Clinical Research Directory

Inclusion Criteria: 1. Participant must be ≥18 years of age inclusive. 2. Participant must have documented FAP, confirmed by adenomatous polyposis coli genotype mutation testing. 3. Participant must have at least 1 of the following high-risk features: \>100 polyps but ≤500 polyps in the colon, or ≥10 polyps in the retained rectum/sigmoid or ileal pouch (≥3 mm in size), or Spigelman stage 3 or 4 with at least 1 polyp ≥10 mm to be removed at baseline or on endoscopy performed within 18 months of screening. 4. Contraceptive use by participants or participant partners until at at least 12 weeks after stopping study treatment. 5. Agree not to donate gametes for the purpose of reproduction until at at least 12 weeks after stopping study treatment. 6. Willing to undergo endoscopic evaluation. Exclusion Criteria: 1. Participant has unresected or incompletely resected high-grade dysplasia or cancer within the duodenum, colon, rectum, or ileal pouch at screening endoscopy. 2. Participant has any polyps ≥8 mm in the duodenum, colon, rectum, or ileal pouch remaining after screening endoscopy (polyps ≥8 mm are to be resected during screening endoscopy). 3. Participant has had surgery within 6 weeks of the trial. 4. Participant has active malignancy or history of malignancy diagnosed within 24 months of first dose of trial intervention. 5. Participant has a history of, or currently has, an acquired or primary (congenital) immunodeficiency. 6. Participant has active and clinically significant tuberculosis (positive Quantiferon Gold test), bacterial, fungal, or viral infection, including human immunodeficiency virus (HIV). 7. Participant has any medical or social condition that, in the opinion of the Investigator, might increase participant risk if enrolled, prevent participant compliance to trial procedures, or present an unacceptable confound to safety or clinical trial data.