• Change from Baseline in Glycosylated Hemoglobin [ Time Frame: Weeks 4, 8, 12, 16, and 20 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Fasting Plasma Glucose [ Time Frame: Weeks 1, 2, 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of Marked Hyperglycemia (fasting plasma glucose greater than or equal to 200 mg/dL). [ Time Frame: Weeks 1, 2, 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of Rescue. [ Time Frame: Weeks 1, 2, 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Fasting Proinsulin [ Time Frame: Weeks 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Insulin. [ Time Frame: Weeks 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Proinsulin/Insulin ratio [ Time Frame: Weeks 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in C-peptide. [ Time Frame: Weeks 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of Glycosylated Hemoglobin less than or equal to 6.5%. [ Time Frame: Week 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of Glycosylated Hemoglobin less than or equal to 7.0%. [ Time Frame: Week 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of Glycosylated Hemoglobin less than or equal to 7.5%. [ Time Frame: Week 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of glycosylated hemoglobin decrease from Baseline greater than or equal to 0.5%. [ Time Frame: Week 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of Glycosylated Hemoglobin decrease from Baseline greater than or equal to 1.0%. [ Time Frame: Week 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of Glycosylated Hemoglobin decrease from Baseline greater than or equal to 1.5%. [ Time Frame: Week 26 or Final Visit. ] [ Designated as safety issue: No ]
• Incidence of Glycosylated Hemoglobin decrease from Baseline greater than or equal to 2.0%. [ Time Frame: Week 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Total Cholesterol. [ Time Frame: Weeks 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Low-Density Lipoprotein. [ Time Frame: Weeks 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in High-Density Lipoprotein. [ Time Frame: Weeks 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Triglycerides. [ Time Frame: Weeks 4, 8, 12, 16, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Nuclear Magnetic Resonance Lipid Fractionation [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Free Fatty Acids [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Plasminogen Activator Inhibitor-1. [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in high-sensitivity C-Reactive Protein. [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Adiponectin. [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Body Weight. [ Time Frame: Weeks 8, 12, 20, and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Calculated Homeostatic Model Assessment Insulin Resistance [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Homeostatic Model Assessment Beta Cell Function. [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Apolipoprotein A1. [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Apolipoprotein A2. [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Apolipoprotein B. [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]
• Change from Baseline in Apolipoprotein C-III. [ Time Frame: Weeks 12 and 26 or Final Visit. ] [ Designated as safety issue: No ]

The purpose of this study is to evaluate the combination of SYR-322 and pioglitazone in subjects with type 2 diabetes mellitus who are inadequately controlled with diet and exercise alone.

There are approximately 19 million people in the United States who have been diagnosed with diabetes mellitus, of which 90% to 95% is type 2. The prevalence of type 2 diabetes varies among racial and ethnic populations and has been shown to correlate with age, obesity, family history, history of gestational diabetes, and physical inactivity. Over the next decade, a marked increase in the number of adults with diabetes mellitus is expected, placing an ever-increasing burden on families and the health care system.

Current pharmacologic interventions for type 2 diabetes mellitus include a diverse range of antidiabetic medications with different mechanisms of action including insulin and insulin analogues, sulfonylureas, metformin, meglitinides, thiazolidinediones, inhibitors of alpha- glucosidase, analogs of glucagon-like peptide-1, and synthetic analogues of human amylin. Despite the variety of medications, many have clinically important or potentially life-threatening side effects, restricted use in many subpopulations, concerns with long-term tolerability, and challenges related to compliance due to side effects and route of administration. All of these reasons contribute to the difficulties patients have reaching the target glycosylated hemoglobin level less than 7%.

SYR-322 (alogliptin) is a selective, orally available inhibitor of the dipeptidyl peptidase-4 enzyme. Dipeptidyl peptidase-4 enzyme is thought to be primarily responsible for the in vivo degradation of 2 peptide hormones released in response to nutrient ingestion, namely glucagon-like peptide-1 and glucose-dependent insulinotropic peptide. Both peptides exert important effects on islet beta cells to stimulate glucose-dependent insulin secretion as well as regulating beta cell proliferation and cytoprotection. Glucagon-like peptide-1, but not glucose-dependent insulinotropic peptide, inhibits gastric emptying, glucagon secretion, and food intake. Glucose-dependent insulinotropic peptide has been shown to enhance insulin secretion by direct interaction with a glucose-dependent insulinotropic peptide -specific receptor on islet beta cells. The glucose-lowering actions of glucagon-like peptide-1, but not glucose-dependent insulinotropic peptide, are preserved in patients with type 2 diabetes mellitus.

