (Daily DSQ ≥2) between Visit 1 and Visit 2, and at least 2 days per week with an episode ofdysphagia (Daily DSQ ≥2) in each of the 2 weeks immediately prior torandomization

• May be on background medications for EoE and related treatments during the study aslong as the background medications have been stable for at least 4 weeks (8 weeks forPPI) prior to the screening and there is agreement not to change type of backgroundmedication or dosage during the run-in period and for the first 52 weeks of the studyunless a change is medically indicated.
• Negative serum pregnancy test for female patients of childbearing potential at Visit1.
• Women of childbearing potential must agree to use a highly effective form of birthcontrol (confirmed by the Investigator) from randomization throughout the studyduration and within 12 weeks after last dose if IP.

Exclusion Criteria:

• Other GI disorders such as active Helicobacter pylori infection, history of achalasia,esophageal varices, Crohn's disease, ulcerative colitis, inflammatory bowel disease,or celiac disease.
• Esophageal stricture that prevents the easy passage of a standard endoscope or anycritical esophageal stricture that requires dilation during the run-in period.
• Esophageal dilation performed within 8 weeks prior to screening and prior esophagealsurgery that would impact the assessments for EoE
• Use of a feeding tube, or having a pattern of not eating solid food daily during therun-in period.
• Hypereosinophilic syndrome, defined by multiple organ involvement and persistent bloodeosinophil count >1500 eos/μL.
• EGPA vasculitis.
• Eosinophilic gastritis, gastroenteritis, enteritis, or colitis documented by biopsy.
• Current malignancy, or history of malignancy with some specific exceptions.
• History of anaphylaxis to any biologic therapy or vaccine.
• Current active liver disease:
• Chronic stable hepatitis B and C (including positive testing for hepatitis Bsurface antigen [HBsAg] or hepatitis C antibody), or other stable chronic liverdisease are acceptable if patient otherwise meets eligibility criteria.
• Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) level ≥3 timesthe upper limit of normal (ULN), confirmed by repeated testing during the run-inperiod.
• Helminth parasitic infection diagnosed within 24 weeks prior to the date informedconsent or assent (if applicable) is obtained that has not been treated with or hasfailed to respond to standard of care therapy.
• History of known immunodeficiency disorder including a positive human immunodeficiencyvirus (HIV) test.
• Concomitant use of immunosuppressive medication.
• Initiation or change of a food-elimination diet regimen or reintroduction of apreviously eliminated food group in the 6 weeks prior to start of the run-in period.
• Currently pregnant, breastfeeding, or lactating women.