BACKGROUND: Type 2 diabetes (T2D) is an increasingly common endocrine disorder that is characterized by chronic hyperglycemia and tissue compartment abnormalities, including macrovascular and microvascular complications. More than 90% of patients with T2D will be diagnosed and treated in the primary care setting. One of the relatively recent additions to the increasing array of approved antidiabetic medications is the glucagon-like peptide-1 receptor agonist class. Mechanisms of action for glucagon-like peptide-1 receptor agonists include: 1) stimulation of insulin secretion through β-cells, though only when glucose levels are elevated (hence, minimizing risk for hypoglycemia); 2) blunting of glucagon secretion; 3) increased satiety; and 4) decreased rate of release of gastric contents into the small intestine, thereby reducing glycemic load. Recent T2D treatment guidelines encourage individualization of therapy. Many patients still do not achieve optimal glycemic control. Therefore, other treatment options are important.
METHODS: A literature search was performed using PubMed and MEDSCAPE to retrieve abstracts and articles pertinent to topics discussed in this review. Original research articles, reviews, and clinical trial manuscripts were identified based on relevance. Only English language articles were considered. Results In 3 phase 3 registration trials in patients with T2D, once-weekly dulaglutide demonstrated superior efficacy at the primary endpoint to metformin as monotherapy, to sitagliptin as add-on to metformin, and to exenatide twice daily as add-on to metformin and pioglitazone. The safety profile of dulaglutide in these trials is similar to currently available glucagon-like peptide-1 receptor agonists, characterized predominantly by gastrointestinal symptoms (ie, nausea, vomiting, and diarrhea). Based on these results, once-weekly dulaglutide should be a relevant additional treatment option for the management of T2D.
