Study to Assess Safety & Efficacy of Sitagliptin as Initial Oral Therapy for Treatment of Type 2 Diabetes Mellitus in Pediatric Participants. (MK-0431-083)

Inclusion Criteria

• Type 2 Diabetes Mellitus (T2DM)
• Has not received treatment with an antihyperglycemic agent (AHA) for ≥12 weeks prior to the Screening Visit/Visit 1, or is on a stable dose of insulin (without any other AHA) for at least 12 weeks prior to the Screening Visit/Visit 1. At screening, participants on insulin doses that are not stable can have their insulin doses adjusted and be eligible to participate after their dose remains stable for ≥12 weeks, if they meet all other eligibility criteria. In India, only participants on stable doses of insulin will be eligible.
• An A1C of ≥6.5% and ≤10.0% (For participants on insulin: an A1C ≥7.0% and ≤10.0%).

Exclusion Criteria

• History of type 1 diabetes mellitus, autoimmune diabetes mellitus or has a positive antibody screen for anti-GAD (Glutamic Acid Decarboxylase) or (Islet cell autoantigen) ICA-512.
• Known monogenic diabetes, secondary diabetes, or a genetic syndrome or disorder known to affect glucose tolerance other than diabetes.
• Symptomatic hyperglycemia and/or moderate to large ketonuria and/or positive test for ketonemia requiring immediate initiation of antihyperglycemic therapy.
• Previously taken a DPP-4 (Dipeptidyl peptidase-4) inhibitor (such as sitagliptin, vildagliptin, alogliptin, or saxagliptin) or GLP-1 (Glucagon-like peptide-1) receptor agonist (such as exenatide or liraglutide).
• Hypersensitivity or contraindication (according to the product circular in the country of the investigational site) to metformin.
• Chronic treatment with a medication known to cause weight gain within 30 days of study start or weight loss or increased blood glucose within 8 weeks of study start or treated with an anti-psychotic within the past 12 weeks.
• On a weight loss program and not in the maintenance phase or have undergone bariatric surgery within 12 months prior to study start.
• On or likely to require treatment with ≥14 consecutive days or repeated courses of pharmacologic doses of corticosteroids.
• Undergone a surgical procedure within the prior 4 weeks or has major surgery planned during the study.
• History of congenital heart disease or cardiovascular disease other than hypertension.
• Medical history of active liver disease (other than non-alcoholic hepatic steatosis), including chronic active hepatitis B or C, primary biliary cirrhosis, or symptomatic gallbladder disease.
• Active nephropathy (i.e., nephrotic syndrome or glomerulonephritis).
• Chronic myopathy, mitochondrial disorder, or a progressive neurological or neuromuscular disorder (e.g., polymyositis, or multiple sclerosis).
• Human immunodeficiency virus (HIV) as assessed by medical history.
• Clinically significant hematological disorder (such as aplastic anemia, thrombocytopenia, myeloproliferative or myelodysplastic syndrome).
• Under treatment for hyperthyroidism.
• Exhibits abnormal growth patterns or is being treated with growth hormone.
• History of malignancy or clinically important hematologic disorder.
• History of idiopathic acute pancreatitis or chronic pancreatitis.
• Known history of recreational or illicit drug use, or of alcohol abuse or dependence (within the past year).
• Donated blood products or has had phlebotomy of >10% of estimated total blood volume within 8 weeks of signing informed consent, or intends to donate blood products or receive blood products within the projected duration of the study.
• Pregnant, has a positive urine pregnancy test at Screening Visit/Visit 1, is expecting to conceive within the projected duration of the study, or is breast-feeding.
• Exclusionary laboratory values.