Tumor Necrosis Factor Decreases Vitamin D Dependant Calcium Absorption

This study has been completed.
Emory University
Information provided by (Responsible Party):
Vin Tangpricha, Atlanta VA Medical Center
ClinicalTrials.gov Identifier:
First received: January 25, 2007
Last updated: January 30, 2013
Last verified: January 2013
This study is a pilot study to determine whether patients with TNFα excess have decreased calcium absorption in response to calcitriol (1,25-dihydroxyvitamin D, the active form of vitamin D) compared to normal controls. This initial pilot study is being done to determine if it is feasible to conduct a study where TNFα could be blocked (e.g., by anti-TNFα therapy such as Enbrel® or Remicade®) to improve vitamin D dependant calcium absorption and thus bone health.

Condition Intervention
Rheumatoid Arthritis
Crohn's Disease
Drug: calcitriol

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Tumor Necrosis Factor-α Induces Vitamin D Resistance in Small Intestinal Calcium Absorption

Resource links provided by NLM:

Further study details as provided by Atlanta VA Medical Center:

Primary Outcome Measures:
  • Intestinal Absorption of Calcium [ Time Frame: 12 Weeks ] [ Designated as safety issue: Yes ]
  • Fractional Absorption of Calcium [ Time Frame: 7 week ] [ Designated as safety issue: No ]
    Fractional absorption of calcium (see citation for complete details)

Enrollment: 9
Study Start Date: January 2007
Study Completion Date: November 2009
Primary Completion Date: August 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Calcitriol
Calcitriol 0.25 mcg orally twice a day for 7 days or calcitriol 0.50 mcg orally twice a day for 7 days.
Drug: calcitriol
0.25 mcg PO BID for 1 week for low dose then 0.25 mcg PO BID for high dose

  Show Detailed Description


Ages Eligible for Study:   18 Years to 50 Years
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Males
  • Age 18 to 50
  • History of Crohn's disease or Rheumatoid Arthritis (cases) or healthy individuals (controls)

Exclusion Criteria:

  • Subjects already taking activated vitamin D medications such as calcitriol, Zemplar®, Hectoral®
  • Vitamin D deficiency defined as 25(OH)D ≤ 20 ng/ml
  • Post-menopausal women (absence of menses for greater than 6 months by history or FSH level >20)
  • History of nephrolithiasis
  • History of hypercalcemia or hypercalciuria
  • Short bowel disease
  • Glucocorticoid use
  • Use of osteoporosis medication (bisphosphonate, calcitonin or teriparatide)
  • Chronic kidney disease (calculated GFR <60 ml/min/1.73 m2)
  • History of hyperparathyroidism (PTH greater than upper limit of normal) or
  • Hypoparathyroidism (PTH below lower limit of normal)
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00427804

United States, Georgia
Atlanta VAMC
Atlanta, Georgia, United States, 30030
Sponsors and Collaborators
Atlanta VA Medical Center
Emory University
Principal Investigator: Vin Tangpricha, M.D. Ph.D. Emory University
  More Information

Responsible Party: Vin Tangpricha, Staff Physician, Atlanta VA Medical Center
ClinicalTrials.gov Identifier: NCT00427804     History of Changes
Other Study ID Numbers: Vitamin D-2007 
Study First Received: January 25, 2007
Results First Received: August 3, 2011
Last Updated: January 30, 2013
Health Authority: United States: Federal Government

Keywords provided by Atlanta VA Medical Center:
Calcium absorption
Vitamin D

Additional relevant MeSH terms:
Arthritis, Rheumatoid
Crohn Disease
Autoimmune Diseases
Connective Tissue Diseases
Digestive System Diseases
Gastrointestinal Diseases
Immune System Diseases
Inflammatory Bowel Diseases
Intestinal Diseases
Joint Diseases
Musculoskeletal Diseases
Rheumatic Diseases
Vitamin D
Bone Density Conservation Agents
Calcium Channel Agonists
Cardiovascular Agents
Growth Substances
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Pharmacologic Actions
Physiological Effects of Drugs
Therapeutic Uses
Vasoconstrictor Agents

ClinicalTrials.gov processed this record on February 10, 2016