Glucagon-like peptide 1 receptor agonists in type 1 diabetes mellitus

The role of glucagon-like peptide 1 receptor agonists (GLP-1 RAs) in the treatment of type 1 diabetes mellitus (T1DM), including efficacy and safety evidence, is reviewed.

Currently approved treatment options for glycemic control in T1DM include insulin, which combats insulin deficiency but does not effectively target disease progression or alpha cell dysfunction; and pramlintide, whose use requires multiple daily doses and involves a high likelihood of gastrointestinal side effects. GLP-1 RAs have a unique mechanism of action in T1DM, addressing alpha cell dysfunction and thereby suppressing inappropriate glucagon secretion. GLP-1 RA dosing varies from once weekly to twice daily, and the class is well tolerated in patients with type 2 diabetes. Among the GLP-1 RAs, exenatide and liraglutide have been studied in patients with T1DM, with published evidence consistently demonstrating weight loss, decreases in total daily insulin requirements, and modest improvements in glycemic control. GLP-1 RA therapy appears to be well tolerated in patients with T1DM and is associated with nonsignificant increases in hypoglycemia risk.

GLP-1 RA therapy represents an important add-on therapy option for achieving decreased insulin doses, weight loss, and modest improvements in HbA1c levels without significantly increasing hypoglycemia risk in patients with T1DM. Patients who have detectable C-peptide and/or are overweight or cannot achieve glycemic goals without hypoglycemia have been found to benefit the most from GLP-1 RA therapy. Further studies are warranted to evaluate these agents' potential impact on clinical outcomes such as microvascular and macrovascular complications.