Clinical Trial: The Chemopreventive Effect of Metformin in Patients With Familial Adenomatous Polyposis: Double Blinded Randomized Controlled Study

Study Status: Active, not recruiting
Recruit Status: Unknown status
Study Type: Interventional

Official Title:

Brief Summary: Familial adenomatous polyposis (FAP) leads to adenomas and eventual adenocarcinomas in colon and less frequently, duodenum. Chemopreventive strategies have been studied in FAP patients to delay the development of adenomas and cancers. The non-steroidal anti-inflammatory drugs (NSAIDs) and selective cyclooxygenase-2 inhibitor have shown the regression of colorectal and duodenal adenomas in FAP patients. However, these drugs showed gastrointestinal damage and cardiovascular risks, and new preventive strategies are needed. Metformin, a biguanide, which is widely used for treating diabetes mellitus, has recently been suggested to have a suppressive effect on tumorigenesis via mTOR-inhibiting pathway, and have no significant safety issues in long term use. The investigators devised a double-blind randomized controlled trial to evaluate the effect of metformin on polyps of colorectum and duodenum in non-diabetic FAP patients.

Detailed Summary:
Sponsor: Yonsei University

Current Primary Outcome: the mean percentage change of the number and size of polyps in colon and/or duodenum. [ Time Frame: After seven-month administration of metformin/placebo, colonoscopy/sigmoidoscopy and upper gastrointestinal endoscopy will be performed. ]

At the base-line endoscopy, India-ink tattoo will be placed in the ascending colon, sigmoid colon/rectum, and duodenum. In case of patient with retained rectum after colectomy and ileorectal anastomosis, sigmoidoscopy will be performed. The base-line and seven-month endoscopic examination will be recorded, and photographs will be taken at the tattoo-marked area and used for measurements of the number and size of polyps. The diameter of a polyp will be measured with the aid of biopsy forceps included in the photographic field, and only distinct polyps at least 2 mm in diameter will be counted.


Original Primary Outcome: the mean percentage change of the number and size of polyps in colon and/or duodenum. [ Time Frame: After six-month administration of metformin/placebo, colonoscopy/sigmoidoscopy and upper gastrointestinal endoscopy will be performed. ]

At the base-line endoscopy, India-ink tattoo will be placed in the ascending colon, sigmoid colon/rectum, and duodenum. In case of patient with retained rectum after colectomy and ileorectal anastomosis, sigmoidoscopy will be peformed. The base-line and six-month endoscopic examination will be recorded, and photographs will be taken at the tattoo-marked area and used for measurements of the number and size of polyps. The diameter of a polyp will be measured with the aid of biopsy forceps included in the photographic field, and only distinct polyps at least 2 mm in diameter will be counted.


Current Secondary Outcome:

Original Secondary Outcome:

Information By: Yonsei University

Dates:
Date Received: October 31, 2012
Date Started: November 2012
Date Completion: September 2015
Last Updated: July 8, 2013
Last Verified: July 2013