Tirzepatide is currently approved for management of type 2 diabetes, improving glucose control, facilitating weight loss, and improving cardiovascular disease outcomes.
Tirzepatide (Zepbound; Lilly) resulted in an average of 18.5% weight loss and improved glucose control in patients with type 1 diabetes (T1D) and overweight or obesity at 1 year, according to results of a study published in Diabetes Technology and Therapeutics. Currently, tirzepatide is approved for managing type 2 diabetes, improving glucose control, facilitating weight loss, and improving cardiovascular disease outcomes, according to a press release.1,2
Investigators from the University of Colorado Denver aimed to compare a group of adults with T1D who were prescribed off-label tirzepatide versus a group of individuals with T1D who were not using any weight loss medication, according to the press release.2
“Most of the patients with diabetes, both type 1 diabetes (T1D) and T2D, are either overweight or obese in the United States and Western Europe,” the authors stated in the press release. “Using [glucagon-like peptide 1 (GLP-1)] analogs in patients with T1D poses many challenges, but with close follow-up both patients and the health care provider may see many benefits such as significant weight loss and reduction of insulin dose, increased time-in-range on continuous glucose monitoring and improve HbA1c levels.”2
According to the study authors, the only treatment options for T1D are insulin or pramlintide, which is rarely used due to gastrointestinal events, risk of severe hypoglycemia, and the need for multiple injections per day. Many individuals with T1D have obesity or overweight and increased insulin resistance, but also have an increased risk of cardiovascular disease and diabetic kidney disease.1
Investigators included 184 patients with T1D and overweight or obesity between June 2022 and November 2023 at the Barbara Davis Center for Diabetes in Denver. Individuals were also prescribed tirzepatide for at least 3 months, according to the study authors. Individuals were aged 18 to 80, had a body mass index (BMI) of 27 kg/m2 or greater, were on intensive insulin treatment with either multiple daily injections, an insulin pump, or a hybrid closed loop system, and were using a continuous glucose monitoring system. Only 62 individuals were included in the data analysis, according to the study authors. There were also 37 individuals who were overweight or obese that were matched as controls.1
The results showed that BMI decreased by 3.4 kg/m2 at 3 months and 4.3 kg/m2 at 12 months in the tirzepatide group with no significant changes in the control group at either time point. Weight decreased by 9.6% and 18.5%, respectively, in the tirzepatide group. Changes in HbA1c decreased by 0.5% at 3 months and 0.67% at 12 months, with the change significantly larger for the tirzepatide group, according to the study authors.1
The investigators also reported the total daily dose, basal, and bolus insulin dosages decreased significantly in the tirzepatide treatment group at all time points as did mean CGM glucose, according to the results of the study. The mean CGM glucose did not decrease at any time point in the control group, the study authors said.1
