An Investigational Drug (TPST-1495) in Patients With Familial Adenomatous Polyposis

PRIMARY OBJECTIVES: I. To assess the activity of TPST-1495 in reducing duodenal polyp burden in patients with FAP. II. To assess the safety of TPST-1495 in patients with FAP; we will evaluate the incidence of grade 2 or 3 adverse events. SECONDARY OBJECTIVE: I. The activity of TPST-1495 in reducing rectum/IPAA (ileal pouch-anal anastomosis) polyp burden in patients with FAP. EXPLORATORY OBJECTIVES: I. Reduction in intestinal polyp burden as a function of immunohistochemical staining at baseline and end of intervention (6-months) of rectal and duodenal tissue samples for COX-2 expression level, beta-catenin, and Ki-67. II. Proteomic profile of serum correlated to clinical response to therapy compared between baseline and end of intervention. III. Biospecimen acquisition. OUTLINE: Patients receive TPST-1495 orally (PO) once daily (QD) for 6 months in the absence of unacceptable toxicity. Patients also undergo esophagogastroduodenoscopy (EGD) and gastrointestinal (GI) endoscopy with biopsy at baseline and end of treatment and undergo blood sample collection throughout the study. After completion of study treatment, patients are followed up at 1 month.