Three-month artificial pancreas study shows positive findings

An artificial pancreas system worn at home can improve blood glucose levels and reduce hypoglycemia in adults and children with type 1 diabetes over 12 weeks, a new study finds.
The findings were published online in the New England Journal of Medicine and presented at the 51st Annual Meeting of the European Association for the Study of Diabetes.
Two three-month multicentre studies were conducted by a research team led by the University of Cambridge’s Dr. Hood Thabit. These trials are the longest ever done using an artificial pancreas system that has achieved positive findings.
In the first study, 33 adults wore the closed-loop insulin-delivery system designed by the University of Cambridge, dubbed the “artificial beta cell”. In the second, 25 children and adolescents used the systems at night only. Control groups consisted of patients on insulin pump therapy.
The closed-loop system involves a patient having a CGM (continuous glucose monitor), insulin pump, and a program which calculates how much insulin is required in response to blood glucose readings.
In both studies, an insulin infusion rate was calculated by a control algorithm and sent wirelessly to the study insulin pump. In the adult study, a “hybrid closed-loop” approach was used which enabled volunteers to make their own decisions using the standard bolus calculator.
HbA1c levels
At the beginning of the study, the 33 adults had HbA1c levels ranging between 7.5-10 per cent. The children, aged six to 18, had baseline HbA1c levels below 10 per cent on insulin pump therapy.
The researchers measured the amount of time children kept their blood glucose results between 3.9 and 8.1 mmol/L (70 and 145 mg/dL).
On the closed loop system, children spent 60 per cent of the time within these glucose level ranges. This compared to just 34 per cent of the time for those on an insulin pump, but without the closed loop system.
For adults, the length of time was measured in which blood glucose levels were kept between a wider range of 3.9 and 10.0 mmol/L (70 and 180 mg/dL). Adults spent 68 per cent of the time within this threshold compared with 57 per cent of the time on the closed-loop system compared to insulin pump therapy.
Thabit told Medscape Medical News: “Our main aim was to be able to show that closed-loop application works in the day and night period, especially in the long term, and without supervision. We are now at a stage where we’ve shown that prolonged three-month, day/night use of closed-loop control in adults is feasible, and three-month overnight control in children is feasible.”
Thabit added that his team are currently working on developing the system for release in the United Kingdom. “At the moment, we’re looking at having a system available as soon as possible, as we’re using off-the-shelf items. The pump and [continuous glucose monitor] CGM are already available in Europen,” said Thabit.