Glucagon-like Peptide-1 Receptor Agonists: A Class Update for Treating Type 2 Diabetes

Current management options for treating type 2 diabetes are diverse. Many different classes of antidiabetes therapies are used in clinic, and several new candidates are in late-phase clinical trial. This therapeutic abundance is a windfall for patients because it facilitates individualized patient care. Evidence-based positioning of these agents is challenging, however, requiring comprehensive and balanced familiarity with each drug class. In this review, I provide a clinical update of glucagon-like peptide-1 receptor agonists (GLP-1RAs), a class of incretin-based, injectable antidiabetes therapies which improve fasting and postprandial blood glucose control through glucose-dependent pancreatic islet cell hormone secretion without significant risks for hypoglycemia. Chronic use of GLP-1RAs also promotes body weight loss through stimulation of GLP-1 receptors localized in hypothalamic satiety centres that regulate appetite, resulting in reduced caloric intake. Since 2005, when GLP-1RAs first received regulatory approval for type 2 diabetes, this class has expanded to include long-acting, once-weekly GLP-1RAs. Recent cardiovascular outcome trials demonstrate that long-term use of GLP-1RAs (liraglutide and semaglutide) reduce cardiovascular and renal complications of diabetes. Illustrating that GLP-1RAs are favourable in high-risk patients with type 2 diabetes. This review provides a clinical appraisal of the GLP-1RA class, highlighting intraclass similarities and differences, summarizing the clinical development of incretin-based diabetes therapies and focusing on currently approved GLP-1RAs. The review also discusses the implications of structural differences between GLP-1RA molecules and comments on the risks and benefits associated with GLP-1RAs and their positioning in treating type 2 diabetes.