Dupilumab is a human monoclonal antibody inhibiting IL-4 and IL-13. Part A of the LIBERTY EoE TREET trial (NCT03633617) demonstrated that 300 mg dupilumab (subcutaneous injection, once weekly) was more efficacious than placebo after 24 weeks in a symptomatic, severely inflamed population of EoE patients. Part C of the trial investigated the long-term efficacy and safety of dupilumab in a 28-week extended treatment period1.
All patients (n=77) who completed part A were enrolled in part C and received 300 mg dupilumab (subcutaneous injection, once weekly). Co-primary endpoints were the absolute change in Dysphagia Symptom Questionnaire (DSQ) score and the proportion of patients achieving peak oesophageal intraepithelial eosinophil count of ≤6 eosinophils/high-power field at week 52. The findings were presented by Dr Evan Dellon (University of North Carolina, NC, USA).
After 52 weeks, the reductions in DSQ scores were maintained for patients who were randomised to the dupilumab condition in part A of the trial (LS mean: -21.9 at 24 weeks; -23.4 at 52 weeks). Patients who were originally randomised to placebo showed similar changes in DSQ score at 52 weeks (LS mean: -9.6 at 24 weeks; -21.7 at 52 weeks). The intraepithelial eosinophil counts showed a comparable pattern: the proportion of patients that achieved an eosinophil count of ≤6 eosinophils/high-power field in the dupilumab arm in part A of the trial was maintained throughout part C (percentage of responders: 59.5% at 24 weeks; 55.9% at 52 weeks).
Original placebo receivers showed similar response rates after 52 weeks (percentage of responders: 5.1% at 24 weeks; 60.0% at 52 weeks). Treatment-emergent adverse events (AEs) were mostly mild, injection-site reactions and injection-site erythema being the most common. Two treatment-emergent AEs led to discontinuation of the study.