• Participants must be 18 to 75 years of age inclusive, at the time of signing the informed consent.

• Participants with physician-diagnosed celiac disease with documented history of biopsy-proven celiac disease confirmed by medical records or physician statement.

• Participants who have self-reported attempt to maintain a GFD (and confirmed via questionnaire) for at least 12 consecutive months and must be willing to maintain their current diet for the duration of study participation.

• Participants have an adequate comprehension of a GFD as assessed by the Investigator.

• Participants willing to undergo all assessments in the protocol, including 2 esophagogastroduodenoscopies with duodenal biopsies.

• Participants who completed CDSD with ≥ 75% compliance from screening until randomization.

• During screening, participants must have at least one gastrointestinal symptom (i.e., diarrhea, abdominal pain, bloating, or nausea) of moderate or greater severity, as measured by the CDSD Gastrointestinal Domain, on at least 3 days out of any consecutive 7-day period considered by the investigator to be related to gluten exposure (i.e., due to celiac disease). The symptom can vary, but severity must be moderate or greater on three or more days. Participants must meet symptom criteria to undergo baseline esophagogastroduodenoscopy (EGD).