A Study of CDX-0159 in Patients With Eosinophilic Esophagitis

Key Inclusion Criteria 1. ≥ 18 years of age 2. Documented diagnosis of eosinophilic esophagitis (EoE) by endoscopy 3. Peak esophageal intraepithelial eosinophil count (PEC) of ≥ 15 per high power field (hpf) from at least 2 of 3 levels (proximal, mid, and distal) of the esophagus 4. Symptomatic, defined as • Average of ≥ 2 days per week with dysphagia with solid food intake in the 1 month prior to Screening, and • ≥ 4 days with dysphagia within the last 2 weeks prior to randomization 5. On a stable diet which includes solid foods for ≥ 2 months prior to Screening (and throughout the study) 6. Inadequate response to or is inappropriate for and/or intolerant to a standard-of-care treatment for EoE (e.g., PPI, swallowed topical corticosteroids, or dietary elimination) 7. Willing to be compliant with completion of daily questionnaire Key Exclusion Criteria 1. Diagnosed with hypereosinophilic syndrome or Churg-Strauss syndrome (eosinophilic granulomatosis with polyangiitis) 2. History of clinicopathologic diagnosis of eosinophilic gastritis or eosinophilic duodenitis 3. Known active Helicobacter pylori infection 4. History of coagulation disorders, esophageal varices, achalasia, Crohn's disease, ulcerative colitis, or celiac disease 5. Esophageal dilation within 3 months prior to Screening 6. Prior esophageal or gastric surgery that would confound the assessments of EoE 7. Esophageal stricture that is difficult to pass with a standard adult upper endoscope (9 to 10 mm) or stricture that requires dilation at the Screening EGD 8. Avoiding solid foods or using a feeding tube 9. Regular use of antiplatelet and/or anticoagulant therapy 10. Non-biologic systemic agents within 2 months prior to Screening, including but not limited to corticosteroid (oral, swallowed topical or parenteral), non-steroidal immunosuppressants (e.g., methotrexate, cyclosporin, tacrolimus, mycophenolate mofetil, azathioprine), other immunomodulators (e.g., Jak inhibitors, tyrosine kinase inhibitors), and investigational agents 11. Biologic therapy within 5 half-lives (or detectable serum level) prior to Screening, including but not limited to interleukin (IL)-4 receptor inhibitor (dupilumab), IL-5 inhibitors (e.g., mepolizumab, benralizumab), IL-13 inhibitors (e.g., tralokinumab, lebrikizumab), anti-IgE (e.g., omalizumab), IFN-γ inhibitors, or other approved or investigational biologics 12. Oral immunotherapy (OIT) within 6 months prior to Screening 13. Sublingual immunotherapy (SLIT) and/or subcutaneous immunotherapy (SCIT) Note: Not exclusionary if patient has been on a stable maintenance dose for at least 6 months prior to Screening 14. Receipt of a live vaccine within 2 months prior to the Baseline (Day 1) Visit (patients must agree to avoid live vaccination during study treatment and within 3 months thereafter). 15. Diagnosis of idiopathic anaphylaxis or other severe allergic reactions that in the opinion of the investigator, could increase the patient's risk for systemic hypersensitivity reactions 16. Prior receipt of barzolvolimab There may be additional criteria your study doctor will review with you to confirm eligibility