We updated the design of this site on December 18, 2017. Learn more.
ClinicalTrials.gov Menu
IMPORTANT: Due to the lapse in government funding, the information on this web site may not be up to date, transactions submitted via the web site may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted. Updates regarding government operating status and resumption of normal operations can be found at opm.gov.

Vitamin D for Established Type 2 Diabetes (DDM2) (DDM2)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT01736865
Recruitment Status : Completed
First Posted : November 29, 2012
Last Update Posted : June 10, 2016
Information provided by (Responsible Party):

Study Description
Brief Summary:
This research study in adults with established type 2 diabetes will test whether daily vitamin D supplementation affects how the body processes glucose (sugar).

Condition or disease Intervention/treatment Phase
Type 2 Diabetes Drug: Cholecalciferol Drug: Placebo Phase 2 Phase 3

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 124 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Vitamin D for Established Type 2 Diabetes (DDM2)
Study Start Date : December 2012
Primary Completion Date : August 2015
Study Completion Date : August 2015

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Vitamin D
U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Placebo Comparator: placebo
One placebo pill daily for 1 year
Drug: Placebo
Active Comparator: cholecalciferol
One cholecalciferol pill daily for 1 year
Drug: Cholecalciferol

Outcome Measures

Primary Outcome Measures :
  1. Disposition index [ Time Frame: 6 months ]
    Disposition index by the insulin secretion sensitivity index-2 (ISSI-2)

Secondary Outcome Measures :
  1. Change in glycemia [ Time Frame: 6 and 12 months ]
    Change in glycemia (categorical variable, composite outcome) defined as [1] a decrease in diabetes medications or [2] a reduction of equal to or more than 0.4 HbA1c units from baseline without increasing medications.

Other Outcome Measures:
  1. Hemoglobin A1c [ Time Frame: 6 and 12 months ]
  2. Change in diabetes medications [ Time Frame: 6 and 12 months ]
  3. Variability of response to vitamin D supplementation in subgroups. [ Time Frame: 6 and 12 months ]
    Variability of response to vitamin D supplementation in subgroups defined by baseline characteristics: (1) race; (3) 25OHD concentration; (3) diabetes treatment.

  4. Effect of vitamin D supplementation on blood 25-hydroxyvitaminD concentration [ Time Frame: 6 and 12 months ]
  5. Cardiovascular risk factors [ Time Frame: 6 and 12 months ]
    Cardiovascular risk factors defined as blood pressure, lipid profile, C-reactive protein and urine albumin excretion

Eligibility Criteria

Information from the National Library of Medicine

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:   25 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Established type 2 diabetes, defined by one of the following two criteria:
  • Age ≥ 25 years and ≤ 75 years
  • BMI: 23 to 40 kg/m2 inclusive
  • Provision of signed and dated written informed consent prior to any study procedures.

Major Exclusion Criteria

  • "Severe" diabetes defined by one of the following criteria:
  • - (a) Symptoms of hyperglycemia;
  • - (b) Screening HbA1c ≥ 7.5 [may indicate potential for rapid progression during the trial necessitating need to amplify diabetes-specific pharmacotherapy]
  • History of nephrolithiasis or hypercalcemia
Contacts and Locations

Information from the National Library of Medicine

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): NCT01736865

United States, Massachusetts
Tufts Medical Center
Boston, Massachusetts, United States, 02111
United States, Ohio
Cincinnati VA Medical Center
Cincinnati, Ohio, United States
Sponsors and Collaborators
Tufts Medical Center
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Tufts Medical Center
ClinicalTrials.gov Identifier: NCT01736865     History of Changes
Other Study ID Numbers: DK76092-06
R01DK076092 ( U.S. NIH Grant/Contract )
First Posted: November 29, 2012    Key Record Dates
Last Update Posted: June 10, 2016
Last Verified: June 2016

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 2
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Vitamin D
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents