Madrid – Treatment with semaglutide and tirzepatide leads to significant weight loss and improves blood sugar control in people with type 1 diabetes (T1D) who are overweight or obese, according to new research published Dr. Janet Snell-Bergeon from the Barbara Davis Center for Diabetes at the University of Colorado in Aurora, USA, at the annual meeting of the European Association for the Study of Diabetes (EASD) in Madrid [1,2].
Patients with type 1 diabetes who used semaglutide lost an average of 9% of their body weight, while patients who used tirzepatide lost more than 20% of their body weight. In the tirzepatide group, the amount of insulin could be reduced.
The two relatively new drugs are approved for the treatment of type 2 diabetes and for weight loss. In type 2 diabetes, they help the body produce more insulin when needed, reduce the amount of glucose produced by the liver and slow down the digestion of food. All of this helps to lower blood sugar levels.
And although they are not approved to treat type 1 diabetes, they are increasingly being prescribed off-label to overweight or obese patients with T1D.
USA: Majority of patients with type 1 diabetes are overweight or obese
“Some of the mechanisms by which semaglutide and tirzepatide lower blood sugar in type 2 diabetes may also be important in type 1 diabetes,” said study leader Snell-Bergeon at the congress press conference.
Some of the mechanisms by which semaglutide and tirzepatide lower blood sugar in type 2 diabetes may also be important in type 1 diabetes. Dr. Janet Snell-Bergeon
The expert pointed out that in the USA, two thirds of patients with type 1 diabetes are overweight or obese. The fact that more and more people with type 1 diabetes are becoming overweight is partly due to the intensive insulin therapy that is necessary to control blood sugar, explained Snell-Bergeon.
“Semaglutide and tirzepatide can lead to significant weight loss and improve blood sugar levels, especially in these patients. This could reduce their risk of complications of obesity and diabetes, such as heart disease, eye, nerve and kidney problems.” However, there had previously been no data on how effective the drugs were in patients with type 1 diabetes.
Retrospective study over 1 year
To fill this gap, Snell-Bergeon and colleagues investigated the effectiveness of the two drugs in T1D patients at the Barbara Davis Center for Diabetes in a retrospective study.
The study reviewed the medical records of 100 adults with T1D, 50 of whom were prescribed semaglutide and 50 of whom were prescribed tirzepatide. The majority – 84% of patients on semaglutide and 100% of patients on tirzepatide – were overweight or obese.
Participants were matched for age, gender, diabetes duration, BMI and HbA1c with 50 control subjects (T1D patients without semaglutide and tirzepatide) and weight loss was compared.
Mean age (40 vs. 41 years), gender (71 vs. 72% female), duration of diabetes (26 vs. 27 years), BMI (34 vs. 34 kg/m2), and HbA1c (7.3% vs. 7.3%) did not differ between those who received the medication and the control subjects.
Data were collected at the beginning of the study (before starting medication-assisted weight loss) and then for up to one year for each participant.
Weight loss twice as high with tirzepatide as with semaglutide
All participants took insulin for their diabetes. Insulin pumps were used by 75% of those receiving medication and by 80% of the control subjects. The other patients injected insulin several times a day.
The results show that participants in the semaglutide and tirzepatide groups lost significantly more weight than the control group. Almost all drug-treated patients lost at least 5% of their body weight (77% of semaglutide users, 93% of tirzepatide users), compared with 14% of the control group. And 47% of semaglutide users and 87% of tirzepatide users lost at least 10% of their body weight. No participant in the control group lost more than 10%.
Patients taking tirzepatide lost more than twice as much weight as those taking semaglutide. Semaglutide users lost an average of 9.1% of their body weight, or 19.2 lb (8.7 kg), over 12 months. Their BMI decreased an average of 3 kg/m2 over 12 months. Tirzepatide users lost an average of 21.4% of their body weight, or 49.4 lb (22.4 kg), after 12 months. Their BMI decreased an average of 7.5 kg/m2 after 12 months.
“Weight loss of this magnitude has been observed in other studies of these drugs and likely reduces the risk of a number of obesity-related consequences, including heart disease and insulin resistance,” Snell-Bergeon said.
Insulin consumption was reduced by 18% in the tirzepatide group
In contrast, control subjects had gained some weight on average (0.4%) after 12 months. Blood sugar levels, or glycemic control, improved to a similar extent in participants taking the medication. There was no difference in weight loss between patients using an insulin pump and those taking insulin injections.
However, patients in the tirzepatide group were able to reduce the amount of insulin they needed. Taking into account their lower body weight and examining the daily insulin dose per kg of body weight, after 12 months of treatment, insulin dose had fallen by 0.13 units/kg/day – a reduction of 18%.
Snell-Bergeon viewed this as a “significant reduction and an indication that insulin resistance has improved.”
During the study period, no participant was hospitalized due to severe hypoglycemia or ketosis.
“We think that treatment with semaglutide and tirzepatide will lead to significant weight loss and improved blood sugar control in adults with type 1 diabetes,” said Snell-Bergeon. The study authors classify the drugs as a valuable addition to insulin in the treatment of type 1 diabetes.
However, randomized control studies are necessary to ensure effectiveness and safety, explained Snell-Bergeon. The data from the retrospective study should be supplemented in the foreseeable future. As the expert reported, a randomized controlled study on semaglutide and tirzepatide is currently underway at the Barbara Davis Center for Diabetes. She expects the first data to be available at the end of the year.
