Ignite Creation Date:
2024-05-05 @ 11:52 AM
Last Modification Date:
2024-10-26 @ 9:15 AM
Study NCT ID:
NCT00153816
Status:
COMPLETED
Last Update Posted:
2017-03-15
First Post:
2005-09-07
Brief Title:
Vitamin DCalcium Polyp Prevention Study
Sponsor:
Dartmouth-Hitchcock Medical Center
Organization:
Dartmouth-Hitchcock Medical Center
Study Overview
Official Title:
Vitamin DCalcium Polyp Prevention Study
Status:
COMPLETED
Status Verified Date:
2017-02
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
Extensive experimental and observational data suggest that intake of calcium and of vitamin D exert protective effects on colorectal neoplasia Building on their previous work the investigators will investigate the chemopreventive effect of vitamin D in the large bowel to study whether calcium with vitamin D is more effective than calcium alone and to confirm their positive finding regarding calcium The goal of this study is the development of chemopreventive combinations that will reduce risk of colorectal neoplasia sufficiently to permit the lengthening of surveillance intervals in most patients and to clarify important issues regarding the mechanisms of colorectal carcinogenesis and chemoprevention
Detailed Description:
This study is a double-blind placebo-controlled trial of vitamin D andor calcium supplementation for the prevention of large bowel adenomas Subjects will be recruited from 11 Study Centers in North America Eligible subjects will have had at least one large bowel adenoma removed in the 4 months prior to study entry and no remaining polyps in the bowel after complete colonoscopic examination Participants will be randomized in a partial 2 x 2 factorial design to vitamin D 1000 IUday calcium carbonate 1200 mg elemental calciumday both agents or placebo only Full Factorial randomization Women who decline to forego calcium supplementation will be randomized only to calcium alone or to calcium plus vitamin D Two Arm randomization Randomization will be stratified by gender study center of recruitment and anticipated follow-up interval see below and will be conducted separately for female subjects randomized only to vitamin D We anticipate enrolling up to 3000 participants to reach a total of up to 2400 randomized subjects As safety measures blood levels of calcium creatinine and 25-OH-vitamin D will be obtained at baseline and 1 year after randomization as well as 3 years after randomization for subjects with a 5-year surveillance cycle Every six months after randomization subjects will complete a questionnaire regarding compliance with study agents use of medications and vitaminmineral supplements illnesses hospitalizations and dietary intake of calcium and vitamin D The primary endpoint of the study will be new adenomas detected on follow-up colonoscopy These examinations are scheduled to occur either 3 years or 5 years after the qualifying examination depending on the follow-up interval recommended by each patients endoscopist Some patients may for medical reasons have a colonoscopy at a time other than 3 or 5 years after the qualifying examination Information from these exams will be included in analyses where appropriate In the primary analyses the occurrence of new adenomas in the interval between randomization and the follow-up exam will be compared between subjects randomized to vitamin D with or without calcium versus those randomized to no vitamin D with or without calcium between subjects randomized to calcium with or without vitamin D versus those randomized to no calcium with or without vitamin D excluding women electing to receive calcium who therefore cannot participate in the calcium component of the study and between those randomized to calcium plus vitamin D versus those randomized to calcium alone In secondary analyses we will examine the impact of baseline vitamin D levels and vitamin D receptor VDR polymorphisms on the vitamin D effects Effects on advanced adenomas will also be assessed as a secondary outcome Participants will be invited to participate in an optional Observational Follow Up phase of the study that will begin following the end of treatment In this phase of the study subjects will continue to be followed on an observational basis no study treatment with annual questionnaires until the time of a subsequent colonoscopy that is at least three years from the follow up colonoscopy at which study treatment was ended We will examine the occurrence of new adenomas in the interval between the colonoscopy exam at the end of study treatment and the exam at the end of observational follow up period
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 5R01CA098286-10 | NIH | None | httpsreporternihgovquickSearch5R01CA098286-10 |