CompletedNot Applicable

Improving Metabolic Assessments in Type 1 Diabetes Mellitus Clinical Trials

United States120 participantsStarted 2004-11

Plain-language summary

OBJECTIVE: This study is being conducted by the Type 1 Diabetes TrialNet Study Group, funded by the National Institutes of Health, in collaboration with the European C-Peptide Group. The goal is to evaluate comparability and reproducibility of measures of beta cell function in type 1 diabetes comparing the mixed meal tolerance tests (MMTT) and glucagon stimulation test (GST). These two tests will be compared to assess the relationship between the MMTT and IV (intravenous) Glucagon stimulated C-peptide responses as measured by time to peak C-peptide and AUC (area under the curve) values. Based on the understanding that type 1 diabetes results from an immune mediated loss of pancreatic beta cells, therapeutic trials and newer measures of beta cell function can be evaluated as endpoints for clinical trials. Direct assessment of residual beta cell function is an appropriate endpoint, as retention of beta cell function in patients with T1D is known to result in improved glycemic control and reduced hypoglycemia, retinopathy and nephropathy. Endogenous beta cell function or insulin secretion is best measured by determination of C-peptide (which is co-secreted with insulin in a 1:1 molar ratio). Intervention studies over the past few decades have usually used measurement of C-peptide. However, the relationship between these or other measures of beta cell function has not been well studied. The relative advantages of one measure over another in terms of variability, sensitivity and burden to the subject is unknown. In addition, the optimal conditions for the conduct of the test need to be determined. An important goal is to develop an international consensus about the conduct of metabolic tests in the context of large, multicenter trials involving type 1 diabetes (T1D) by balancing the scientific data with the burden on the subject.

Who can participate

Age range8 Years – 35 Years

SexALL

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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

* Informed consent obtained from participants (over 12 years of age) and parents (for participants below 18 years of age). Assent is obtained from younger children. * Age 8 - 35 years at the time of inclusion * Body weight \> 30 kg * Type 1 diabetes defined by: ADA (American Diabetes Association) criteria or judgment of physician * Duration of diabetes: 1 month to 3\* years (\*The TrialNet Coordinating Center will monitor fasting C-peptide levels as they are reported to ensure that a wide range of values is included. This review may result in widening the duration of diabetes window to allow for subjects with low C-peptide). * Must maintain good glycemic control * Be willing to travel to a TrialNet Clinical Center for a minimum of four separate visits that are spaced 3-10 days apart, and be willing to complete the study within a six week period. Exclusion Criteria: * Actual treatment with drugs influencing beta cell function (e.g. oral hypoglycaemic agents, beta-2-receptor agonists) * Actual treatment with drugs influencing insulin sensitivity (e.g. steroids) * Significant concomitant disease likely to interfere with glucose metabolism (e.g. febrile illness within the prior 3 days) * Expected poor compliance * If a female of child-bearing age, currently pregnant or not using a form of birth control * Any other condition that by the judgement of the investigator may be potentially harmful to the patients

What they're measuring

Stimulated C-peptide response derived from the 2-hour MMTT and the glucagon stimulation test (GST)

Time to peak C-peptide on MMTT, and the peak and AUC values from each test

Co-efficient of reproducibility of the MMTT, and the GST, provided from the duplicate tests within the same individuals

Trial details

NCT IDNCT00105352

SponsorNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Sponsor typeNIH

Study typeINTERVENTIONAL