Sirolimus and Familial Adenomatous Polyposis (FAP)

Inclusion Criteria: * ≥ 18 years * A genetically confirmed APC mutation * Classical FAP phenotype (100-1000 colorectal adenomatous polyps) * Subtotal colectomy with ileorectal anastomosis (IRA) or total colectomy with ileo-anal pouch anastomosis (IPAA) * Severe rectal or pouch polyposis, defined as having \>25 polyps amenable to complete removal (InSiGHT 2011 Staging System score of 3) * Fertile patients must use effective contraception during study treatment and until 12 weeks after study treatment Exclusion Criteria: * Inability to give informed consent * Participation in another interventional clinical trial * Subjects who are pregnant or breast-feeding, proved with a negative pregnancy test if female of child-bearing potential * Prior pelvic irradiation * Invasive malignancy in the past 5 years * Subjects who are HIV positive * Subjects with severe systemic infections, current or within 2 weeks prior to study start * Subjects with known severe restrictive or obstructive pulmonary disorders * Known sucrase insufficiency, isomaltase insufficiency, fructose intolerance, glucose malabsorption, galactose malabsorption, galactose intolerance or Lapp-lactase deficiency * History of pulmonary embolism or deep venous thrombosis * Major surgery less than or equal to 2 weeks prior to enrollment or any planned surgery within treatment period * Active post-operative complication, e.g. infection, delayed wound healing * History of hypersensitivity to sirolimus or to drugs of similar…