Pioglitazone (ACTOS®) is a thiazolidinedione developed by Takeda Chemical Industries, Ltd. (Osaka, Japan) that is approved for the treatment of type 2 diabetes mellitus. Pioglitazone is a potent and highly selective peroxisome proliferator-activated receptor-gamma agonist that decreases insulin resistance in the periphery and liver resulting in increased insulin-dependent glucose disposal and decreased hepatic glucose output.

As the rate of newly diagnosed cases of type 2 diabetes mellitus continues to grow, so does the need for products that will provide better glycemic control and improved safety and tolerability. SYR-322 and pioglitazone have complementary actions. SYR-322 inhibits the degradation of glucagon-like peptide-1 by inhibiting the enzyme dipeptidyl peptidase IV, thus augmenting glucose-dependent insulin secretion while pioglitazone is a peripheral and hepatic insulin sensitizer. Given the complementary mechanisms of action of SYR-322 (stimulates insulin secretion) and pioglitazone (enhances insulin sensitivity), the addition of combination therapy in treatment naïve type 2 diabetes patients may potentially allow the patients to reach and maintain their glycosylated hemoglobin goal more effectively.

The aim of this study is to evaluate the effectiveness of the combination of SYR-322 with pioglitazone in subjects who are inadequately controlled on diet and exercise alone. Study participation is anticipated to be approximately 8.5 months.

• Drug: SYR-322 and pioglitazone
• Drug: SYR-322
• Drug: Pioglitazone

Inclusion Criteria

• Historical diagnosis of type 2 diabetes.
• Failed treatment with diet and exercise for at least 2 months prior to Screening.
• Is experiencing inadequate glycemic control as defined as glycosylated hemoglobin concentration between 7.5-11%, inclusive.
• Has received any antidiabetic therapy for less than 7 days within 3 months prior to Screening.
• Has a body mass index greater than or equal to 23 kg/m2 and less than or equal to45 kg/m2.
• Fasting C-peptide greater than or equal to 0.8 ng per mL.
• Regular use of other, non-excluded medications is allowed if participant is on a stable dose for at least 4 weeks prior to Screening.
• Females of childbearing potential who are sexually active must agree to use adequate contraception, and can neither be pregnant nor lactating from Screening throughout the duration of the study.
• Must be willing and able to monitor their blood concentrations with a home glucose monitor.

Exclusion Criteria

• Systolic blood pressure greater than or equal to 160 mmHg and diastolic blood pressure greater than or equal to 100 mmHg.
• Hemoglobin less than or equal to 12 g per dL for males and less than or equal to 10 g per dL for females.
• Alanine aminotransferase greater than or equal to 2.5times the upper limit of normal.
• Serum creatinine greater than 2.0 mg per dL.
• Thyroid stimulating hormone level greater than the upper limit of normal range.
• Major illness or debility that in the investigator's opinion prohibits the subject from completing the study.
• Urine albumin to creatinine ratio of greater than 1000 ug per mg at Screening. If elevated, the subject may be rescreened within 1 week.
• History of cancer, other than squamous cell or basal cell carcinoma of the skin, that has not been in full remission for at least 5 years prior to Screening
• History of laser treatment for proliferative diabetic retinopathy within 6 months prior to Screening.
• History of gastroparesis.
• Has New York Heart Association Class I to IV heart failure regardless of therapy.
• History of coronary angioplasty, coronary stent placement, coronary bypass surgery, or myocardial infarction within 6 months prior to Screening.
• History of any hemoglobinopathy that may affect determination of glycosylated hemoglobin.
• History of infection with hepatitis B, hepatitis C, or human immunodeficiency virus.
• History of a psychiatric disorder that will affect participant's ability to participate in the study.
• History of angioedema in association with use of angiotensin-converting enzyme inhibitors or angiotensin-II receptor inhibitors.
• Any alteration in angiotensin-II receptor inhibitors within 2 months prior to Randomization, if applicable.
• History of alcohol (defined as regular or daily consumption of more than 4 alcoholic drinks per day) or substance abuse (defined as illicit drug use) within 2 years prior to Screening.
• Received any investigational drug within 30 days prior to Screening or a history of receipt of an investigational antidiabetic drug within 3 months prior to Screening.
• Previously participated in an investigational study of SYR-322.
• Glycosylated hemoglobin concentration between 7.5-11%, inclusive, and a fasting plasma glucose less than 310 mg per dL.
• At least 75% compliant with the single-blind placebo regimen during the run-in/stabilization period.

• Is required to take or continues taking any disallowed medication, prescription medication, herbal treatment or over-the counter medication that may interfere with evaluation of the study medication, including:

  • antidiabetic agents
  • weight loss drugs
  • investigational antidiabetics
  • oral or systemically injected glucocorticoids