Efficacy and Safety of Alogliptin Combined With Pioglitazone in Treating Subjects With Type 2 Diabetes Mellitus.

Over the past 30 years, the prevalence of diabetes has increased dramatically throughout the world due to population growth, aging, urbanization, increasing obesity, and physical inactivity. The total number of people with type 2 diabetes mellitus is projected to rise from 171 million in 2000 to 366 million in 2030. The incidence of type 2 diabetes mellitus in the United States alone is expected to increase from approximately 17 to 30.3 million by the year 2030. Type 2 diabetes mellitus is associated with a number of long-term microvascular and macrovascular complications associated with a reduced quality of life and increased morbidity and mortality. It is anticipated that the increasing incidence of type 2 diabetes mellitus will place an ever-increasing burden on families, increase national expenditures for health care services, and decrease worker productivity. 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 achieving 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 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. Given the complementary mechanisms of action of alogliptin (stimulation of insulin secretion) and pioglitazone (enhancement of insulin sensitivity), the goal of this study is to evaluate the efficacy of the combination of alogliptin with pioglitazone in patients who are inadequately controlled on metformin. Study participation is anticipated to be approximately 7 months.