Folic Acid in Preventing Colorectal Polyps in Patients With Previous Colorectal Polyps
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|ClinicalTrials.gov Identifier: NCT00512850|
Recruitment Status : Completed
First Posted : August 8, 2007
Last Update Posted : March 3, 2017
RATIONALE: Chemoprevention is the use of certain substances to keep cancer from forming. The use of folic acid may prevent colorectal cancer.
PURPOSE: This randomized clinical trial is studying how well folic acid works compared with a placebo in preventing colorectal polyps in patients who have had previous colorectal polyps.
|Condition or disease||Intervention/treatment||Phase|
|Adenoma of Large Intestine||Dietary Supplement: Folic acid Other: Placebo||Not Applicable|
- Determine if folic acid supplementation lowers the adenoma recurrence rate.
- Determine the number of adenomas per patient and the size and histology of the adenoma.
- Assess the interaction between folic acid and alcohol, methionine, and aspirin intake.
- Assess the interaction between folic acid and pretrial and midtrial folate levels.
- Assess other complementary biomarkers such as DNA methylation and blood folate level as risk factors for polyp recurrence.
OUTLINE: Patients are randomized to 1 of 2 treatment arms.
- Arm I: Patients receive oral folic acid once daily.
- Arm II: Patients receive oral placebo once daily. At least 1 year after beginning treatment, patients are sent a blood collection kit in order to measure plasma vitamin B12 levels, to measure folate to assess compliance.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||672 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||Double (Participant, Investigator)|
|Official Title:||The Nurses' Health Study (NHS) and Health Professionals Follow-Up Study (HPFS) Folic Acid Prevention Trial|
|Study Start Date :||May 1996|
|Actual Primary Completion Date :||March 2004|
|Actual Study Completion Date :||February 1, 2017|
Folic acid supplement 1g/day
Dietary Supplement: Folic acid
Intervention group 1g folic acid per day
Placebo pill once per day
One placebo pill per day
- Recurrent colorectal adenoma [ Time Frame: May 1996-March 2004 ]
- recurrent adenoma by location, size, stage, number, [ Time Frame: May1996-March 2004 ]
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00512850
|Principal Investigator:||Edward L. Giovannucci, MD, ScD||Dana-Farber/Brigham and Women's Cancer Center|