From the Guidelines
Yes, patients with type 1 diabetes mellitus (T1DM) can take Glucagon-like peptide-1 (GLP-1) receptor agonists as an adjunct therapy to insulin. The most recent and highest quality study, published in 2024 1, shows that GLP-1 receptor agonists, such as liraglutide, can modestly reduce A1C levels (0.4%), decrease weight (5 kg), and reduce insulin doses in patients with T1DM.
Key Points to Consider
- GLP-1 medications can help reduce post-meal blood glucose spikes, decrease insulin requirements, promote weight loss, and potentially reduce glycemic variability in T1DM patients.
- Insulin therapy remains essential and cannot be replaced by GLP-1 medications since people with T1DM cannot produce insulin.
- When adding a GLP-1 medication, insulin doses typically need to be reduced by approximately 10-20% initially to prevent hypoglycemia, with further adjustments based on blood glucose monitoring.
- The main side effects include nausea, vomiting, and delayed gastric emptying, as well as a small increased risk of diabetic ketoacidosis that requires monitoring.
- These medications should be initiated under close medical supervision with frequent blood glucose monitoring and insulin dose adjustments, as suggested by the 2023 standards of care in diabetes 1.
Important Considerations
- The use of GLP-1 receptor agonists in T1DM is not FDA-approved, but they can be used off-label as an adjunct therapy to insulin.
- The risks and benefits of adjunctive agents continue to be evaluated, with consensus statements providing guidance on patient selection and precautions, as noted in the 2024 standards of care in diabetes 1.
- Other studies, such as the 2017 American Diabetes Association standards of medical care in diabetes 1, also support the use of GLP-1 receptor agonists in T1DM, but the 2024 study provides the most recent and highest quality evidence.
From the FDA Drug Label
Limitations of Use: • Not indicated for use in type 1 diabetes mellitus or treatment of diabetic ketoacidosis (1).
Limitations of Use: • Not indicated for use in type 1 diabetes mellitus or treatment of diabetic ketoacidosis (1).
A patient with type 1 diabetes mellitus (T1DM) should not take GLP-1 receptor agonists, such as semaglutide, as it is not indicated for use in this patient population 2, 2.
From the Research
GLP-1 Receptor Agonists in Type 1 Diabetes Mellitus (T1DM)
- GLP-1 receptor agonists have been studied as a potential adjunctive therapy to insulin in T1DM patients 3, 4, 5, 6, 7
- These studies have shown that GLP-1 receptor agonists can reduce average blood glucose, blood glucose variability, and daily insulin requirement in T1DM patients 3, 6, 7
- The use of GLP-1 receptor agonists in T1DM has also been associated with weight loss and improved glycemic control without an increase in hypoglycemia 4, 6, 7
Efficacy and Safety of GLP-1 Receptor Agonists in T1DM
- The efficacy and safety of GLP-1 receptor agonists in T1DM have been evaluated in several studies, with most studies showing significant reductions in hemoglobin A1C, plasma glucose concentration, body weight, and insulin doses 3, 4, 6, 7
- Adverse effects of GLP-1 receptor agonists in T1DM have been mostly gastrointestinal in nature, but have been mild and transient 4, 6, 7
- However, some studies have noted that the effect of GLP-1 receptor agonists on HbA1c in T1DM patients is inconsistent, with some studies showing no clinically relevant effect on HbA1c 4
Potential Benefits of GLP-1 Receptor Agonists in T1DM
- GLP-1 receptor agonists may be beneficial in T1DM patients who are experiencing adverse effects from insulin, those who are not at their A1C goal but hypoglycemia prevents insulin titration, and those who may benefit from weight loss 6
- The use of GLP-1 receptor agonists in T1DM may also help to reduce insulin requirements or delay the absolute dependence on insulin administration in new-onset T1DM patients 5