100% OF PATIENTS ACHIEVED SUBSTANTIAL HISTOLOGICAL RESPONSE BY WEEK 52

DUPIXENT significantly reduced peak esophageal intraepithelial eosinophil count vs placebo at Week 24 (Part B) with sustained results at Week 52 (Part C)

PROPORTION OF PATIENTS WHO ACHIEVED HISTOLOGICAL RESPONSE OR REMISSION FROM
BASELINE THROUGH WEEK 52 (PART B/C)^1,a

Improvements in swallowing vs placebo in Parts A, A/C^a

• 82% of patients achieved response (<15 EOS/HPF) and 59% achieved remission (≤6 EOS/HPF) at Week 24 with DUPIXENT vs 11% response and 5% remission with placebo (P<0.001)^2,d

Proportion of patients who achieved histological response and remission rates from baseline in Parts A, A/C

• 64% of patients achieved response (<15 EOS/HPF) and 60% achieved remission (≤6 EOS/HPF) at Week 24 with DUPIXENT (n=42) vs 8% response and 5% remission with placebo (n=39) (P<0.0001)²
• 82% of patients who received DUPIXENT from baseline achieved histological response at Week 52 (n=40), and 70% of patients who switched to DUPIXENT from placebo at Week 24 achieved histological response (n=37)²
• 56% of patients who received DUPIXENT from baseline achieved histological remission at Week 52 (n=40), and 60% of patients who switched to DUPIXENT from placebo at Week 24 achieved histological remission (n=37)²

Peak esophageal intraepithelial eosinophil count determines histologic outcome, using both percent change in peak EOS/HPF, as well as proportion of patients achieving a treatment response.

Histologic response is defined as ‹15 EOS/HPF, histologic remission as ≤6 EOS/HPF.

^a Secondary endpoints were the proportion of patients achieving peak esophageal intrepithelial eosinophil count of <15 EOS/HPF at Week 24, and the proportion of patients achieving s6 EOS/HPF at Weeks 24 and 52.

^b 100% of patients who received DUPIXENT from baseline achieved histological response (n=74), and 78% of patients who switched to DUPIXENT from placebo at Week 24 achieved histological response (n=37).

^c 85% of patients who received DUPIXENT from baseline achieved histological remission at Week 52 (n=74), and 68% of patients who switched to DUPIXENT from placebo at Week 24 achieved histological remission (n=47).

^d Coprimary endpoint was the proportion of patients achieving peak esophageal intraepithelial eosinophil count of ≤6 EOS/HPF at Week 24.

EOS/HPF, eosinophils per high-power field.

PROPORTION OF PATIENTS WHO ACHIEVED COMPLETE REMISSION RATES
(<1 EOS/HPF) FROM BASELINE THROUGH WEEK 24 (PART A)^1,a

^a 29% of patients who received DUPIXENT from baseline achieved complete remission at Week 52 (n=34), and 27% of patients who switched to DUPIXENT from placebo at Week 24 achieved complete remission (n=30) (secondary endpoint).

^b Patients with missing values at Week 24 were considered non-responders.

^c Based on a study in 62 adults with EoE treated with TCS or elimination diets. For the complete resolution of fibrotic features of EoE, a cut point of 0 EOS/HPF with associated AUC of 0.68 best predicted this outcome. 

AUC, area under the curve; EoE, eosinophilic esophagitis; EOS/HPF, eosinophils per high-power field; TCS, topical corticosteroids.

Reference:

1. Dellon ES, Rothenberg ME, Collins MH, et al. Dupilumab in adults and adolescents with eosinophilic esophagitis. N Engl J Med. 2022;387(25):2317-2330. doi:10.1056/NEJMoa2205982

COMPREHENSIVE HISTOLOGIC REMISSION SIMPLE BEYOND EOSINOPHIL DEPLETION¹

DUPIXENT significantly improved histology vs placebo at Week 24 (Part B)

IMPROVEMENT IN SEVERITY (GRADE) AND EXTENT (STAGE) OF HISTOLOGICAL ABNORMALITIES  AT WEEK 24 (PART B)^a

Improvement in EoE-HSS grade and stage score in Parts A,A/C¹

• 60% improvement from baseline at Week 24 in EoE-HSS grade score in patients who received DUPIXENT (n=35) and <1% improvement in patients who received placebo (n=26)
• 58% improvement from baseline at Week 24 in EoE-HSS stage score in patients who received DUPIXENT (n=35) and <1% improvement in patients who received placebo (n=26)
• 69% improvement from baseline at Week 52 in EoE-HSS grade score in patients who received DUPIXENT for 52 weeks (n=37) and 66% improvement in patients who switched from placebo to DUPIXENT at Week 24 (n=40)
• 69% improvement from baseline at Week 52 in EoE-HSS stage score in patients who received DUPIXENT for 52 weeks (n=37) and 63% improvement in patients who switched from placebo to DUPIXENT at Week 24 (n=40)

^a Secondary endpoints were the severity of histological abnormalities (grade) and the extent of histological abnormalities (stage) at Week 24.

^b EoE-HSS remission is defined as both EoE-HSS grade and stage scores <3 and peak eosinophil count <15 EOS/HPF.

^c Proportion of patients in histopathologic remission with DUPIXENT VS placebo at Week 24 (64% VS 8% in Part A, 83% VS 8% in Part B). For patients on continuous DUPIXENT treatment from baseline at Week 52, EoE-HSS remission was achieved by 82% in Part A/C, 100% in Part B/C; among patients who switched from placebo to DUPIXENT at Week 24, the proportion in remission also increased at Week 52 (to 70% and 78%, respectively).

DUPIXENT NORMALIZED KEY HISTOPATHOPHYSIOLOGIC FEATURES OF EoE

DUPIXENT led to a greater proportion of patients achieving total resolution of most histologic features vs placebo at Week 24^2,3

^a DUPIXENT-patients/placebo-patients: EI, EA & SL, 74/73; SEA, BZH, DIS & DEC, 74/72; LPF, 31/34.

