Effect of Exenatide, Sitagliptin or Glimepiride on Functional ß -Cell Mass

Condition(s) targeted: Pre-diabetes; Type 2 Diabetes

Intervention: Exenatide (Drug); Sitagliptin (Drug); Glimepiride (Drug)

Phase: N/A

Status: Recruiting

Sponsored by: University of Pennsylvania

Official(s) and/or principal investigator(s):
Michael Rickels, M.D., M.S., Principal Investigator, Affiliation: University of Pennsylvania, Division of Endocrinology, Diabetes & Metabolism

Overall contact:
Armando Leon, Phone: 215-746-2081, Email: armando.leon@uphs.upenn.edu

This study evaluates exenatide, sitagliptin, and glimepiride for the treatment of high blood sugar in patients with impaired fasting glucose or early type 2 diabetes. The purpose of this study is to determine if exenatide and sitagliptin increase the amount of insulin made by the pancreas compared to glimepiride. It is hypothesized that exenatide or sitagliptin will sustain or increase the amount of insulin made by the pancreas in comparison to glimepiride.

Official title: A Randomized, Controlled Trial Comparing the Effect of Exenatide, Sitagliptin or Glimepiride on Functional ß -Cell Mass in Patients With Impaired Fasting Glucose or Early Type 2 Diabetes

Study design: Treatment, Randomized, Open Label, Parallel Assignment, Pharmacodynamics Study

Primary outcome: Effect on functional beta-cell mass as determined by change in ß-cell secretory capacity

Secondary outcome:

Change in acute insulin response to arginine

Change in glucose-potentiation slope

Change in insulin sensitivity

Change in disposition index

Change in PG 50 (the plasma glucose level at which half-maximal insulin secretion is achieved during the glucose-potentiated arginine test)

Detailed description: The incidence of type 2 diabetes (T2D) has reached epidemic proportions throughout the world. In the United States more than 1. 5 million new cases of diabetes were diagnosed in 2005, and the estimated prevalence of the disease was over 20 million. Another 54 million Americans are believed to have impaired fasting glucose, which represents a "pre-diabetic" state at increased risk for progression to overt diabetes. T2D ultimately results from an inadequate mass of functional beta-cells, where insufficient beta-cell compensation for insulin resistance leads to the development of impaired glucose tolerance and eventually diabetes. Autopsy studies have demonstrated a decreased beta-cell mass occurring with fasting glucose > 110 mg/dl, consistent with functional studies that demonstrate decreased beta-cell (insulin) secretory capacity beginning in the range of impaired fasting glucose. Strategies that might preserve or expand functional beta-cell mass in vivo would be expected to reverse the progressive deterioration in blood glucose control seen with diabetes. One such strategy involves the incretin hormone glucagon-like peptide-1 (GLP-1), which is trophic for islet beta-cells, having both pro-proliferative and anti-apoptotic effects. However, it is not known whether increasing GLP-1 effects can preserve or enhance functional beta-cell mass in humans. This proposal will determine the effect of increasing GLP-1 levels on functional beta-cell mass in human subjects with impaired fasting glucose (fasting

glucose 110 - 126 mg/dl) or early T2D (fasting glucose 127 - 149 mg/dl) where a critical

window exists for reversing further beta-cell deterioration. GLP-1 effects will be promoted by administration of either the GLP-1 analog, exenatide, or by increasing endogenous GLP-1 levels through administration of the oral DPP4 inhibitor sitagliptin for a 6-month period. To control for the effect of exenatide and sitagliptin on normalization of blood glucose, subjects will be randomized to receive exenatide, sitagliptin or the sulfonylurea glimepiride, the latter being a first-line anti-diabetogenic agent that will serve as an active comparator.

Minimum age: 18 Years. Maximum age: 70 Years. Gender(s): Both.

Criteria:

Inclusion Criteria:

1. Male and female patients age 18 to 70 years.

2. Ability to provide written informed consent

3. Mentally stable and able to comply with the procedures of the study protocol

4. Clinical history compatible with impaired fasting glucose or early T2D as defined by a plasma glucose concentration between 110-149 mg/dl following a 12 hour overnight fast performed off any anti-diabetogenic agent for at least 2 weeks (6 weeks for thiazolidinediones)

5. Stable body weight (+ 5%) for at least 2 weeks

6. Female Patients: Agree to use adequate contraception if reproductively capable. Adequate contraception includes either a hormonal or barrier method, or surgical sterilization.

