Artificial Pancreas Proven Safe and Effective in Diabetics 6 Years and Older

Guillermo Arreaza-Rubin, MD

Results of a trial funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) could help redefine the treatment of type 1 diabetes in children.

The study found an approach using a closed-loop system of insulin delivery, which is often referred to as an artificial pancreas, was safe and effective for improving glycemic control in children as young as 6 years of age.

"Fewer than 1 in 5 children with type 1 diabetes are able to successfully keep their blood glucose in a healthy range with current treatment, which may have serious consequences on their long-term health and quality of life," said Guillermo Arreaza-Rubín, MD, director of NIDDK's Diabetes Technology Program and project scientist for the study, in a statement. "Earlier research showed that the system tested in this study was safe and effective for people ages 14 and older. This trial now shows us this system works in a real-world setting with younger children."

With the management of type 1 diabetes among younger patients a pressing issue and previous studies suggesting closed-loop control was safe and effective in children 14 and older, investigators sought to determine the safety and efficacy of the technology in a younger population. With this in mind, Arreaza-Rubin and a team of colleagues designed their study as a multicenter, randomized, open-label, parallel-group trial to be conducted at 4 pediatric diabetes centers in the US.

For inclusion in the trial, patients needed to be between 6-13 years of age, have a diagnosis of type 1 diabetes at least 1 year prior to enrollment, and be receiving treatment with insulin for at least 6 months. Participants were also required to have a bodyweight between 25-140 kg and have a total daily insulin dose of at least 10 units.

To assess the safety and effectiveness of the intervention, investigators chose the percentage of time that glucose level was in the target range of 70-180 mg per deciliter as the primary outcome of the trial. Patients included in the trial were enrolled between June 21, 2019 and August 30, 2019 and subsequently randomized in a 3:1 ratio to a closed-loop group or the study’s control arm.

Patients in the closed-loop arm of the trial were trained in the use of a closed-loop system consisting of a slim X2 insulin pump with Control-IQ Technology and a Dexcom G6 continuous glucose monitor. Patients in the control group used Dexcom G6 continuous glucose monitors. Investigators noted those using an insulin pump before the start of the trial continued to use their personal pumps.

As part of the trial’s protocol, all patients had trial visits at weeks 2, 8, and 16 and were contacted via telephone at weeks 1, 4, 6, 10, 12, and 14. Included as reportable adverse events in the trial were adverse events occurring in association with a trial device or procedure, severe hypoglycemia leading to the need for assistance because of altered consciousness, diabetic ketoacidosis as defined by Diabetes Control and Complications Trial criteria, and hyperglycemia with ketonemia for which a health care provider was contacted.

In total, 101 children underwent randomization in the trial. Of these, 78 were randomized into the closed-loop group and 23 were randomized into the control group. The mean duration of diabetes among the study population ranged from 1-12 years and the glycated hemoglobin levels at baseline ranged from 5.7-10.1.%. At the end of the trial, the median percentage of time in the closed-loop mode was 93% among patients in the closed-loop group and no episodes of diabetic ketoacidosis or severe hypoglycemia occurred in either group.

Results of the trial indicated the mean percentage of time with glucose level in target range increased from 53±17% at baseline to 67±10% in the closed-loop group and from 51±16% to 55±13% in the control group. Investigators pointed out this equated to a mean adjusted difference of 11 percentage points or 2.6 hours per day (95% CI, 7-14; P <.001). Investigators also noted the median percentage of time with a glucose level below 70 mg per deciliter was low in both groups—noting median percentages of 1.6% and 1.8% in the closed-loop and control groups, respectively.

"The improvement in blood glucose control in this study was impressive, especially during the overnight hours, letting parents and caregivers sleep better at night knowing their kids are safer," said trial protocol chair R. Paul Wadwa, MD, professor of pediatrics at the Barbara Davis Center for Childhood Diabetes at the University of Colorado, Aurora, in the aforementioned statement. "Artificial pancreas technology can mean fewer times children and their families have to stop everything to take care of their diabetes. Instead, kids can focus on being kids."

This study, “A Randomized Trial of Closed-Loop Control in Children with Type 1 Diabetes,” was published in the New England Journal of Medicine.