^b All effects were maintained or improved further with continued DUPIXENT QW (n=74) at Week 52; improvements in most EoE-HSS components were observed in patients who switched from placebo to DUPIXENT at Week 24 (n=37).

BZH, basal zone hyperplasia; DEC, dyskeratotic epithelial cells; DIS, dilated intercellular spaces; EA, eosinophil abscess; EoE-HSS, Eosinophilic Esophagitis-Histology Scoring System; El, eosinophil inflammation; LPF, lamina propria fibrosis; QW, once weekly; SEA, surface epithelial alteration; SL, eosinophil surface layering.

EoE HISTOLOGY SCORING SYSTEM (EoE-HSS) FEATURES BEYOND EOSINOPHIL COUNT⁴:

Features of Esophageal Biopsy

References:

1. Dellon ES, Rothenberg ME, Collins MH, et al. Dupilumab in adults and adolescents with eosinophilic esophagitis. N Engl J Med.
   2022;387(25):2317-2330. doi:10.1056/NEJMoa2205982
2. Collins MH, Gonsalves NP, Ashok D, et al. Dupilumab normalizes key histopathologic features of eosinophilic esophagitis: post hoc analysis of the phase 3 LIBERTY EoE TREET study. Poster Sa1260. Presented at Digestive Diseases Week (DDW) 2025; May 3-6, 2025; San Diego, CA.
3. Collins MH, Rothenberg ME, Lerner D, et al. Dupilumab improves histopathologic endpoints in children with eosinophilic esophagitis: 52-week results from the phase 3 EoE KIDS trial. Poster presented at: Digestive Disease Week (DDW) 2024; May 18-21, 2024; Washington, DC.
4. Collins MH, Martin LJ, Alexander ES, et al. Newly developed and validated eosinophilic esophagitis histology scoring system and evidence that it outperforms peak eosinophil count for disease diagnosis and monitoring. Dis Esophagus. 2016;30(3):1-8.
   doi:10.1111/dote.12470

TREET STUDY DESIGN^1,2

Coprimary endpoints:

• Histological remission (peak esophageal intraepithelial eosinophil count ≤6 EOS/HPF) at Week 24
• Change from baseline in DSQ score at Week 24

Secondary endpoints:

• Percent change from baseline in peak esophageal intraepithelial eosinophil count
• Absolute change from baseline in EoE-HSS mean grade score
• Absolute change from baseline in EoE-HSS mean stage score
• Absolute change from baseline in EoE-EREFS
• Proportion of patients achieving peak esophageal intraepithelial eosinophil count of <15 EOS/HPF

DSQ, Dysphagia Symptom Questionnaire; EoE-HSS, eosinophilic esophagitis histology scoring system; EREFS, Endoscopic Reference Score; EOS/HPF, eosinophils per high-power field; QW, once weekly.

References:

1. DUPIXENT Summary of Product Characteristics, 2026.
2. Dellon ES, Rothenberg ME, Collins MH, et al. Dupilumab in adults and adolescents with eosinophilic esophagitis. N Engl J Med.
   2022;387(25):2317-2330. doi:10.1056/NEJMoa2205982

DUPIXENT DELIVERS RAPID AND SUSTAINED DYSPHAGIA RELIEF

DUPIXENT significantly reduced dysphagia vs placebo as early as Week 24 (Part B), with lasting improvement through Week 52 (Part C)^1-3

DYSPHAGIA SYMPTOM QUESTIONNAIRE (DSQ) TOTAL SCORE IN PARTS B, B/C^1-3,a

Improvement in swallowing vs placebo in Parts A, A/C^1,a

• 28% reduction in dysphagia with DUPIXENT (n=42) at Week 4 vs 10% with placebo (n=39)
• 67% reduction in dysphagia with DUPIXENT (n=42) at Week 24 vs 27% with placebo (n=39)
• 76% reduction in dysphagia at Week 52 with DUPIXENT from baseline (n=40), and 66% reduction in patients who switched to DUPIXENT from placebo at Week 24 (n=37)

The Dysphagia Symptom Questionnaire (DSQ) is a patient-reported assessment that measures the frequency and severity of dysphagia. DSQ scores range from 0 to 84, with a lower score indicating less frequent or less severe dysphagia.

^aChange in DSQ from baseline to Week 24 was a coprimary endpoint.

QW, once weekly.

References:

1. Rothenberg ME, Dellon ES, Collins MH, et al. Efficacy and safety of dupilumab up to 52 weeks in adults and adolescents with eosinophilic oesophagitis (LIBERTY EoE TREET study): a multicentre, double-blind, randomised, placebo-controlled, phase 3 trial. Lancet Gastroenterol Hepatol. 2023;8(11):990-1004. doi:10.1016/S2468-1253(23)00204-2
2. DUPIXENT Summary of Product Characteristics, 2026.
3. Dellon ES, Rothenberg ME, Collins MH, et al. Dupilumab in adults and adolescents with eosinophilic esophagitis. N Engl J Med. 2022;387(25):2317-2330.doi:10.1056/NEJMoa2205982

DUPIXENT IMPROVES DIFFICULTY AND PAIN WITH SWALLOWING

DUPIXENT increased the number of dysphagia-free and odynophagia-free days vs placebo at Weeks 24 and 52^1,a,b

Proportion of patients with complete resolution of dysphagia days²

• 35% of patients with 0 dysphagia days in the preceding 14 days with DUPIXENT (n=37), vs 18% with placebo (n=33) at Week 24 (Part A)
• 35% of patients with O dysphagia days in the preceding 14 days with DUPIXENT (n=65), vs 11% with placebo (n=62) at Week 24 (Part B)

^a The number of days without dysphagia (Dysphagia Symptom Questionnaire (DSQ] question 2) and number of days without odynophagia (DSQ question 4;answered only if dysphagia was reported in question 2) over a 14-day period were analyzed every 2 weeks to Week 52

^b Odynophagia outcomes were assessed only in patients with 21 day of odynophagia in the 14 days before baseline.