Exclusion Criteria:

1. Diagnosis of type 1 diabetes

2. Receiving insulin, exenatide (Byetta®), or sitagliptin (Januvia®) treatment or taking > 2 oral anti-diabetogenic agents for the treatment of diabetes

3. BMI > 44 kg/m2

4. Allergy to any sulfa-containing compounds

5. Uncontrolled hypertension (SBP >160 or DBP > 100 mmHg)

6. Uncontrolled hyperlipidemia (triglycerides > 500 or LDL > 160 mg/dl)

7. Elevation of liver function tests > 2 times the upper limit of normal

8. Estimated GFR < 55 ml/min/1. 73m2 (46)

9. Hyperkalemia (serum potassium > 5. 5 mmol/L)

10. Moderate anemia (hemoglobin concentration < 12 g/dl in men and < 11 g/dl in women)

11. Female patients: pregnant or lactating

12. Hepatic cirrhosis

13. Known active alcohol or substance abuse

14. Active cardiovascular disease

15. Use of any investigational agent within 6 weeks of the baseline visit

16. Any medical condition that, in the opinion of the investigator, will interfere with the safe completion of the trial

Armando Leon, Phone: 215-746-2081, Email: armando.leon@uphs.upenn.edu

Rodebaugh Diabetes Center, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States; Recruiting
Armando Leon, Phone: 215-746-2081, Email: armando.leon@uphs.upenn.edu
Cornelia Bakes, Phone: 215-746-2085, Email: cornelia.dalton-bakes@uphs.upenn.edu
Michael R. Rickels, M.D., M.S., Principal Investigator
Mark H. Schutta, M.D., Sub-Investigator

Clinical and Translational Research Center, Hospital of University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States; Recruiting
Armando Leon, Phone: 215-746-2081, Email: armando.leon@uphs.upenn.edu
Cornelia Bakes, Phone: 215-746-2085, Email: cornelia.dalton-bakes@uphs.upenn.edu
Michael R Rickels, M.D., M.S., Principal Investigator

Pennsylvania Hospital, Philadelphia, Pennsylvania 19107, United States; Recruiting
Armando Leon, Phone: 215-746-2081, Email: armando.leon@uphs.upenn.edu
Cornelia Bakes, Phone: 215-746-2085, Email: cornelia.dalton-bakes@uphs.upenn.edu
Stephen G. Rosen, M.D., Sub-Investigator

Michael R. Rickels, M.D., M.S. Faculty Bio

Rodebaugh Diabetes Center

Clinical and Translational Research Center, Hospital of the University of Pennsylvania

Related publications:

King H, Aubert RE, Herman WH. Global burden of diabetes, 1995-2025: prevalence, numerical estimates, and projections. Diabetes Care. 1998 Sep;21(9):1414-31.

[No authors listed] U.K. prospective diabetes study 16. Overview of 6 years' therapy of type II diabetes: a progressive disease. U.K. Prospective Diabetes Study Group. Diabetes. 1995 Nov;44(11):1249-58. Erratum in: Diabetes 1996 Nov;45(11):1655.

Butler AE, Janson J, Bonner-Weir S, Ritzel R, Rizza RA, Butler PC. Beta-cell deficit and increased beta-cell apoptosis in humans with type 2 diabetes. Diabetes. 2003 Jan;52(1):102-10.

Ritzel RA, Butler AE, Rizza RA, Veldhuis JD, Butler PC. Relationship between beta-cell mass and fasting blood glucose concentration in humans. Diabetes Care. 2006 Mar;29(3):717-8. No abstract available.

Kahn SE. Clinical review 135: The importance of beta-cell failure in the development and progression of type 2 diabetes. J Clin Endocrinol Metab. 2001 Sep;86(9):4047-58. Review. No abstract available.

Godsland IF, Jeffs JA, Johnston DG. Loss of beta cell function as fasting glucose increases in the non-diabetic range. Diabetologia. 2004 Jul;47(7):1157-66. Epub 2004 Jul 13.

Ward WK, Bolgiano DC, McKnight B, Halter JB, Porte D Jr. Diminished B cell secretory capacity in patients with noninsulin-dependent diabetes mellitus. J Clin Invest. 1984 Oct;74(4):1318-28.

Starting date: October 2008
Ending date: May 2012
Last updated: August 25, 2009