A Double-Blind, Placebo-Controlled, Randomized Study Of Combination Vitamin E, Selenium And Soy Protein Product In Subjects With High Grade Prostatic Intraepithelial Neoplasia
- Determine whether nutritional supplementation with soy protein isolate, vitamin E, and
selenium can delay the time to development of invasive prostate cancer (disease-free
survival) in patients with high-grade prostatic intraepithelial neoplasia.
- Determine the effect of this supplementation on intermediate endpoints that may reflect
a lessened risk of invasive prostate cancer (e.g., serum PSA levels, hormone levels,
lycopene, malondialdehyde, vitamin E, and reduced thiol groups) in these patients.
- Determine the safety of this supplementation in these patients.
OUTLINE: This is a randomized, double-blind, multicenter study. Patients are stratified
according to participating center. Patients are randomized to 1 of 2 treatment arms.
- Arm I: Patients receive oral vitamin E, oral selenium, and oral soy protein isolate
- Arm II: Patients receive oral placebo twice daily. In both arms, treatment continues
for 3 years in the absence of invasive prostate cancer (demonstrated on biopsy) or
Patients are followed every 3 months for 1 year and then every 6 months for 2 years.
PROJECTED ACCRUAL: A total of 306 patients (153 per treatment arm) will be accrued for this
study within 6 years.
Allocation: Randomized, Masking: Double-Blind, Primary Purpose: Prevention
Princess Margaret Hospital, Canada
United States: Federal Government