Predictive Parameters for Efficacy of Sitagliptin and Metformin Combination

Study Overview
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Brief Summary
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It is well established that inhibition of dipeptidyl peptidase (DPP)-IV reduces glucose levels in both fasting and postprandial states and preserves pancreatic beta cell function in patients with type 2 diabetes. Their mechanism of action is derived from increased incretin (GLP-1) levels, which stimulate insulin secretion as well as insulin biosynthesis and inhibit glucagon secretion from pancreas. Recent studies reported that combination therapy with DPP-IV inhibitors and metformin have additive or synergistic effects in lowering glycose level, preserving beta-cell mass and function as well as enhancing insulin sensitivity. However, there have been few studies about the difference of glucose lowering effect of combination therapy of DPP-IV inhibitors and metformin according to the secretory capacity of pancreas. The researchers hypothesized that combination therapy with DPP-IV inhibitor and metformin may have more favorable glucose lowering effect in type 2 diabetic patients who have preserved pancreatic secretory function. The researchers plan to investigate the difference of glucose lowering effect of 24 weeks treatment with sitagliptin (DPP-IV inhibitor) in combination with metformin according to basal c-peptide and glucagon level in type 2 diabetic patients.

Official Title
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Predictive Parameters for Therapeutic Efficacy of Initial Combination Therapy With Sitagliptin and Metformin in Type 2 Diabetic Patients

Conditions
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Diabetes

Intervention / Treatment
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* Drug: sitagliptin, metformin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Type 2 diabetes HbA1c ≥ 7% Age ≥ 18 Exclusion Criteria: Contraindication to sitagliptin or metformin Pregnant or breast feeding women Reproductive-age women who refuse contraception Type 1 diabetes, gestational diabetes, or diabetes with secondary cause Chronic hepatitis B or C (except healthy carrier of HBV), liver disease (AST/ALT > 3-fold the upper limit of normal) Renal failure (Cr > 2.0) Cancer within 5 years (except squamous cell cancer, cervical cancer, thyroid cancer with appropriate treatment) Not appropriate for oral antidiabetic agent Medication which affect glycemic control Disease which affect efficacy and safety of drugs Other clinical trial within 30 days

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Metformin+Sitagliptin<br>Initial combination of metformin and sitagliptin | Drug: sitagliptin, metformin<br>* sitagliptin 100mg once daily and metformin 500mg twice daily, orally, for 24 weeks.<br>* Other names: Januvia;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The change of HbA1c |  | 52 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fasting Plasma Glucose (FPG) |  | 52 weeks | 
| Postprandial Plasma Glucose (PPG) |  | 52 weeks | 
| C-peptide |  | 52 weeks | 
| Glucagon |  | 52 weeks | 
| Homeostatic model assessment of insulin resistance (HOMA-IR) |  | 52 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Diabetes, Sitagliptin, C-peptide, Glucagon