Effect of addition of elemental nutrition to an elimination diet on esophageal inflammation in adult eosinophilic
esophagitis (EoE) patients: A randomized controlled trial

Rationale: There is sufficient evidence to state that food allergy plays an important role in eosinophilic esophagitis (EoE), and dietary treatment has proven efficacy in these patients. Elimination diets and elemental nutrition with amino acid-based formula are effective but both also have limitations. Combination of elimination diets with amino acid-based nutrition might improve adherence, prevent weight loss and increase the feasibility of the elimination diet. Furthermore, there is data suggesting that amino acid-based nutrition has anti-inflammatory effects itself, aside from the removal of all disease triggering food allergens. We hypothesize that the addition of amino acid-based nutrition to a four food elimination diet (FFED) is more effective than a FFED alone due to the: (1) anti-inflammatory effect of the amino acids and (2) increased feasibility of allergen avoidance.

Objectives: Primary: To evaluate whether, in adult EoE patients, the addition of an elemental (amino acid-based) nutrition to the FFED is more effective in decreasing the esophageal eosinophilic inflammation and increasing the dietary acceptability and patients’ adherence than a FFED alone.

Study design: Prospective randomized controlled trial

Study population: Adult EoE patients with proven active disease (>15 eosinophils per high power field (HPF))

Intervention: EoE patients are treated with a FFED alone or with a FFED with addition of amino acid-based nutrition for 6 weeks. Baseline upper endoscopy is performed and esophageal biopsies are taken for histological and transcriptional analyses before and after 6 weeks diet. Diet acceptability and adherence, symptoms and quality of life are being investigated using questionnaires. Body Mass Index (BMI) is calculated and all measurements are repeated after 6 weeks of dietary treatment.

Main study parameters/endpoints: Reduction of esophageal eosinophilic inflammation with FFED compared with FFED with addition of elemental (amino acid-based) nutrition. Secondary endpoints are acceptability of the treatment, quality of life and symptoms.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Following an elimination diet can be a burden for adults. The risk of the performed procedures consists of the very small risk of biopsies, namely bleeding and perforation. The study will evaluate the effectiveness of a new dietary approach in EoE and contribute to better understanding of this condition.

To evaluate whether the addition of amino-acid based nutrition to FFED is superior to FFED
alone in terms of improvement of the esophageal eosinophilic inflammation, and improved patients’ adherence and acceptability of the diet. Secondary, it will be important to study the effect of additional amino acid-based nutrition on symptoms as measured by
patient reported outcomes, weight loss prevention and quality of life. In both arms the efficacy of the intervention will be controlled
for the total composition of the diet.

12 months

FFED v.s. FFES with addition of elemental nutrition