Vitamin D/Calcium Polyp Prevention Study
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ClinicalTrials.gov Identifier: NCT00153816 |
Recruitment Status :
Completed
First Posted : September 12, 2005
Results First Posted : October 20, 2015
Last Update Posted : March 15, 2017
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Colorectal Cancer Polyps Adenomas | Drug: Calcium Carbonate Drug: Vitamin D3 Drug: placebo | Phase 2 Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 2813 participants |
Allocation: | Randomized |
Intervention Model: | Factorial Assignment |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Primary Purpose: | Prevention |
Official Title: | Vitamin D/Calcium Polyp Prevention Study |
Actual Study Start Date : | July 2004 |
Actual Primary Completion Date : | October 2013 |
Actual Study Completion Date : | June 2016 |

Arm | Intervention/treatment |
---|---|
Experimental: Full Factorial Placebo
subjects in 2X2 factorial design; randomized to daily placebo
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Drug: placebo
placebo; two tablets per day |
Experimental: Full Factorial Calcium
subjects in 2X2 factorial design; randomized to daily 1200 mg as calcium carbonate
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Drug: Calcium Carbonate
3 gm/daily; 1200 mg elemental calcium/daily; two tablets per day; 600 mg elemental calcium/tablet |
Experimental: Full Factorial Vitamin D
Subjects in 2X2 factorial design; randomized to daily 1000 IU vitamin D3
|
Drug: Vitamin D3
1000 IU/daily; two tablets per day; 500 IU per tablet |
Experimental: Full Factorial Calcium Plus Vitamin D
Subjects in 2X2 factorial design; randomized to daily 1200 mg as calcium carbonate and 1000 IU vitamin D3
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Drug: Calcium Carbonate
3 gm/daily; 1200 mg elemental calcium/daily; two tablets per day; 600 mg elemental calcium/tablet Drug: Vitamin D3 1000 IU/daily; two tablets per day; 500 IU per tablet |
Experimental: Two Arm Placebo
Women choosing to take daily 1200 mg as calcium carbonate randomized to daily placebo
|
Drug: Calcium Carbonate
3 gm/daily; 1200 mg elemental calcium/daily; two tablets per day; 600 mg elemental calcium/tablet |
Experimental: Two Arm Vitamin D
Women choosing to take daily 1200 mg as calcium carbonate randomized to daily 1000 IU vitamin D3
|
Drug: Calcium Carbonate
3 gm/daily; 1200 mg elemental calcium/daily; two tablets per day; 600 mg elemental calcium/tablet Drug: Vitamin D3 1000 IU/daily; two tablets per day; 500 IU per tablet |
- Colorectal Adenomas [ Time Frame: 1 to 10 years ]
- Advanced Colorectal Lesions [ Time Frame: 1 to 10 years ]Includes: adenomas >=1 cm, adenomas with high grade dysplasia, adenomas with villous features, or cancer.

