262. DUPILUMAB REDUCED EOSINOPHIL COUNTS AND IMPROVED HISTOLOGY GRADE/STAGE SCORES IN PATIENTS WITH EOSINOPHILIC ESOPHAGITIS: LIBERTY EOE TREET RESULTS

Abstract

Abstract Background In the 3-part, phase 3 LIBERTY EoE TREET study (NCT03633617) dupilumab 300 mg weekly (qw) demonstrated significant improvements in symptoms and eosinophil counts, and clinically meaningful improvement in endoscopic features vs placebo, in adults and adolescents with EoE. The objective of this analysis was to further assess the effect of dupilumab vs placebo on histologic aspects of disease in Parts A and B of LIBERTY EoE TREET. Methods Patients aged ≥12 years were randomized 1:1 to dupilumab 300 mg qw or placebo. Endpoints (at Week 24) were the proportion of patients achieving ≤1, ≤6, and < 15 eosinophils per high-power field (eos/hpf), change from baseline in peak eosinophil count and Histologic Scoring System (HSS) scores, specifically the severity (grade) and extent (stage) of abnormality of the 8 components (basal zone hyperplasia [BZH], eosinophil inflammation [EI], eosinophil abscess [EA], eosinophil surface layering [ESL], dilated intercellular spaces [DIS], surface epithelial alteration [SEA], dyskeratotic epithelial cells [DEC], and lamina propria fibrosis [LPF]). P-values are nominal unless otherwise specified. Results Dupilumab significantly increased the proportion of patients achieving ≤1, ≤6, and < 15 eos/hpf in Part A (P < 0.0001, P < 0.05, and P < 0.0001, respectively) and Part B (all P < 0.0001) vs placebo. Percent change in peak eosinophil count from baseline and HSS grade/stage scores were significantly improved with dupilumab vs placebo for Parts A and B (all P < 0.0001) (Table). Significant improvements were observed for the histologic components BZH, EI, EA, ESL, SEA grade/stage scores (P < 0.0001) in both Parts, DIS grade score in Part A (P < 0.05), and DEC grade/stage scores in Part B (P < 0.05); other components showed numeric improvements. Dupilumab was generally well tolerated. Conclusions Dupilumab 300 mg qw significantly decreased eosinophil counts and improved the severity and extent of histologic aspects of the disease as measured by HSS versus placebo in adults and adolescents with EoE up to 24 weeks, documenting a more global improvement in addition to eosinophil counts. Overall safety was consistent with the known dupilumab safety profile.