^c At Week 52, 55% of patients who received DUPIXENT QW since baseline and 35% of patients who switched from placebo to DUPIXENT QW at Week 24 lad complete resolution of dysphagia days (Part A); 0 dysphagia days in 50% and 46% of patients, respectively (Part B)

Odynophagia, retrosternal pain when swallowing; QW, once weekly.

References:

1. Dellon ES, Gupta M, Chehade M, et al. Sustained treatment response with dupilumab in dysphagia and odynophagia in adults and adolescents with eosinophilic esophagitis: post hoc analysis of the LIBERTY EoE TREET study up to 52 weeks. Poster P107. Presented at: 2025 American College of Gastroenterology (ACG) Annual Scientific Meeting; October 24-29, 2025; Phoenix, AZ.
2. Dellon ES, Chehade M, Schoepfer AM, Liberty EoE TREET Group, Mccann E. Dupilumab improves multiple aspects of dysphagia symptoms in a randomized trial of eosinophilic esophagitis. Clin Gastroenterol Hepatol. 2025:S1542-3565(25)00932-2. doi:10.1016/j.cgh.2025.10.023

DUPIXENT IMPACTS EoE BY REDUCING SYMPTOM FREQUENCY 

DUPIXENT significantly improved non-dysphagia symptom frequency vs placebo at Week 24 (Part B)¹

IMPROVEMENT IN NON-DYSPHAGIA SYMPTOM FREQUENCY AT WEEK 24 (PART B)

1.4X improvement in symptom frequency with DUPIXENT vs placebo (P<0001)^a

The 5-Item EoE Symptom Questionnaire (EoE-SQ-Frequency) is a patient-reported assessment that measures the frequency of symptoms other than dysphagia or swallowing pain. The maximum score is 25, with higher scores indicating greater symptom severity and frequency.

^a As measured by EoE-SQ Frequency score, LSM change from baseline with DUPIXENT: -3.9 (n=80, baseline score: 12.1) vs -2.6 with placebo (n=79, baseline score: 11.4).

^b As measured by EoE-SQ Frequency score, median change from baseline to Week 52 with DUPIXENT: -4.0 (n=74, baseline score: 12.1) and -3.0 in placebo patients who switched to DUPIXENT at Week 24 (n=37, baseline score: 11.4).

EoE, eosinophilic esophagitis; LSM, least squares mean.

References:

1. Dellon ES, Rothenberg ME, Collins MH, et al. Dupilumab in adults and adolescents with eosinophilic esophagitis. N Engl J Med.
   2022;387(25):2317-2330. doi:10.1056/NEJMoa2205982
2. Rothenberg ME, Dellon ES, Collins MH, et al. Efficacy and safety of dupilumab up to 52 weeks in adults and adolescents with eosinophilic oesophagitis (LIBERTY EoE TREET study): a multicentre, double-blind, randomised, placebo-controlled, phase 3 trial.
   Lancet Gastroenterol Hepatol. 2023;8(11):990-1004. doi:10.1016/S2468-1253(23)00204-2

DUPIXENT DOES MORE TO REDUCE EoE SYMPTOM SEVERITY

DUPIXENT significantly improved non-dysphagia symptom severity vs placebo at Week 24 (Part B)¹

IMPROVEMENT IN NON-DYSPHAGIA SYMPTOM SEVERITY AT WEEK 24 (PART B)

1.5X improvement in non-dysphagia symptom severity with DUPIXENT VS placebo at Week 24 (Part B) (P<0001)^a

The severity of each symptom over 7 days was evaluated on a 10-point scale (0 = no symptom or minimal severity to 10 = high severity).

The EoE-SQ severity score was calculated from the sum of the severity scores for 3 symptoms (chest pain, stomach pain, burning feeling in the chest) (range: 0 to 30; higher scores indicating greater severity).

^a Change from baseline (1.3) to Week 24: -5.4 with DUPIXENT (n=80) vs -4.0 with placebo (n=79) (other secondary endpoint).

^b As measured by the EoE-SQ-Severity score, median change from baseline (1.3) to Week 52: -6.0 with DUPIXENT QW/QW (n=74) and -5.0 in the placebo/DUPIXENT QW group (n=37).

EoE-SQ, eosinophilic esophagitis symptom questionnaire; QW, once weekly.

References:

1. Dellon ES, Rothenberg ME, Collins MH, et al. Dupilumab in adults and adolescents with eosinophilic esophagitis. N Engl J Med.
   2022;387(25):2317-2330. doi:10.1056/NEJMoa2205982
2. Rothenberg ME, Dellon ES, Collins MH, et al. Efficacy and safety of dupilumab up to 52 weeks in adults and adolescents with eosinophilic oesophagitis (LIBERTY EoE TREET study): a multicentre, double-blind, randomised, placebo-controlled, phase 3 trial.
   Lancet Gastroenterol Hepatol. 2023;8(11):990-1004. doi:10.1016/S2468-1253(23)00204-2

VISIBLE IMPROVEMENT IN SEVERITY OF ENDOSCOPIC SIGNS

DUPIXENT significantly improved endoscopic findings (EREFS) vs placebo at Week 24 (Part B), with continued improvement at Week 52 (Part B/C)

Week 24 (DUPIXENT vs placebo) in Part B^1,a

• 66% improvement in EREFS from baseline vs 8% with placebo (P<0.01)^b

Week 52 (all patients on DUPIXENT) in Part B/C^1,2

• Up to 85% improvement in EREFS from baseline^c

RESULTS YOU CAN SEE IN REAL DUPIXENT PATIENTS

Improvement in endoscopy findings (EREFS) vs placebo in Parts A, A/C¹

• 49% improvement at Week 24 with DUPIXENT (n=42) vs 5% with placebo (n=29) (P<0.001)
• 63% improvement at Week 52 in patients who received DUPIXENT from baseline (n=40), and 65% improvement in patients who switched to DUPIXENT from placebo at Week 24 (n=37)

EoE-Endoscopic Reference Score (EREFS) correlates with proximal, mid, and distal eosinophilia and accurately measures the disease severity and treatment response of 5 endoscopic findings-edema (0-1), rings (043), exudates (0-2), furrows (0-2), and stricture (0-1)— grading separately for each third of the esophagus. Scores range from O to 18, with a higher score indicating higher severity/presence!

