Use of an automated insulin delivery system improved glucose control among people with type 2 diabetes, a study conducted by Mount Sinai endocrinologist Carol J. Levy, MD, CDCES, has shown.

The system tested, from Tandem Diabetes Care, comprises a t:slim X2 insulin pump and a continuous glucose monitor (CGM), both worn on the body. Incorporated within the insulin pump is software called “Control-IQ” that uses the glucose numbers and trends from the CGM to direct semi-automated insulin delivery. This system was approved in early 2020 based on research performed by a consortium of expert investigators (including Dr. Levy’s team) from a pivotal trial sponsored by the National Institutes of Health.

This “closed loop,” or “artificial pancreas” technology is recommended for people with type 1 diabetes, and its use is growing in that population. The 2022 study by Dr. Levy and colleagues indicated that the technology may also benefit people with type 2 diabetes who require insulin, regardless of how they were taking insulin at baseline and whether they were also using other oral or injectable glucose-lowering medications.

“It’s not for everyone with type 2 diabetes but rather those already requiring insulin with or without other medications for type 2 diabetes. But I think this could represent an option for those who are struggling to keep their glucose levels in range,” says Dr. Levy, Professor of Medicine (Endocrinology, Diabetes and Bone Disease), and Director of the Mount Sinai Diabetes Center.

She presented data from the prospective, single-arm trial of 30 adults with type 2 diabetes in November 2022, during the virtual meeting of the Diabetes Technology Society. The study was sponsored by Tandem Diabetes Care, Inc., maker of the t:slim X2 insulin pump.

The participants had a mean age of 54 years, median diabetes duration of 14 years, and a mean hemoglobin A1C of 8.6 percent, considerably higher than the recommended target of less than 7 percent. They were a diverse group; with an enrollment consistent with what would be seen in people with type 2 diabetes based on race and ethnicity.

At baseline, just over half were using CGMs, 13 were using only basal insulin, and 17 were using both basal and pre-meal insulin. Among those 17 participants, 15 were using multiple daily injections, and two were using insulin pumps.

Most participants were also taking other medications, including sodium-glucose cotransporter-2 (SGLT2) inhibitors, glucagon-like peptide 1 (GLP-1) agonistsdipeptidyl peptidase 4 (DPP-4) inhibitors or a combination of more than one medication in addition to insulin as is typical for people with type 2 diabetes. They continued taking these adjunctive medications throughout the trial.

After six weeks, the mean time spent in the glucose range of 70-180 mg/dL (the target recommended range for blood sugars) was 71 percent, the mean time spent with levels greater than 180 mg/dL was 29 percent, and time spent above 250 mg/dL was just 2.9 percent. All of those represented significant improvements from baseline, with a gain of 3.6 hours per day in range and one fewer hour per day above 250 mg/dL.

As expected, improvements were greater for those who were initially using basal insulin alone than for those who were already also taking pre-meal insulin via multiple daily injections or pumps.

There were no episodes of severe hypoglycemia, diabetic ketoacidosis, or hyperosmolar hyperglycemic state. Time spent with glucose levels below 70 mg/dL dropped by 0.03 percent, a significant improvement, while time below 54 mg/dL, rare to begin with, remained the same.

There was some weight gain, from 81.9 kg to 83.2 kg, a common occurrence with improved glycemic control. Total daily insulin dose rose from 0.53U/kg to 64U/kg, also often seen with improvement in blood sugar control.

Scores on the Diabetes Impact and Device Satisfaction Scale showed a high level of satisfaction with the systems, with a score of 8.8 on a scale of 1 to 10.

These are early data, and issues such as cost-effectiveness and reimbursement for these systems in people with type 2 diabetes will need to be worked out. But, Dr. Levy believes even the protection from hypoglycemia alone argues in favor of their use.

“The risk of negative outcomes with hypoglycemia can be pronounced in people with longer duration of diabetes. Most of the study participants were in their 50s, with another 20 to 30 years to live, so we believe that improvement in glycemia at least for this younger population will lead to a more robust outcome and potentially better quality of life.”