Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter-2 (SGLT2) inhibitors are widely used off label in patients with type 1 diabetes on automated insulin delivery (AID) systems. The logic is straightforward: Only about half of people using AID manage to achieve A1C levels below 7%, in part because the systems are unable to optimally manage postprandial glucose levels well during the daytime in individuals with type 1 diabetes, and with increasing overweight and obesity, many people require high insulin and need to change their infusion site or patch pump more frequently. 

“People with type 1 diabetes and overweight or obesity may benefit from medications like GLP-1 RAs and SGLT2 inhibitors because with one drug you can kill more than two birds,” said Viral N. Shah, MD, Professor of Endocrinology and Metabolism and Director of Diabetes Clinical Research at Indiana University Center for Diabetes and Metabolic Diseases. “You can reduce weight, which will lower the insulin requirement to optimize the AID and may also reduce cardiovascular risk.”

Dr. Shah will open the Ask the Expert session, Use of GLP-1 RAs and SGLT2i with Automated Insulin Delivery Systems, on Sunday, June 22, from 4:30–6:00 p.m., in Room W185 A–D of the McCormick Place Convention Center. He will share the podium with Anders L. Carlson, MD, Assistant Professor of Medicine, University of Minnesota Medical School, Medical Director of the International Diabetes Center, and Director the HealthPartners Diabetes Program.

Both GLP-1 RAs and SGLT2 inhibitors have been approved by the U.S. Food and Drug Administration (FDA) for use in type 2 diabetes, Dr. Shah noted, and neither has been approved for use in type 1. But recent publications suggest that about 30% of patients with type 1 diabetes are using GLP-1 RAs.

SGLT2 inhibitors have been well studied in type 1 diabetes, Dr. Shah added, and were not approved for use in this population due the increased risk of diabetes-related ketoacidosis (DKA). Risk of DKA is slightly increased in type 2 diabetes, but the FDA judged that the benefits outweigh the risks.

“I don’t think we will get additional SGLT2i trials in type 1 diabetes until we get continuous ketone monitoring to better assess DKA risk,” Dr. Shah said. “These drugs are not as widely used in type 1 as GLP-1 RAs because GLP-1s are not associated with increased risk of DKA.”

At least two clinical trials of GLP-1 RAs in type 1 diabetes are currently under way, he said. Positive results could support FDA approval in type 1 diabetes at some point.

For now, clinicians who use GLP-1 RAs off label should be aware of potential adverse reactions. These drugs can have gastrointestinal side effects, including nausea and vomiting, that can lead to dehydration and may affect kidney function. There are also effects specific to patients using AID.

Expect to adjust insulin and pump settings more frequently, Dr. Shah said. Patients will lose weight and have much improved insulin sensitivity, leading to as much as a 50% reduction in insulin dosing in some individuals.

“We have to watch for that and titrate the insulin dosage,” he cautioned.

Patients with more severe GI side effects should also check their ketones more frequently, Dr. Shah suggested. Severe vomiting, whether due to GLP-1 RAs or some other cause, can contribute to ketosis and potentially DKA.

“There are a lot of real-world studies on the use of GLP-1 RAs and type 1 diabetes,” Dr. Shah said. “These studies can give us some idea on what kinds of things to watch for and what to do even though these medications are being used off-label.”

On-demand access to recorded presentations will be available to registered participants following the conclusion of the 85^th Scientific Sessions, from June 25–August 25.