^a Secondary endpoint was change from baseline in EREFS at Week 24.

^b 66% reduction at Week 24 with DUPIXENT (n=80) vs 8% with placebo (n=79).

^c 78% reduction in patients who received DUPIXENT from baseline (n=63), and 85% reduction in patients who switched to DUPIXENT from placebo at Week 24 (n=37).

EREFS IS USED TO DETERMINE THE SEVERITY OF 5 ENDOSCOPIC FINDINGS IN EoE^3,a

^a There are other versions of EREFS, but this one was used for the LIBERTY TREET and EoE KIDS trials.

EoE, eosinophilic esophagitis.

References:

1. Dellon ES, Rothenberg ME, Collins MH, et al. Dupilumab in adults and adolescents with eosinophilic esophagitis. N Engi J Med.2022;387(25):2317-2330. doi:10.1056/NEJMoa2205982
2. Rothenberg ME, Dellon ES, Collins MH, et al. Efficacy and safety of dupilumab up to 52 weeks in adults and adolescents with eosinophilic oesophagitis (LIBERTY EoE TREET study): a multicentre, double-blind, randomised, placebo-controlled, phase 3 trial.Lancet Gastroenterol Hepatol. 2023;8(11):990-1004. doi:10.1016/S2468-1253(23)00204-2
3. Kia L, Hirano I. Advances in the endoscopic evaluation of eosinophilic esophagitis. Curr Opin Gastroenterol. 2016;32(4):325-331.doi:10.1097/MOG.0000000000000281

VISIBLE IMPROVEMENT IN BOTH INFLAMMATORY AND FIBROSTENOTIC SUBSCORES: THAT'S MORE THAN FINE

DUPIXENT significantly improved inflammatory and fibrostenotic EREFS subscores vs placebo at Week 24, with continuous improvement through Week 52^1,a-e

Post hoc analysis. Results are descriptive. Definitive conclusions cannot be made.

^aEREFS inflammatory subscore: edema, exudates, furrows, scored 0-5 in the worst observed region; EREFS fibrostenotic subscore: rings and strictures, scored 0-4 in the worst observed region.

^bPercent change in EREFS inflammatory subscore at Week 52, in Part A/C: -63% with DUPIXENT QW since baseline (n=33) and -59% in patients who switched from placebo to DUPIXENT QW at Week 24 (n=29).

^cPercent change in EREFS inflammatory subscore at Week 52, in Part B/C: -76% with DUPIXENT QW since baseline (n=61) and -76% in patients who switched from placebo to DUPIXENT QW at Week 24 (n=37).

^dPercent change in EREFS fibrostenotic subscore at Week 52, in Part A/C: -39% with DUPIXENT QW since baseline (n=23) and -46% in patients who switched from placebo to DUPIXENT QW at Week 24 (n=19).

^ePercent change in EREFS fibrostenotic subscore at Week 52, in Part B/C: -55% with DUPIXENT QW since baseline (n=41) and -67% in patients who switched from placebo to DUPIXENT QW at Week 24 (n=24).

^fPercent changes in individual elements of the EREFS inflammatory subscore at Week 52 with DUPIXENT QW since baseline (Part B/C, n=65): edema, -53%; exudates, -90%; furrows, -83%.

^gPercent change in individual elements of the EREFS fibrostenotic subscore at Week 52 with DUPIXENT QW since baseline (Part B/C, n=65): rings, -50%; strictures, -72%.

EREFS PHENOTYPES DID NOT IMPACT EFFICACY IN SYMPTOMS, HISTOLOGIC, AND ENDOSCOPIC FINDINGS

DUPIXENT improved symptoms, histologic remission rate, and EREFS total score vs placebo at Week 24, regardless of inflammatory or mixed phenotypes^2,a-e

^a Inflammatory phenotype: (edema ≥1, or exudates ≥1, or furrows ≥1) AND (rings =0 AND strictures =O); Mixed phenotype: (edema ≥1, or exudates ≥1, or furrows 21) and (rings 21, or strictures 21).

^b Proportion of patients with histologic remission (≤6 EOS/HPF) at Week 24 in patients with an inflammatory phenotype with DUPIXENT QW (n=39): 51% vs placebo (n=40): 5%; and in patients with a mixed phenotype with DUPIXENT QW (n=76) 62% vs 7% with placebo (n=76).

^c Absolute reduction in DSQ score at Week 24 in patients with an inflammatory phenotype with DUPIXENT QW (n=39): -24.27 vs placebo (n=40): -13.56; and in patients with a mixed phenotype with DUPIXENT QW (n=76): -1997 vs placebo (n=76): -9.89.

^d Absolute reduction in EREFS inflammatory subscore at Week 24 in patients with an inflammatory phenotype with DUPIXENT QW (n=39): -3.31 vs placebo (n=40): -0.51; and in patients with a mixed phenotype with DUPIXENT QW (n=76): -3.14 vs placebo (n=76): - 0.37.

^e LSM change from baseline in EREFS fibrostenotic subscore at Week 24 in patients with an inflammatory phenotype with DUPIXENT QW (n=39): +0.22 vs placebo (n=40): +0.51; and in patients with a mixed phenotype with DUPIXENT QW (n=76): -1.52 vs placebo (n=76): - 0.56.

^f Proportion of patients with histologic remission (≤6 EOS/HPF) at Week 52 in patients with an inflammatory phenotype with DUPIXENT QW/DUPIXENT QW (n=37): 66% and with placebo/DUPIXENT QW (n=25): 71%; and in patients with a mixed phenotype with DUPIXENT QW/DUPIXENT QW (n=70): 79% and with placebo/DUPIXENT QW (n=48): 60%.

