A device known as a bionic pancreas, which uses next-generation technology to automatically deliver insulin, was more effective at maintaining blood glucose (sugar) levels within normal range than standard-of-care management among people with type 1 diabetes, a new multicenter clinical trial has found. The trial, conducted partly at UT Health San Antonio and clinical partner University Health in San Antonio, was primarily funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health, and published Sept. 29 in the New England Journal of Medicine.

University Health’s Texas Diabetes Institute was one of five sites that enrolled children as study participants. Eighteen children ages 6-17, including 40% who are Hispanic, were recruited.

Minimal user input, more automation

Automated insulin delivery systems, also called artificial pancreas or closed-loop control systems, track a person’s blood glucose levels using a continuous glucose monitor and automatically deliver the hormone insulin when needed, using an insulin pump. These systems replace reliance on testing glucose level by fingerstick, on a continuous glucose monitor with separate insulin delivery through multiple daily injections, or on a pump without automation.

Compared to other available artificial pancreas technologies, the bionic pancreas requires minimal user input and provides more automation because the device’s algorithms continually adjust insulin doses automatically based on users’ needs. Users initialize the bionic pancreas by entering only their body weight into the device’s dosing software at the time of first use.

Users of the bionic pancreas also do not have to count carbohydrates, nor initiate doses of insulin to correct for high blood glucose. In addition, health care providers do not need to make periodic adjustments to the settings of the device.

“The bionic pancreas offers a turnkey solution to diabetes management,” said Rabab Jafri, MD, pediatric endocrinologist at the Texas Diabetes Institute and in the Division of Pediatric Endocrinology and Diabetes, part of the Joe R. and Teresa Lozano Long School of Medicine at UT Health San Antonio

“Only a minority of people with type 1 diabetes meet goals for therapy,” Jafri said. “This includes children. Under 15% of patients with type 1 diabetes in the pediatric age range are able to meet their glycated hemoglobin target of 7% and under.” Glycated hemoglobin, a test known by patients as “hemoglobin A1C,” is a measure of a person’s long-term blood glucose control.

The 13-week trial, conducted at University Health, UT Health San Antonio and 15 other clinical sites across the United States, enrolled 326 participants ages 6 to 79 years who had type 1 diabetes and had been using insulin for at least one year. Participants were randomly assigned to either a treatment group using the bionic pancreas device or a standard-of-care control group using their personal pre-study insulin delivery method. All participants in the control group were provided with a continuous glucose monitor, and nearly one-third of the control group were using commercially available artificial pancreas technology during the study.

In participants using the bionic pancreas, glycated hemoglobin improved from 7.9% to 7.3%, yet remained unchanged among the standard-of-care control group. The bionic pancreas group participants spent 11% more time, approximately 2.5 hours per day, within the targeted blood glucose range compared to the control group. These results were similar in youth and adult participants, and improvements in blood glucose control were greatest among participants who had higher blood glucose levels at the beginning of the study.

Insulin doses determined by bionic pancreas

“Children and adults alike with type 1 diabetes have been measuring carbs in their food and monitoring their glucose to make dosing decisions,” Jafri said. “It is an intense routine that patients are following repeatedly anywhere from four to 15 times a day. Extra factors such as exercise, certain medications, menses and illnesses add complexity to this routine by changing the amount of insulin the body needs at different times.

“Every dose of insulin is determined by the bionic pancreas during its wear. The dosing cycle is 288 times a day (every five minutes),” Jafri said. “The improved glycemic control achieved with less effort are great steps forward and should help many children for whom this mode of therapy will be suitable. Improved blood sugar control results in a decrease in the long-term complications of type 1 diabetes, which is especially important for children who may develop these complications at a relatively young age if their diabetes is not well controlled.”

Before coming to San Antonio, Jafri trained at Massachusetts General Hospital collaborating with the team at Boston University that developed the bionic pancreas system in collaboration with Harvard Medical School/Massachusetts General Hospital.

Hyperglycemia, or high blood glucose, caused by problems with insulin pump equipment, was the most frequently reported adverse event in the bionic pancreas group. The number of mild hypoglycemia events, or low blood glucose, was low and was not different between the groups. The frequency of severe hypoglycemia was not statistically different between the standard of care and bionic pancreas groups.

Additional details, including studies by San Antonio authors

Four companion papers were also published in Diabetes Technology and Therapeutics two of which provided more detailed results among the adult and youth participants. The third paper reported results from an extension study in which the participants from the standard-of-care control group switched to using the bionic pancreas for 13 weeks and experienced improvements in glucose control similar to the bionic pancreas group in the randomized trial. In the fourth paper, results showed that using the bionic pancreas with a faster-acting insulin in 114 adult participants improved glucose control as effectively as using the device with standard insulin.

Jafri and Jane Lynch, MD, professor of pediatric endocrinology at UT Health San Antonio and pediatric endocrinologist at the Texas Diabetes Institute, were writing group authors on two of those four companion papers that further explored the pediatric bionic pancreas outcomes.

“NIDDK’s decades-long investment in developing advanced technologies for diabetes management has reached another promising milestone and continues to provide significant return,” said NIDDK Director Griffin P. Rodgers, MD, MACP. “While we continue to search for a cure for type 1 diabetes, devices like the bionic pancreas can allow people to worry less about their blood-glucose levels and focus more on living their fullest, healthiest lives.”

The study is one of several pivotal trials funded by NIDDK to advance artificial pancreas technology and look at factors including safety, efficacy, user-friendliness, physical and emotional health of participants, and cost. To date, these trials have provided the important safety and efficacy data needed for regulatory review and licensure to make the technology commercially available. The Jaeb Center for Health Research in Tampa, Fla., served as coordinating center.