S892 Dupilumab Improves Endoscopic Features of Eosinophilic Esophagitis (Edema, Rings, Exudates, Furrows, and Strictures): Pooled Analysis From 2 Phase 3 Studies (EoE KIDS and LIBERTY EoE TREET)

Introduction: The Endoscopic Reference Score (EREFS) measures the severity of 5 endoscopic features found in children and adults with eosinophilic esophagitis (EoE): edema, rings, exudates, furrows, and strictures. Here, we describe EREFS in children, adolescents, and adults treated with dupilumab vs placebo from a pooled analysis of the EoE KIDS (NCT04394351) and LIBERTY EoE TREET (NCT03633617) studies. Methods: Patients from Part A of EoE KIDS randomized to weight-tiered, higher-exposure dupilumab or placebo for 16 weeks, and patients from Parts A/B of LIBERTY EoE TREET randomized to weekly dupilumab 300 mg or placebo for 24 weeks, were included. EREFS scores were based on the worst observed region calculated using the highest (most severe) score for each feature from either the proximal or distal esophagus (range 0-9: edema [0-1], rings [0-3], exudates [0-2], furrows [0-2], strictures [0-1]). EREFS total and individual feature scores, and the proportion of patients with scores of 0 (absent) in each feature, were assessed at baseline and week 16 or 24, the respective end of each study’s double-blind treatment period). All P-values are nominal. Results: In the pooled cohort, 159 patients received dupilumab and 152 received placebo. Baseline characteristics were generally comparable between dupilumab and placebo groups: mean EREFS total score 4.0 (95% confidence interval 3.7, 4.3) and 4.1 (3.8, 4.3), inflammatory score 2.6 (2.4, 2.7) and 2.6 (2.4, 2.7), and fibrostenotic score 1.6 (1.4, 1.7) and 1.6 (1.5, 1.8), respectively. At week 16 or 24, EREFS total score was reduced with dupilumab vs placebo (1.5 [1.3, 1.8] vs 3.9 [3.6, 4.2], P < 0.0001), as were scores for each feature. The proportion of patients scoring 0 for a given feature increased with dupilumab treatment when comparing week 16 or 24 vs baseline (edema 44.8 vs 13.0%; rings 57.7 vs 44.2%; exudates 89.5 vs 33.8%; furrows 68.5 vs 9.1%; strictures 93.7 vs 79.2%). In addition, a greater proportion of patients had no edema, rings, exudates, or furrows when comparing dupilumab vs placebo at week 16 or 24. Conclusion: In this pooled analysis of 2 phase 3 studies involving children, adolescents, and adults, dupilumab improved endoscopic features vs placebo. Dupilumab also increased the proportion of patients with no edema, rings, exudates, furrows, or strictures at first-endoscopic assessment (16 or 24 weeks), suggesting an effect on endoscopic healing.