^g Mean change from baseline at Week 52 in DSQ score in patients with an inflammatory phenotype with DUPIXENT QW/DUPIXENT QW (n=37): -32.16 and with placebo/DUPIXENT QW (n=25): -25.73; and in patients with a mixed phenotype with DUPIXENT QW/DUPIXENT (n=70): -26.56 and with placebo/DUPIXENT OW (n=48): -24.04.

^hAbsolute reduction in EREFS total score at Week 52 in patients with an inflammatory phenotype with DUPIXENT QW/DUPIXENT QW (n=37): -4.30 and with placebo/DUPIXENT QW (n=25): -4.30; and in patients with a mixed phenotype with DUPIXENT QW/DUPIXENT QW (n=70): -5.50 and with placebo/DUPIXENT QW (n=48): -6.10.

DSQ, Dysphagia Symptom Questionnaire; EOS/HPF, eosinophils per high-power field; EREFS, Endoscopic Reference Score; LSM, least squares mean; QW, once weekly.

References:

1. Hirano I, Dellon ES, Pellegatta G, et al. Dupilumab improves inflammatory and remodeling aspects of endoscopic disease activity in eosinophilic esophagitis: 52-week results from the phase 3 LIBERTY EoE TREET study. Poster 15. Presented at: Society of Gastroenterology Nurses and Associates (SGNA) 52nd Annual Course; June 1-3, 2025; Pittsburgh, PA.
2. Savarino EV, Peterson K, Zerbib F, et al. Dupilumab is efficacious regardless of endoscopic phenotype: post hoc analysis of the LIBERTY EoE TREET study. Presented at: 27th Annual Congress for the European Society for Disease of the Esophagus (ESDE) 2025; May 11-13, 2025; Amsterdam, the Netherlands.

DUPIXENT OFFERED GREATER IMPROVEMENT IN ENDOSCOPIC FINDINGS AT WEEK 16 (CHILDREN 1 TO 11 YEARS) OR WEEK 24 (12+ YEARS)¹

EREFS, Endoscopic Reference Score; QW, once weekly.

References:

1. Dellon ES, Chehade M, Gonsalves N, et al. Dupilumab improves edema, rings, exudates, furrows, and strictures on endoscopy: pooled analysis from two phase 3 studies (EoE Kids and LIBERTY EoE TREET). Poster Sa1277 presented at: Digestive Disease Week (DDW) 2025; May 3-6, 2025; San Diego, CA.
2. Dellon ES, Gupta SK. A conceptual approach to understanding treatment response in eosinophilic esophagitis. Clin Gastroenterol Hepatol. 2019;17(11):2149-2160. doi:10.1016/j.cgh.2019.01.030

QUALITY-OF-LIFE CHANGES THAT FREE PATIENTS TO LIVE BEYOND EoE

DUPIXENT significantly improved quality of life vs placebo at Week 24 (Part B)

1.5x  improvement in quality of life with DUPIXENT vs placebo (P<0.001)1,a

The 11-item EoE Impact Questionnaire (EoE-IQ) is a patient-reported assessment that measures health-related impacts of EoE. Patients record responses to questions that evaluate quality of life using a 5-point response option: ranging from "Not at all" to "Extremely." The maximum score is 5, with higher scores indicating a greater impact on quality of life.

^a Change at Week 24: - 0.89 with DUPIXENT (n=80) from baseline (2.2) vs -0.58 placebo (n=79) from baseline (2.3) (other secondary endpoint).

^b Improvements to individual items of the EoE-IQ were particularly seen in items relating to emotional status; patients on DUPIXENT QW had significantly less sleep disruption than those who received placebo.

^c At Week 12, LSM difference with DUPIXENT QW (n=42) vs placebo (n=39): -0.39 (95% Cl: -0.63, -0.15).

EoE, eosinophilic esophagitis; LSM, least squares mean; QW, once weekly.

Reference:

1. Dellon ES, Rothenberg ME, Collins MH, et al. Dupilumab in adults and adolescents with eosinophilic esophagitis. N Engl J Med. 2022;387(25):2317-2330. doi:10.1056/NEJMoa2205982

86% OF CHILDREN ACHIEVED HISTOLOGICAL RESPONSE AT WEEK 52

DUPIXENT significantly reduced peak esophageal intraepithelial eosinophil count vs placebo at Week 16 and sustained results through Week 52¹

PROPORTION OF CHILDREN WHO ACHIEVED HISTOLOGICAL REMISSION AND RESPONSE RATES FROM BASELINE THROUGH WEEK 52¹

Peak esophageal intraepithelial eosinophil count (eosinophils per high-power field, or EOS/HPF) determines histologic outcome, using both percent change in peak EOS/HPF as well as proportion of patients achieving a treatment response.

Histologic response is defined as <15 EOS/HPF, histologic remission as ≤6 EOS/HPF.

^a 86% of patients who received DUPIXENT from baseline achieved histologic response (n=35) and 65% of patients who switched from placebo to DUPIXENT at Week 16 (n=17) achieved histologic response at Week 52.

^b 63% of patients who received DUPIXENT from baseline achieved histologic remission (n=35) and 53% of patients who switched from placebo to DUPIXENT at Week 16 (n=17) achieved histologic remission at Week 52.

^c Primary endpoint was the proportion of patients achieving peak esophageal intraepithelial eosinophil count of ≤6 EOS/HPF at Week 16.

^d Secondary endpoints were the proportion of patients achieving peak esophageal intraepithelial eosinophil count of ≤6 EOS/HPF at Week 52 and proportion of patients achieving peak esophageal intraepithelial eosinophil count <15 EOS/HPF at Weeks 16 and 52.

^e At Week 100,91% and 68% of patients who received DUPIXENT from Week 16 (n=22) achieved histologic response and histologic remission, respectively.

