73 - Dupilumab Improves Histologic and Endoscopic Aspects of Eosinophilic Esophagitis (EoE), as Well as Rate of Weight Gain, in Children Aged 1 to <12 years: 52-week Results From the Phase 3 EoE KIDS Trial (Late-Breaking Abstract)

Mirna Chehade, MD, MPH¹, Evan S. Dellon, MD, MPH², Jonathan M. Spergel, MD, PhD³, Marc E. Rothenberg, MD, PhD⁴, Robert D. Pesek, MD⁵, Margaret H. Collins, MD⁴, Ikuo Hirano, MD⁶, Ruiqi Liu, PhD⁷, Elizabeth Laws, PhD⁸, Eric Mortensen, MD⁷, Renata Martincova, MD⁹, Jennifer Maloney, MD⁷, Eilish McCann, PhD⁷, Matthew P. Kosloski, PharmD, PhD⁷, Jennifer D. Hamilton, PhD⁷, Carin Samuely, MD⁷, Lila Glotfelty, MD, PhD⁸, Arsalan Shabbir, MD, PhD⁷; ¹Mount Sinai Center for Eosinophilic Disorders, Icahn School of Medicine at Mount Sinai, New York, NY; ²University of North Carolina School of Medicine, Chapel Hill, NC; ³Children’s Hospital of Philadelphia, Philadelphia, PA; ⁴Cincinnati Children’s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH; ⁵University of Arkansas for Medical Sciences and Arkansas Children's Hospital, Little Rock, AR; ⁶Northwestern University Feinberg School of Medicine, Chicago, IL; ⁷Regeneron Pharmaceuticals Inc., Tarrytown, NY; ⁸Sanofi, Bridgewater, NJ; ⁹Sanofi, Prague, Czech Republic

Introduction: There are no approved treatments for eosinophilic esophagitis (EoE) in children aged <12 years. Dupilumab blocks key type 2 inflammation drivers and is approved for EoE in patients (pts) aged ≥12 years and weighing ≥40kg in the USA. The Phase 3 EoE KIDS trial (NCT04394351) evaluated efficacy and safety of dupilumab in pts aged 1 to <12 years with EoE.

Methods: Part A was a 16 week (W), placebo-controlled study; pts were randomized 2:2:1:1 to weight-tiered, subcutaneous dupilumab on a higher-exposure (HE) or lower-exposure (LE) regimen, or placebo (2 groups). Patients who completed Part A could enter Part B, in which pts continued the same dupilumab regimen and pts on placebo switched to their pre-assigned HE or LE dupilumab dose to W52. This analysis includes pts assigned to HE dupilumab and placebo up to W52.

Results: All groups had generally similar baseline demographics, disease characteristics, and a high level of atopic comorbidities. At W16 in Part A, the HE dupilumab group met the primary endpoint of peak esophageal intraepithelial eosinophil (eos) count ≤6 eos/high-power field (hpf) vs placebo (least squares mean difference vs placebo [95% CI], 64.5 [48.19, 80.85], P<0.0001). At W52, 62.9% of pts receiving HE in Parts A and B and 52.9% of pts who switched from placebo in Part A to HE dupilumab in Part B achieved peak eos/hpf ≤6. At W16, the following measures improved from baseline with HE dupilumab vs placebo: EoE-Histologic Scoring System grade and stage scores (–0.88 and –0.84 vs +0.02 and +0.05, both P<0.0001); EoE-Endoscopic Reference Score (–3.5 vs +0.3, P<0.0001); change in body weight for age percentile (+3.09 vs +0.29); and numeric improvement in caregiver-reported proportion of days experiencing ≥1 EoE sign (-0.28 vs -0.17). At W52 in Part B, improvement in these endpoints was maintained or increased with continued HE dupilumab. Improvements were also observed in placebo pts switching to HE dupilumab (Table). At W16, adverse events more frequent with dupilumab vs placebo included COVID-19, rash, headache, and injection site erythema; safety profile was similar through W52.

Discussion: HE dupilumab met the primary endpoint of peak esophageal intraepithelial eos count ≤6 eos/hpf vs placebo and demonstrated significant and clinically meaningful changes in histologic and endoscopic outcomes, and improvements in clinical symptoms and rate of weight gain. Benefits were maintained or increased to W52 with continued treatment.

Acknowledgments: Research sponsored by Sanofi and Regeneron Pharmaceuticals Inc. ClinicalTrials.gov Identifier: NCT04394351. We would like to thank Faisal A. Khokhar of Regeneron Pharmaceuticals Inc. for their contribution to this analysis. Medical writing/editorial assistance provided by Chris Bulman, PhD, of Adelphi Communications, and funded by Sanofi and Regeneron Pharmaceuticals Inc., according to the Good Publication Practice guideline.


Disclosures: