Title
Phase 2 Study to Evaluate the Efficacy and Safety of TPST-1495 in Patients with Familial Adenomatous Polyposis (FAP)

Description
This open-label phase II trial tests how well TPST-1495 works in reducing the number of polyps in the small bowel and colon in patients with familial adenomatous polyposis (FAP). FAP is an inherited condition in which numerous polyps (growths that protrude from mucous membranes) form on the inside walls of the colon and rectum. It increases the risk for colon cancer. TPST-1495 binds to specific prostaglandin receptors. TPST-1495 is a dual antagonist of the prostaglandin E2 (PGE2) receptor subtypes EP2 and EP4, while sparing the immune-stimulating EP1 and EP3 receptors. TPST-1495 may help reduce the number of polyps in the small bowel and colon in patients with FAP.

Objective
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.

Treatment 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.

Key Eligibility For full eligibility, see this study's ClinicalTrials.gov record

Applicable Disease Sites
Colon and Rectum; Gastrointestinal cancers, other

Participating Institutions
UW Health Eastpark Medical Center; UW Health University Hospital