Only DUPIXENT normalized histologic findings at Week 16, with continued improvement through Week 52

* 34% of patients who received DUPIXENT from baseline achieved histologic normalization (n=35) and 35% of patients who switched from placebo to DUPIXENT at Week 16 (n=17) achieved histologic normalization at Week 52.

References:

1. Chehade M, Dellon ES, Velpari S, et al. Dupilumab for eosinophilic esophagitis in patients 1 to 11 years of age. N Engl J Med. 2024;390:2239-2251. doi:10.1056/NEJMoa2312282
2. DUPIXENT Summary of Product Characteristics, 2026.
3. Chehade M, Dellon ES, Pesek RD, et al. Long-term dupilumab maintains histologic and endoscopic improvements in children with eosinophilic esophagitis (EoE): 100-Week results from the open-label extension (OLE) of the EoE KIDS study. Poster presented at: Digestive Disease Week (DDW) 2024; May 18-21, 2024; Washington, DO
4. Collins MH, Rothenberg ME, Lerner D, et al. Dupilumab improves histopathologic endpoints in children with eosinophilic esophagitis: 52-week results from the phase 3 EoE KIDS trial. Poster presented at: Eastern Food Allergy & Comorbidity Conference (EFACC); January 9-12, 2025; Palm Beach, FL.

HISTOLOGIC RESPONSE BEYOND EOSINOPHIL REDUCTION

DUPIXENT showed significant efficacy vs placebo, even in the deepest layers, at Week 16¹

IMPROVEMENT IN SEVERITY (GRADE) AND EXTENT (STAGE) OF HISTOLOGICAL ABNORMALITIES AT WEEK 52 (PART B)^1,a,b

^a Eo grade score from baseline at Week 52 in patients who received DUPIXENT during 52 weeks: -0.97 (n=37, baseline of 1.3) and -0.89 in patients who received placebo and switched to DUPIXENT at Week 16 (n=18, baseline 1.3).

^b EoE stage score from baseline at Week 52 in patients who received DUPIXENT during 52 weeks: -0.89 (n=37, baseline of 1.3) and - 0.86 in patients who received placebo and switched to DUPIXENT at Week 16 (n=18, baseline 1.3).

^c Eo grade score, change from baseline at Week 16 with DUPIXENT (n=37, baseline of 1.3): -0.88 vs placebo (n=34, baseline of 1.3); +0.02. LSM difference vs placebo: -0.90 (95% CI, -1.03 to -0.77), P<0.001 (secondary endpoint).

^d EoE stage score, change from baseline at Week Week with DUPIXENT DUPIXENT baseline of of - -0.84 vs placebo (n=34, baseline of 1.3); +0.05. LSM difference vs placebo: -0.88 (95% Cl, -1.01to -0.76), P<0.001 (secondary endpoint)

^e EoE-HSS grade score change from baseline at Week 100 in all patients with DUPIXENT (n=22): -0.85.

^f EoE-HSS stage score change from baseline at Week 100 in all patients with DUPIXENT (n=22): -0.87.

EoE-HSS, Eosinophilic Esophagitis-Histology Scoring System; LSM, least squares mean.

References:

1. Chehade M, Dellon ES, Spergel JM, et al. Dupilumab for eosinophilic esophagitis in patients 1 to 11 years of age. N Engl J Med.2024;390(24):2239-2251. doi:10.1056/NEJMoa2312282
2. Chehade M, Dellon ES, Pesek RD, et al. Long-term dupilumab maintains histologic and endoscopic improvements in children with eosinophilic esophagitis (EoE): 100-Week results from the open-label extension (OLE) of the EoE KIDS study. Poster presented at:
   European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) 2025; May 14-17, 2025; Helsinki, Finland.

KIDS STUDY DESIGN

Part A evaluated DUPIXENT vs matching placebo at dosing regimens based on body weight (≥15 kg to <30 kg, 200 mg Q2W; ≥30 to <60 kg, 300 mg Q2W)'. The recommended dosing regimen of DUPIXENT selected for pediatric patients 1 to 11 years of age weighing ≥40 kg was 300 mg QW.'

Q2W, once every 2 weeks; QW, once weekly.

References:

1. DUPIXENT Summary of Product Characteristics, 2026.
2. Chehade M, Dellon ES, Velpari S, et al. Dupilumab for eosinophilic esophagitis in patients 1 to 11 years of age. N Engl J Med. 2024;390(24):2239-2251. doi:10.1056/NEJMoa2312282
3. Chehade M, Dellon ES, Pesek RD, et al. Long-term dupilumab maintains histologic and endoscopic improvements in children with eosinophilic esophagitis (EoE): 100-week results from the open-label extension (OLE) of the EoE KIDS study. Poster presented at:
   European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) 2025; May 14-17, 2025; Helsinki, Finland.

DUPIXENT DELIVERS RESULTS CAREGIVERS CAN SEE AND CHILDREN CAN FEEL

DUPIXENT offered improvement in number of days with EoE signs at Week 16, and continued improvement through Week 52, as measured by PESQ-C

^a PESQ-C LSM percent change from baseline at Week 16: -49% with DUPIXENT (n=37) vs - 20% with placebo (n=34), (secondary endpoint).

^b PESQ-C LSM change from baseline at Week 16 in food refusal: DUPIXENT (n=31): -30.23% vs placebo (n=30): -12.37% (LSM difference vs placebo: -17.86% (95% Cl: -49.23 to 13.50]); in trouble swallowing: DUPIXENT (n=31): -27.42% vs placebo (n=30): -12.57% (LSM difference vs placebo: -14.85% [95% Cl: -55.57 to 25.88]); and reflux: DUPIXENT (n=31): -21.68% vs placebo (n=30): -10.36% (LSM difference vs placebo: -11.32% [95% Cl: -43.54 to 20.91]).

^c PESQ-C percent change from baseline at Week 52 in patients taking DUPIXENT (n=37): 81%; and in patients who switched to DUPIXENT from placebo at Week 16: 83%.