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 45 Years to 75 Years (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- One or more histologically verified neoplastic polyp (adenoma) that is at least 2 mm in size removed from the large bowel with the entire large bowel examined by colonoscopy and documented to be free of further polyps or areas suspicious for neoplasia within 120 days of study entry
- Anticipated colonoscopic follow-up three years or five years after the qualifying colonoscopy
- Age between 45 and 75 years at enrollment
- (Women)Agreement to avoid pregnancy (i.e., use of standard contraception)
- Willingness to forego calcium supplementation (including multivitamins containing calcium) or, for women only, option of taking calcium supplementation of 1200 mg/daily (contained in the study pills)
- Willingness to forego vitamin D supplementation (including multivitamins containing vitamin D)
- Agreement to daily dietary intake of the equivalent of not more than 1200 mg calcium
- Agreement to daily dietary intake of the equivalent of not more than 400 IU vitamin D
- Blood calcium level within normal range
- Blood creatinine level not to exceed 20% above upper limit of normal
- Serum 25-(OH)-vitamin D within lower limit of normal to 70 ng/ml
- Ability and willingness to follow the study protocol, as indicated by provision of informed consent to participate
- Good general health, with no severely debilitating diseases or active malignancy that might compromise the patient's ability to complete the study
Exclusion Criteria:
General exclusionary criteria:
- Participation in another colorectal (bowel) study (intervention study) in the past 5 years
- Current participation in any other clinical trial (intervention study)
- Pregnancy or lactation
- A diagnosis of narcotic or alcohol dependence in the past 5 years
- A diagnosis of dementia (e.g. Alzheimer's) in the past 5 years
- A diagnosis of a significant psychiatric disability (e.g. Schizophrenia, refractory bipolar disorder, current severe depression) in the past 5 years
Exclusions due to derangement of calcium metabolism or indications /contraindications to study agents:
- Any diagnosis of kidney stones
- A diagnosis of granulomatous diseases, e.g. sarcoidosis, active chronic fungal or mycobacterial infections (tuberculosis, histoplasmosis, coccidioidomycosis, blastomycosis), berylliosis, Wegener's granulomatosis in the past 5 years
- A diagnosis of hyperparathyroidism or other serious disturbance of calcium metabolism in the past 5 years
- A diagnosis of severe kidney disease, e.g. chronic renal failure in the past 5 years
- A diagnosis of unexplained hypercalcemia in the past 5 years
- Any Diagnosis of osteoporosis with physician recommendation for treatment of low bone mass
- A diagnosis of two or more low trauma fractures in the past 5 years
- A diagnosis of a medical condition requiring treatment with vitamin D (e.g. osteomalacia) in the past 5 years
Exclusions due to intestinal or bowel problems:
- Any diagnosis of invasive carcinoma of the large bowel (even if confined to a polyp)
- Any diagnosis of familial colorectal cancer syndromes, e.g. Familial Adenomatous Polyposis (FAP) (including Gardner syndrome, Turcot's syndrome), Hereditary Nonpolyposis Colorectal Cancer (HNPCC), Hamartomatous Polyposis syndromes (including Peutz-Jeghers or Familial Juvenile Polyposis)
- Any diagnosis of inflammatory bowel disease, e.g. Crohn's Disease, Ulcerative Colitis
- A diagnosis of chronic intestinal malabsorption syndromes, e.g. celiac sprue, bacterial overgrowth, chronic pancreatitis, pancreatic insufficiency in the past 5 years
- Any large bowel resection
Exclusions due to poor health:
- A diagnosis of malignancy, other than non-melanoma skin cancer in the past 5 years
- A diagnosis of severe lung disease - class 3 or 4 (e.g. chronic obstructive pulmonary disease or emphysema requiring oxygen) in the past 5 years
- A diagnosis of severe heart disease: cardiovascular disease functional class 3 or 4 in the past 5 years
- Any diagnosis of severe liver disease, e.g. cirrhosis
Exclusions due to shipping regulations:
- Any current/past HIV positive diagnosis
- Active hepatitis B, defined as : Hep B surface antigen positive
- Active hepatitis C, defined as : measurable hepatitis C RNA
Drug exclusions:
- Use of chronic oral corticosteroid therapy in the past 5 years
- Use of lithium in the past 5 years
- Use of phenytoin's in the past 5 years
- Use of quinidine in the past 5 years
- Use of therapeutic vitamin D in the past 5 years

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): NCT00153816
United States, California | |
University of Southern California | |
Los Angeles, California, United States, 90089 | |
United States, Colorado | |
University of Colorado | |
Denver, Colorado, United States, 80220 | |
United States, Georgia | |
Emory University | |
Atlanta, Georgia, United States, 30322 | |
United States, Iowa | |
University of Iowa | |
Iowa City, Iowa, United States, 52242 | |
United States, Minnesota | |
University of Minnesota | |
Minneapolis, Minnesota, United States, 55455 | |
United States, New Hampshire | |
Dartmouth Hitchcock Medical Center | |
Lebanon, New Hampshire, United States, 03766 | |
United States, North Carolina | |
University of North Carolina | |
Chapel Hill, North Carolina, United States, 27599 | |
United States, Ohio | |
Cleveland Clinic Foundation | |
Cleveland, Ohio, United States, 44195 | |
United States, South Carolina | |
University of South Carolina | |
Columbia, South Carolina, United States, 29203 | |
United States, Texas | |
University of Texas | |
Houston, Texas, United States, 77030 | |
Puerto Rico | |
University of Puerto Rico | |
San Juan, Puerto Rico |
Principal Investigator: | John A. Baron, MD | Dartmouth-Hitchcock Medical Center |
Responsible Party: | Dartmouth-Hitchcock Medical Center |
ClinicalTrials.gov Identifier: | NCT00153816 |
Other Study ID Numbers: |
5R01CA098286-03 ( U.S. NIH Grant/Contract ) 5R01CA098286-10 ( U.S. NIH Grant/Contract ) |
First Posted: | September 12, 2005 Key Record Dates |
Results First Posted: | October 20, 2015 |
Last Update Posted: | March 15, 2017 |
Last Verified: | February 2017 |
Colorectal neoplasms Adenomatous polyps |
Adenoma Polyps Neoplasms Pathological Conditions, Anatomical Neoplasms, Glandular and Epithelial Neoplasms by Histologic Type Vitamin D Cholecalciferol Calcium Carbonate |
Calcium Vitamins Micronutrients Physiological Effects of Drugs Calcium-Regulating Hormones and Agents Bone Density Conservation Agents Antacids Molecular Mechanisms of Pharmacological Action Gastrointestinal Agents |