Tryptophan for Impaired AhR Signaling in Celiac Disease
Recruiting now NCT05576038
Run by McMaster University · for 18 to 75 · All sexes
What this study is about
This is a prospective, randomized, double-blind, placebo-controlled exploratory trial to evaluate the effect of L-tryptophan supplementation on celiac-related symptoms in individuals who have biopsy-confirmed celiac disease (CeD) and symptoms non-responsive to a gluten-free diet (GFD). Fifty participants, aged 18 to 75 years, who self-report persistent CeD-related symptoms despite taking a GFD for more than 1 year and who score \> 40 on the Celiac Symptom Index (CSI) will be randomized to receive L-tryptophan or placebo for 3 weeks.
Who can join (things the study team will check)
✅ You may be able to join if…
- 18 and 75 years of age
- Celiac disease (CeD) diagnosis: Individuals with histological and serological evidence of CeD serology (positive biopsy and anti-tTG IgA)
- Persistent CeD related symptoms (>40 on the Celiac Symptom Index) despite >1 year of a gluten free diet (GFD)
🚫 You may not be able to join if…
- Acid anti-secretory and antacid medications
- Antibiotics, antibacterial agents or probiotics, currently, or within the last 8 weeks
- Current organic gastrointestinal or other autoimmune diseases, such as inflammatory bowel disease or diabetes mellitus (type 1)
- Lactose and/or fructose intolerance
- History of bariatric surgery, fundoplication or gastrectomy (partial or complete)
- Connective tissue disease
- Concurrent organic GI pathology other than benign polyps, haemorrhoids, lipomas, Helicobacter pylori infection, diverticulosis and melanosis coli
- Chronic treatment with high dose opioids
- Alcohol or drug abuse
- Concurrent systemic disease and/or laboratory abnormalities considered by investigators to be a risk or that could interfere with data collection
- Allergy or sensitivity to any component of the study medication or placebo
- Use of lithium and monoamine oxidase inhibitors (MAOIs)
- Participation in another dietary treatment study within the last 4 weeks
Where this trial is running
- McMaster University, Hamilton, Ontario, Canada
Who to contact
Gaston H Rueda, MD · 905 521-2100 · ruedag@mcmaster.ca
It's completely normal to call and ask questions before deciding anything. Mention the study ID: NCT05576038.
Verify everything on the official ClinicalTrials.gov record. Page updated July 2026.