^dNumber of symptom-free days at Week 52 in patients who received DUPIXENT since baseline: 12.1 (n=37, baseline of 76), and in patients who switched from placebo to DUPIXENT at Week 16: 12.1 (n=18, baseline of 6.5).

^ePESQ-C percent change from baseline at Week 52 in patients who received DUPIXENT since baseline: stomach pain, -94.35%; heartburn, -93.33%; acid reflux, -58.08%; regurgitation, -85.90%; vomiting, -29.49%; food refusal, -83.76%; trouble swallowing, - 85.90%.

PESQ-C is a questionnaire intended for use by caregivers of patients ages 1 to 12 years to assess occurrence of signs of EoE that children experience³

PESQ-C is meant to be completed daily. Data from a 14-day period preceding the baseline visit and a 14-day period preceding the Week 16 visit are used to calculate the proportion of days or total time segments within a day (night, morning, afternoon, evening) with 1 or more EoE signs^2,3:

EoE, eosinophilic esophagitis; LSM, least squares mean; PESQ-C, Pediatric Eosinophilic Esophagitis Sign/Symptoms Questionnaire-Caregiver.

References:

1. Spergel JM, Chehade M, Ashok D, et al. Impact of dupilumab on caregiver-reported signs of EoE, using PESQ-C over 52 weeks: results from phase 3 EoE KIDS study. Poster presented: European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) 2025 Annual Meeting; May 14-17, 2025; Helsinki, Finland.
2. Chehade M, Dellon ES, Velpari S, et al. Dupilumab for eosinophilic esophagitis in patients 1 to 11 years of age. N Engl J Med. 2024;390:2239-2251. doi:10.1056/NEJMoa2312282
3. Kamat S, Yaworsky A, Guillemin I, et al. Novel questionnaires for assessing signs and symptoms of eosinophilic esophagitis in children. J Allergy Clin Immunol Pract. 2022;10(7):1856-1863.3. doi:10.1016/j jaip.2022.02.049

DUPIXENT DELIVERS RESULTS CAREGIVERS CAN SEE

DUPIXENT improved caregiver-reported EoE symptoms at Week 16, with continuous improvement through Week 52, as measured by PEESS v2.0

The PEESS v2.0-Caregiver version is a clinically validated, observer-reported outcomes measure that assesses the frequency and severity of EoE symptoms among pediatric patients. The PEESS v2.0-Caregiver version consists of 20 items and has a 1-month recall period. The total PEESS v2.0 score ranges from 0 to 100; higher scores indicate greater symptom burden among pediatric patients with EoE.3

^a Change in PEESS v2.0 score from baseline at Week 16: -19.86 with DUPIXENT (n=37) from a baseline of 38.0 vs -11.83 with placebo (n=34) from a baseline of 38

^b Change in PEESS v2.0 GERD/dysphagia/pain/nausea scores at Week 16: -26.34/-23.39/-22.41/-28.47 with DUPIXENT (n=37) vs - 9.67 /-16.28/-13.02/-16.45.

^c Change in PEESS v2.0 scores at Week 52 were not not measured as a clinical endpoint.

^d Change in PEESS v2.0 severity score at Week 52: -22.2 with DUPIXENT (n=32) from a baseline of 36.0.

^e Change in PEESS v2.0 GERD/dysphagia/pain/nausea scores at Week 52: -22.66/-26.76/-23.63/-19.34 with DUPIXENT (n=32).

^f Change in PEESS v2.0 total score at Week 100: -31.5 with DUPIXENT (n=23).

^g Change in PEESS v2.0 frequency/severity scores at Week 100: -33.8/-28.6 with DUPIXENT (n=23). h Change in PEESS v2.0 GERD/dysphagia/pain/nausea scores at Week 100: -25.27/-38.18/-31.52/-24.18 with DUPIXENT (n=23). i Change in PEESS v2.0 frequency score at Week 52: -25.1 with DUPIXENT (n=32) from a baseline of 44.7.

EoE, eosinophilic esophagitis; PEESS v2.0, Pediatric Eosinophilic Esophagitis Symptom Score version 2.0 (caregiver version).

PEESS v2.0-Caregiver is a questionnaire intended for use by patients aged 2 to 18 years to assess EoE symptoms that children experience^1,3

The PEESS v2.0-Caregiver version is a clinically validated, observer-reported outcomes measure that assesses the frequency and severity of EoE symptoms among pediatric patients. The questionnaire consists of 20 items and has a 1-month recall period. The total PEESS v2.0 score ranges from 0 to 100; higher scores indicate greater symptom burden among pediatric patients with EoE. The 4 major domains are listed below:

^aIncluding trouble swallowing, food getting stuck in the throat or chest, needing to drink to swallow food, eating less than others, and eating for longer than others.

References:

1. Ashok D, Rothenberg ME, Gold BD, et al. Dupilumab improves caregiver-reported eosinophilic esophagitis symptoms in children aged 1-11 years: 16-week results from the phase 3 EoE KIDS study. Poster 65 Meeting; November 5-8, 2025; Chicago, IL.
2. Oliva S, Gold BD, Parrish C, et al. Dupilumab maintains long-term symptomatic improvement in children with eosinophilic esophagitis, as reported by their caregivers: 100-week results from the open-label extension of the EoE KIDS study. Paper presented at: European Academy of Allergy and Clinical Immunology - Pediatric Allergy and Asthma Meeting (EAACI-PAAM) 2025;October 23-26, 2025; Palma de Mallorca, Spain.
3. Chehade M, Dellon ES, Velpari S, et al. Dupilumab for eosinophilic esophagitis in patients 1 to 11 years of age. N Engl J Med.
   2024;390:2239-2251. doi:10.1056/NEJMoa2312282

VISIBLE IMPROVEMENT IN ENDOSCOPIC SIGNS¹

DUPIXENT significantly improved endoscopic findings (EREFS) vs placebo at Week 16 with continued improvement through Week 52

CHILDREN MORE COMMONLY SHOW INFLAMMATORY SIGNS WITH EDEMA, EXUDATES, AND FURROWS ON ENDOSCOPY^3,c

^a EREFS change from baseline at Week 16 with DUPIXENT (n=37, baseline of 6.8): -3.5 vs placebo (n=34, baseline of 7.3): +0.3. LSM difference vs placebo: -3.8 (95% Cl: -4.9 to -2.6), P<0.001 (secondary endpoint).

