Phase III Study of the Effects of Selenium on Adenomatous Polyp Recurrence
- Compare the effects of selenium vs placebo on the recurrence of adenomatous colorectal
polyps, in terms of histologic type, degree of dysplasia, number, size, and location,
in patients with adenomatous colorectal polyps.
- Compare the type, incidence, and outcome of side effects in patients treated with these
- Determine patient adherence to long-term treatment with these regimens.
- Determine the effects of regimen modification by baseline blood selenium level,
low-dose aspirin, selenoprotein genetic marker polymorphisms (e.g., GPx-1, GPx-2, and
- Determine the effects of low-dose aspirin (81 mg/day) modification by ornithine
decarboxylase promoter genotype, and toxicity by slow-metabolizer genotypes of the
cytochrome p450 2C9 and UT1A6 loci in these patients.
OUTLINE: This is a randomized, double-blind, placebo-controlled, multicenter study. Patients
are stratified according to use of low-dose (≤ 81 mg/day) aspirin (yes vs no). Patients are
randomized to 1 of 2 treatment arms.
- Arm I: Patients receive oral selenium once daily.
- Arm II: Patients receive oral placebo once daily. In both arms, treatment continues for
up to 5 years* in the absence of disease progression or unacceptable toxicity.
Patients undergo follow-up colonoscopy approximately 5 years* after baseline colonoscopy.
NOTE: Some patients will continue participation for up to 7 and a half years
PROJECTED ACCRUAL: A total of 1,600 patients with an adenoma will be randomized to this
study, followed by a second group of randomization of 200 patients with at least one
advanced adenoma (at baseline) for a substudy. Total planned randomizations = 1,800
Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Prevention
Recurrence of colorectal adenomatous polyps in relation to histologic type, degree of dysplasia, number, size, and location.
Surveillance colonoscopy is recommended 3 to 5 years after removal of colorectal adenoma(s). Participants will remain on the study intervention until their surveillance colonoscopy and recurrence will be assessed per measurements above. Surveillance colonoscopy is determined by participants GI physician.
3 to 5 years after baseline colonoscopy
M. Peter Lance, MD
University of Arizona
United States: Food and Drug Administration
|Mayo Clinic Scottsdale||Scottsdale, Arizona 85259|
|Virginia G. Piper Cancer Center at Scottsdale Healthcare - Shea||Scottsdale, Arizona 85260|
|University of Colorado Cancer Center at UC Health Sciences Center||Aurora, Colorado 80045|
|Baylor University Medical Center - Dallas||Dallas, Texas 75246|
|Veterans Affairs Medical Center - Phoenix||Phoenix, Arizona 85012|
|Arizona Cancer Center - Tucson Clinic||Tucson, Arizona 85724-5024|
|Endoscopy Center of Western New York||Williamsville, New York 14221|