Zinc Supplements in Lowering Cadmium Levels in Smokers

This study is ongoing, but not recruiting participants.
Sponsor:
Collaborator:
Information provided by (Responsible Party):
Comprehensive Cancer Center of Wake Forest University
ClinicalTrials.gov Identifier:
NCT00376987
First received: September 13, 2006
Last updated: July 10, 2013
Last verified: July 2013

September 13, 2006
July 10, 2013
December 2003
October 2006   (final data collection date for primary outcome measure)
  • Reduction of cadmium levels [ Time Frame: 17 weeks ] [ Designated as safety issue: No ]
  • Serum levels of cotinine, zinc, and cadmium at 3 pre-supplementation visits and at 6 supplementation visits [ Time Frame: 17 weeks ] [ Designated as safety issue: No ]
  • Correlation of increased cadmium levels with decreased mismatch repair [ Time Frame: 17 weeks ] [ Designated as safety issue: No ]
  • Reversal of cadmium-induced inhibition of mismatch repair [ Time Frame: 17 weeks ] [ Designated as safety issue: No ]
Not Provided
Complete list of historical versions of study NCT00376987 on ClinicalTrials.gov Archive Site
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Zinc Supplements in Lowering Cadmium Levels in Smokers
Do Dietary Supplements of Zinc Reduce Serum Cadmium Levels in Smokers?

RATIONALE: Zinc supplements may lower cadmium levels in smokers and may help prevent DNA damage.

PURPOSE: This clinical trial is studying how well zinc supplements work in lowering cadmium levels in smokers.

OBJECTIVES:

  • Determine whether zinc supplements reduce cadmium levels in smokers.
  • Measure serum levels of cotinine (a biomarker of smoking), zinc (a marker of compliance), and cadmium (the dependent variable) at 3 pre-supplementation visits and at 6 supplementation visits.
  • Determine whether serum cadmium levels (adjusted for serum levels of cotinine) decrease during supplementation with VisiVite Smoker's Formula.
  • Determine if increased cadmium levels in the blood of cigarette smokers can be correlated with decreased mismatch repair.
  • Determine if administration of zinc-containing supplements reverses cadmium-induced inhibition of mismatch repair.

OUTLINE: This is an open-label, nonrandomized study.

Patients receive oral zinc supplements once daily for 12 weeks in the absence of unacceptable toxicity.

Blood, serum, and urine are collected once weekly for 3 weeks before beginning treatment and in weeks 5, 6, 9, 12, 15, and 17 for biomarker/laboratory analysis. Samples are examined for cadmium, zinc, and cotinine levels by atomic absorption spectrophotometry, expression of mismatch repair proteins (MSH2, MSH6, MSH3, MLH1, and PMS2), levels of messenger RNA by reverse transcriptase-polymerase chain reaction, and microsatellite instability by gel electrophoresis.

After completion of study therapy, patients are followed for 5 weeks.

Interventional
Phase 2
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Prevention
  • Bladder Cancer
  • Cervical Cancer
  • Esophageal Cancer
  • Gastric Cancer
  • Head and Neck Cancer
  • Kidney Cancer
  • Leukemia
  • Liver Cancer
  • Lung Cancer
  • Pancreatic Cancer
  • Tobacco Use Disorder
Dietary Supplement: zinc oxide
Oral daily dietary supplement containing 80 mg Zinc oxide
Not Provided
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Active, not recruiting
61
December 2015
October 2006   (final data collection date for primary outcome measure)

DISEASE CHARACTERISTICS:

  • Currently smoking ≥ 1 pack (20 cigarettes) per day
  • Baseline cadmium level ≥ 0.5 μg/L

PATIENT CHARACTERISTICS:

  • Negative pregnancy test
  • Fertile patients must use effective contraception
  • No known gastrointestinal upset due to zinc vitamins or lozenges

PRIOR CONCURRENT THERAPY:

  • At least 2 weeks since prior and no other concurrent vitamins and zinc supplements
Both
21 Years and older
No
Contact information is only displayed when the study is recruiting subjects
United States
 
NCT00376987
CDR0000495325, CCCWFU-98903, CCCWFU-BG03-538
No
Comprehensive Cancer Center of Wake Forest University
Comprehensive Cancer Center of Wake Forest University
National Cancer Institute (NCI)
Principal Investigator: Gary G. Schwartz, MD, PhD, MPH Comprehensive Cancer Center of Wake Forest University
Comprehensive Cancer Center of Wake Forest University
July 2013

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP