Diabetes
Conditions
Brief summary
This is a research study to find out how different people respond to a medication called sitagliptin. Sitagliptin is an FDA approved medication that is used to treat diabetes. We are asking for healthy, non-diabetic volunteers to participate in this 7-week study. If you agree to participate, you will take part in 2 clinic visits that are 4-6 weeks apart. At the clinic visits you will have an oral glucose tolerance test (OGTT) and other blood tests to see how your body processes glucose (sugar). An OGTT is a test in which your drink glucose and then blood samples are taken afterward at specific time points to measure glucose and insulin in your blood. Each clinic visit will last about 5 hours.
Interventions
PROCEDUREOral Glucose Tolerance Test
Three hour glucose tolerance test
Sponsors
University of Maryland, Baltimore
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* • Age: \>18 years old * Members of Old Order Amish community in Lancaster, PA
Exclusion criteria
* • Pregnancy (reproductive age women will undergo pregnancy tests immediately before receiving the drug) * Diabetes: HbA1c \> 6.5% or fasting plasma glucose \>126 mg/dL * Estimated glomerular filtration rates (eGFR) \<60 mL/min/1.73 m2 * Anemia: hematocrit \< 35% * Thyroid status: TSH\<0.4 or TSH\>5.5 * ALT or AST in excess of 2X upper limit of normal * Drugs that in the physician's judgment would alter response to sitagliptin * Significant health issues that in the physician's judgment could increase the risk for participants.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Sitagliptin-induced enhancement of early insulin secretion | 6 weeks | This represents the incretinomimetic effect of sitagliptin, which contributes importantly to the mechanism whereby DPP4is decrease HbA1c in T2D patients. Because histograms for sitagliptin-induced increase in our index of early insulin secretion (T30:T60) demonstrated a skewed distribution, we will apply a logarithmic transformation of data which yields a normal distribution. Thus, the drug effect is defined as: log(T30:T60 ins)sita - log(T30:T60 ins)control. |
| Sitagliptin-induced change in glucose tolerance | 6 weeks | Sitagliptin-induced change in glucose tolerance. This is a consequence of enhanced insulin secretion, which reflects most closely the desired effect of the drug to decrease plasma glucose and decrease HbA1c. Because histograms for sitagliptin-induced increase in our index of glucose tolerance (T30:T60) demonstrated a skewed distribution, we will apply a logarithmic transformation of data which yields a normal distribution. Thus, the drug effect is defined as: log(T30:T60 gluc)sita - log(T30:T60 gluc)control. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Area under the curve for insulin concentration | 6 weeks | Area under the curve of insulin concentration measured from oral glucose tolerance test using trapezoidal rule |
| Area under the curve for glucose concentration | 6 weeks | Area under the curve for glucose concentration measured from the oral glucose tolerance test using the trapezoidal rule |
| Area under the curve for intact GIP | 6 weeks | Area under the curve for levels of intact GIP during the first hour of the OGTT as calculated by the trapezoidal rule |
| Area under the curve for intact GLP1 | 6 weeks | Area under the curve for levels of intact GLP1 during the first hour of the OGTT as calculated by the trapezoidal rule |
| Area under the curve for C-peptide levels | 6 weeks | Area under the curve for C-peptide levels as a direct index of insulin secretion |
Countries
United States
Contacts
CONTACTAmber L Beitelshees
CONTACTKamah Woelfel
PRINCIPAL_INVESTIGATORAmber L Beitelshees, PharmD, MPH
University of Maryland, Baltimore
PRINCIPAL_INVESTIGATORSimeon I Taylor, MD, PhD
University of Maryland, Baltimore
Outcome results
None listed