NEJM: Artificial pancreas bests CGM in glucose control over 3 months

FreeStyle Navigator--Courtesy of Abbott

University of Cambridge researchers found that in a pair of similar studies, one in children and adolescents and the other in adults, that an artificial pancreas works better to control blood glucose levels in Type 1 diabetics than self-administration of insulin based on continuous glucose monitor (CGM) data.

"The data clearly demonstrate the benefits of the artificial pancreas when used over several months," Dr. Roman Hovorka, who developed the artificial pancreas and is director of research at Cambridge University's Metabolic Research Laboratories, said in a statement. "We have seen improved glucose control and reduced risk of unwanted low glucose levels."

Each study compared 3-month usage of a CGM alone use versus the same period with artificial pancreas use. Abbott ($ABT) provided the CGMs used and the closed-loop glucose system, also known as an artificial pancreas, was a combination of Abbott's FreeStyle Navigator 2 with the Dana Diabecare subcutaneous insulin infusion pump from South Korean company Sooil as controlled by the Florence D2A system.

In the adult study, hemoglobin levels were within the target range for an average of 11% more than during the control period. The mean overnight glucose level and the glycated hemoglobin level were in the target range more often with the artificial pancreas, rather than the CGM, but without an increase in daily insulin use. There was higher basal insulin delivery with the artificial pancreas, but lower bolus delivery.

In children and adolescents aged 6 to 16, the researchers found that the proportion of nocturnal time that glucose level was in the target range was higher by an average of 25% with the artificial pancreas rather than the CGM. The mean overnight glucose level also was significantly lower with the artificial pancreas than the CGM alone. This study was sponsored by the JDRF.

"The artificial pancreas could change my son's life, and the lives of so many others," said Susan Walls in a statement. She is the mother of 12-year-old Daniel Walls who participated in the study. "Daniel has absolutely no hypoglycaemia awareness at night. His blood glucose levels could be very low and he wouldn't wake up. The artificial pancreas could give me the peace of mind that I've been missing."

The study authors concluded, "We found that extended use of a closed-loop system at home over a period of 12 weeks during free daily living without close supervision is feasible in adults, children, and adolescents with Type 1 diabetes. Improvements in glucose control and reductions in the burden of hypoglycemia were observed."

- here is the JDRF announcement
- and here is the full study in the NEJM