From the Guidelines
Retatrutide is not currently recommended for use in type 1 diabetes as its effects in this population have not been well-established. The most recent and highest quality study on the treatment of type 1 diabetes is from 2022, which discusses various pharmacologic approaches to glycemic treatment, including GLP-1 receptor agonists and SGLT2 inhibitors 1. However, retatrutide, a novel GLP-1/GIP/glucagon triple receptor agonist, is primarily being investigated for obesity and type 2 diabetes. In type 1 diabetes, patients lack insulin production due to autoimmune destruction of pancreatic beta cells, making insulin therapy essential for their treatment. While retatrutide's glucagon receptor activity might theoretically raise blood glucose levels through increased hepatic glucose production, its simultaneous GLP-1 and GIP effects would likely counteract this by enhancing glucose-dependent insulin secretion from any remaining beta cells and slowing gastric emptying. However, since type 1 diabetes patients have minimal to no functioning beta cells, the insulin-stimulating effects would be limited.
Some key points to consider in the management of type 1 diabetes include:
- Insulin remains the cornerstone of type 1 diabetes management, with adjunctive therapies like GLP-1 receptor agonists sometimes used off-label 1.
- GLP-1 receptor agonists, such as liraglutide, have been studied in clinical trials in people with type 1 diabetes, showing modest A1C reductions, decreases in weight, and reductions in insulin doses 1.
- SGLT2 inhibitors have also been studied in clinical trials in people with type 1 diabetes, showing improvements in A1C, reduced body weight, and improved blood pressure, but are associated with an increased rate of diabetic ketoacidosis 1.
- Patients with type 1 diabetes should continue their prescribed insulin regimen and consult their endocrinologist before considering any experimental treatments like retatrutide.
It is essential to prioritize the patient's safety and well-being, and insulin therapy should not be discontinued or altered without consulting a healthcare professional. The potential risks and benefits of adjunctive agents, including retatrutide, should be carefully evaluated, and patients should be closely monitored for any adverse effects.
From the Research
Impact of Retatrutide on Blood Sugar Levels in Type 1 Diabetes
- The provided studies do not directly address the impact of Retatrutide on blood sugar levels in type 1 diabetes, as they primarily focus on its effects in type 2 diabetes and obesity 2, 3, 4, 5, 6.
- However, it is known that Retatrutide is a glucagon receptor agonist, which could potentially affect blood sugar levels by influencing glucagon's role in glucose metabolism.
- In type 2 diabetes, Retatrutide has been shown to improve glycemic control, with significant reductions in HbA1c levels 2.
- The mechanism of action of Retatrutide, involving the agonism of GLP-1, GIP, and glucagon receptors, suggests that it could have a complex effect on glucose metabolism, potentially impacting blood sugar levels in type 1 diabetes as well.
Potential Effects on Glucagon Receptor
- The glucagon receptor plays a crucial role in regulating blood sugar levels, and its agonism by Retatrutide could lead to increased glucagon secretion, potentially raising blood sugar levels 3.
- However, the net effect of Retatrutide on blood sugar levels would depend on the balance between its actions on the glucagon receptor and its effects on the GLP-1 and GIP receptors, which are involved in insulin secretion and glucose metabolism.
Limitations and Future Directions
- The current evidence does not provide a clear understanding of Retatrutide's impact on blood sugar levels in type 1 diabetes, highlighting the need for further research in this area.
- Future studies should investigate the effects of Retatrutide on blood sugar levels and glucose metabolism in type 1 diabetes, taking into account its complex mechanism of action and potential interactions with other glucose-regulating hormones.