Metformin to Treat Obesity in Children With Insulin Resistance
Status:
Completed
Trial end date:
2011-05-01
Target enrollment:
Participant gender:
Summary
This study will examine the safety and effectiveness of the medicine metformin to help
overweight children control their food intake, weight, insulin, cholesterol, and triglyceride
(blood fat) levels. Obesity and high insulin levels can lead to high blood pressure,
diabetes, high cholesterol and triglyceride levels and heart disease. Metformin-approved by
the Food and Drug Administration to treat adults with type 2 diabetes mellitus-helps lower
insulin levels and may control weight gain in adults.
Overweight children 6 to 11 years old who are in general good health may be eligible for this
study. Children will be studied at the National Institutes of Health in Bethesda, Maryland.
Candidates will have a medical history and physical examination and fasting blood test, and
will provide a 7-day record of their food intake as part of the screening process. Those
enrolled will be randomly assigned to receive either metformin or placebo (a look-alike
tablet with no active medicine) twice a day for a six month period. After the 6 month study
period, all children will be offered the opportunity to take metformin for another 6 months.
Participants will be hospitalized for 2-3 days for the following procedures: history and
physical examination; fasting blood test; several urine collections; X-ray studies to
determine bone age and amount of body fat and muscle; magnetic resonance imaging (MRI) scan
to measure body fat; "hyperglycemic clamp study" to evaluate insulin resistance; food intake
testing; nutrition consultation; resting metabolic rate; and a "doubly labeled water" test.
For the hyperglycemic clamp study, a catheter (thin flexible tube) is inserted into a vein in
each arm. A sugar solution is given through one tube and blood samples are drawn every 5
minutes through the other to measure insulin. For the food intake testing, the child is asked
about his or her hunger level, then given various foods he or she may choose to eat, then
questioned again at various intervals both during and after finishing eating about his or her
hunger level. The doubly labeled water study involves drinking "heavy water" (water which is
enriched to have special kinds of hydrogen and oxygen). Urine specimens are collected 2, 3
and 4 hours after drinking the water. The child also drinks a special milk shake called a
Scandishake and repeats the calorie intake and hunger study. (Two food intake studies are
done on separate days.) One week after the heavy water test, additional urine samples are
collected one week later.
After completing the tests, the child will begin treatment with metformin or placebo, plus a
daily vitamin tablet. Participants will be followed once a month with a brief history and
physical examination, including a blood test. After 6 months, all of the tests described
above will be repeated. All children who complete the second round of tests-both those who
took metformin and those who took placebo-will be offered metformin for an additional 6
months and will be seen once a month for follow-up evaluations. Parents will not be told
which children received metformin and which received placebo until all children in the study
complete the first 6 months of the trial.
Phase:
Phase 2
Details
Lead Sponsor:
Jack Yanovski, M.D.
Collaborator:
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)