Celiac disease (CD) is an autoimmune disease of the small intestine caused by the consumption of gluten proteins from widely used food sources such as wheat, rye, and barley. Exposure of the small intestine to gluten causes an inflammatory response, leading to the destruction of intestine lining, often with severe symptoms including diarrhea, abdominal distention, fatigue, weight loss, anemia, and neurological symptoms. CD is a lifelong disease and the only treatment currently available is strict adherence to a life-time gluten free diet (GFD). However, adhering to this diet is difficult as gluten proteins are found in many food products. Therefore, the gluten-free diet has both lifestyle and financial implications for the individual and thus has been potential for impacting adversely on their quality of life.

Various approaches are being studied to reduce the need for careful control of the diet for those with CD, including the use of antibodies such as IgY. IgY is produced from the egg yolks of super immunized laying hens. Egg yolk antibodies are natural products with minimal toxicity, for those without egg allergy, and offer low-cost, hygienic production of study product. Once the IgY antibody is put into capsule form, it is called AGY.

Individuals with CD will be recruited only if they have a history of biopsy proven CD, currently follow a GFD but continue to have mild to moderate symptoms related to gluten exposure, and do not have an egg allergy. Blood will be tested for ATG antibody levels at screening. Those enrolled will have a 2 week run-in period where diet and symptoms are recorded, and will then receive AGY capsules to take with meals over a 4 week period. Outcomes will be measured by examining lab test results including antibody levels, symptoms, and quality of life.

The trial will last approximately 6 weeks. Individuals will be screened to ensure they are following a gluten free diet, continue to have mild to moderate symptoms of gluten exposure despite the diet, and have a history of biopsy proven celiac disease. Those meeting this criteria will then have a baseline visit which will include a short physical exam and additional lab work for safety measures, and quality of life questionnaires. They will record their diet and symptoms for 2 weeks, and then return to receive the study medication, which will be taken with all meals. The first dose will be taken in clinic to facilitate observation of any adverse effects. The next visit will be 2 weeks later for blood work and clinic visit, and then again 2 weeks later for the final visit. Participants will be prompted to report any adverse events that occur during the trial period and at the completion of the trial. During the trial period, the study coordinator will phone participants to remind them to complete their questionnaires and to inquire about adverse events. All participants will receive AGY capsules (500 mg per capsule), and will take 2 capsules with each meal.

Outcome measures The primary outcome variable will be the safety (adverse events, lab results, symptoms), which will be measured throughout the study.

The secondary outcome will be ATG antibody levels, which will be measured at each visit.

Inclusion Criteria:

• age 18 or over
• confirmed diagnosis of Celiac disease by previous biopsy
• follow a gluten-free diet (GFD)
• have mild to moderate symptoms despite the GFD diet

Exclusion Criteria:

• diabetic
• use of steroids in previous year
• current use of ASA/NSAIDs, metronidazole, or misoprostol
• excess alcohol intake
• egg allergy
• history of severe complications of celiac disease or chronic active GI disease
• pregnancy