Phase 3 Trial of eRapa in Patients With Familial Adenomatous Polyposis

The main goal of this clinical trial is to learn if the drug eRapa works to slow down the progression of disease in patients diagnosed with Familial Adenomatous Polyposis (FAP). Researchers will compare eRapa to Placebo. The questions to be answered by this trial are: * Does taking eRapa help to slow down the progression of the disease in patients with FAP? * Is eRapa a safe treatment for patients diagnosed with FAP? * What is the effect of eRapa on the number of polyps found in GI tract of patients diagnosed with FAP? * How does treatment with eRapa affect a patient's quality of life? Participants will: * Take eRapa or placebo once per day every other week until disease progresses (gets worse), stops taking part in the trial or dies. * Visit the clinic once every 3 months for check ups and tests. * Have an endoscopy at the start of the trial and then every 6 months to check on whether the disease is getting better or worse.