Diabetes
Kevin Willmann
Patients now have the choice of two different automated insulin delivery (AID) systems for the treatment of T2D after the results of a control group study published in NEJM on March 19, 2025, further demonstrated the benefits of AID systems in treating T2D.
The trial, funded by Tandem Diabetes Care, a medical device manufacturer, took place between June 2023 and June 2024 with a total of 319 patients.
The trial was the first randomized evaluation of AID system use for patients with T2D. Tandem, along with members of the research team designed the study, which was conducted at 21 centers in the United States and Canada, including one U.S. Veterans Affairs hospital.
In 13 weeks of the trial, AID system use was associated with a greater reduction in A1C levels for patients with T2D compared with those in the control group who used real-time continuous glucose monitoring (CGM) and continued a pretrial insulin-delivery method. Similarly, AID system use was also reported to benefit patients with T2D in CGM-measured hyperglycemia and related outcomes. Patients had a glucose level of 70 to 180 mg per deciliter with a mean time of 3.4 hours per day longer using AID systems than using CGM alone. The frequency of hypoglycemia was low at baseline and remained low during the trial.
This finding was consistent with other studies involving patients with T2D.
Due to the results of the study, the Tandem Control-IQ AID system received FDA clearance in February 2025 for use in people with T2D and became available to patients in March 2025.
FDA’s approval of Tandem’s AID system followed similar approval in August 2024 of an AID system developed for treatment of T2D by Insulet, a manufacturer of insulin management systems.
AID system use for diabetes
Roy Beck, MD, executive director of the Jaeb Center for Health Research and one of the study authors, said the first AID system—Medtronic 670G—was approved by FDA in 2016 for T1D. This was followed by FDA approval for several other systems, including those from Insulet, Tandem, and BetaBionics—all for treating T1D.
“AID systems were originally developed for type 1 diabetes as all individuals with type 1 diabetes require insulin and many were already using an insulin pump plus CGM,” Beck said. “Tying the pump and CGM together with an algorithm to automate insulin delivery made a lot of sense.”
The study authors noted that the benefits of using AID systems for treating T1D is well-established. Seeing this success, Beck said they wanted to see whether the same systems would work just as well for those with T2D requiring insulin.
Study design
For the study design, 215 patients were randomly assigned to the AID system group and 104 to the control group.
The patient age range was 19 to 87 years.
Patients in the trial had T2D for at least 6 months. All received multiple daily injections of insulin, with at least one containing rapid-acting insulin per day, or were using an insulin pump at least 3 months prior to enrollment in the study. The study design allowed mixed insulin use with a rapid-acting component, as well as concurrent treatment with non-insulin glucose-lowering or weight-reduction medications, if the dose was stable for the prior 3 months.
Patients were randomly assigned in a 2:1 ratio to receive AID system treatment or to continue their pretrial insulin-delivery method (control group). Both groups received CGM. Prior to randomization, baseline CGM data were collected while patients continued to receive their pretrial insulin-delivery regimen.
Benefits of AID system use for T2D
Beck noted one of the important findings from the study was how a benefit was achieved whether or not patients continued use of a drug such as Ozempic or regardless of how individual patients determined the amount of insulin bolus to give with a meal. In either case, they benefited from AID system use.
Although previous studies of AID system use have been conducted involving patients with T2D, participants in past studies were treated without a control group. The NEJM study was the first to include a control group, which was an important element in showing the effectiveness of AID systems in treating T2D.
“The randomized trial with a control group is important to be able to distinguish the effect of CGM alone, plus the effect we usually see of improvement just being in a study [effect] versus the effect of AID,” Beck said. “In our study, about half of the participants were using a GLP-1 or a SGLT-2 drug but still had high glucose levels. We found that adding AID on top of those drugs was beneficial.”
The participants not using these drugs also showed benefit. The worse a participant’s glucose control was before the study, as measured by A1C, the greater the improvement they had on average, said Beck. ■