^b EREFS change from baseline at Week 52 in patients who received DUPIXENT from baseline (n=37, baseline of 1.3): -4.8; in patients who switched from placebo to DUPIXENT at Week 16 (n=18, baseline of 73): -3.6.

^c There are other versions of EREFS, but this one was used for the LIBERTY TREET and EoE KIDS trials.

^d At Week 100, in patients who received DUPIXENT from Week 16 (n=22), change from baseline in EREFS score was -5.44.

DUPIXENT offered greater improvement in endoscopic signs (EREFS ≤2) vs placebo at Week 16 with continuous improvement through

Week 52

Proportion of patients with complete endoscopic remission (EREFS=0)^b

• 3% of patients with EREFS=0 with DUPIXENT (n=33) vs 0% with placebo (n=18) at Week 16 (Part A)
• 30% of patients with EREFS=0 with DUPIXENT from baseline (n=33) vs 13% with placebo/DUPIXENT (n=16) at Week 52 (Part B)
• -4 in 10 patients with EREFS=0 with DUPIXENT at Week 100 (Part C)

^a An EREFS total score ‹2 indicates endoscopic normalization.

^b At Week 52, 30.3% of patients with DUPIXENT since baseline (n=33) achieved EREFS=0, and 12.5% of placebo patients who switched to DUPIXENT at Week 16 (n=16); at Week 100, 38.9% of patients achieved EREFS=0 with DUPIXENT.

^c At Week 100, 100% of patients with DUPIXENT from baseline (n=18) achieved EREFS ≤2.

EREFS, Endoscopic Reference Score; LSM, least squares mean.

References:

1. Dellon ES, Gupta SK. A conceptual approach to understanding treatment response in eosinophilic esophagitis. Clin Gastroenterol Hepatol. 2019;17(11):2149-2160. doi:10.1016/j.cgh. 2019.01.030
2. Schroeder S, Menard-Katcher C, Schlag C, et al. Impact of dupilumab in pediatric patients with EoE over 52 weeks: endoscopic results from the phase 3 EoE KIDS study. Paper presented at: Societa Italiana di Gastroenterologia Epatologia e Nutrizione Pediatrica, (SIGENP) 2025; September 25-27, 2025; Rome, Italy.
3. Kia L, Hirano I. Advances in the endoscopic disease activity in eosinophilic esophagitis: 52-week results from the phase 3 LIBERTY EoE TREET study. Poster 15. Presented at: Society of Gastroenterology Nurses and Associates (SGNA) 52nd Annual Course; June 1-3, 2025; Pittsburgh, PA.
4. Chehade M, Dellon ES, Pesek RD, et al. Long-term dupilumab maintains histologic and endoscopic improvements in children with eosinophilic esophagitis (EoE): 100-Week results from the open-label extension (OLE) of the EoE KIDS study. Poster presented at:
   European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) 2025; May 14-17, 2025; Helsinki, Finland.
5. Schroeder S, Chehade M, Dellon ES, et al. Long-term dupilumab maintains improvements in esophageal features of esophagitis (EoE). Poster presented: 2025 American College of Gastroenterology (ACG) Annual Meeting; October 24-29, 2025; Phoenix, AZ.

VISIBLE IMPROVEMENT IN BOTH INFLAMMATORY AND FIBROSTENOTIC SUBSCORES

DUPIXENT significantly improved inflammatory and fibrostenotic EREFS subscores vs placebo at Week 16, with continuous improvement at Week 52^1,a-e

^a EREFS inflammatory subscore includes edema, exudates, and furrows. EREFS fibrostenotic subscore includes rings and strictures: a total score ‹2 indicates endoscopic normalization.

^b Mean percent change from baseline at Week 16 in EREFS inflammatory subscore with DUPIXENT (n=31): -54% vs +11.4% with placebo (n=27).

^c Mean percent change from baseline at Week 52 in EREFS inflammatory subscore in patients who received DUPIXENT since baseline (n=29): -69% and in patients who switched from placebo to DUPIXENT at Week 16 (n=13): -52%.

^d Mean percent change from baseline at Week 16 in EREFS fibrostenotic subscore with DUPIXENT (n=19): -9% vs - 6% with placebo (n=17).

^e Mean percent change from baseline at Week 52 in EREFS fibrostenotic subscore in patients who received DUPIXENT since baseline (n=13): -82% and in patients who switched from placebo to DUPIXENT at Week 16 (n=10): -57%.

^f Absolute change from baseline at Week 100 in EREFS inflammatory score in patients who received DUPIXENT from Week 52 to Week 100 (n=15): -2.87[n=34]).

^g Absolute change from baseline at Week 100 in EREFS fibrostenotic score in patients who received DUPIXENT from Week 52 to Week 100 (n=15): -0.40 (from -0.23 at Week 52 in patients who switched from placebo to DUPIXENT at Week 16 [n=15); and -0.40 in patients who received DUPIXENT since baseline [n=34]).

EREFS, Endoscopic Reference Score.

References:

1. Schroeder S, Menard-Katcher C, Schlag C, et al. Impact of dupilumab in pediatric patients with EoE over 52 weeks: endoscopic results from the phase 3 EoE KIDS study. Paper presented at: Societa Italiana di Gastroenterologia Epatologia e Nutrizione Pediatrica,(SIGENP) 2025; September 25-27, 2025; Rome, Italy.
2. Schroeder S, Chehade M, Dellon ES, et al. Long-term dupilumab maintains improvements in esophageal features of eosinophilic esophagitis (EoE). Poster presented: 2025 American College of Gastroenterology (ACG) Annual Meeting; October 24-29,2025;Phoenix, AZ.