Day and Night Closed-loop in Young People With Type 1 Diabetes

The main study objective is to determine whether 24/7 automated closed-loop glucose control combined with low glucose feature will improve glucose control as measured by HbA1c. This is an open-label, multi-centre, multi-national, single-period, randomised, parallel group design study, involving a 6 month period of home study during which day and night glucose levels will be controlled either by a closed-loop system combined with low glucose feature (intervention group) or by insulin pump therapy alone (control group). It is expected that a total of up to 150 subjects (aiming for 130 randomised subjects) with type 1 diabetes will be recruited through paediatric outpatient diabetes clinics of the investigation centres. Participants will all be on subcutaneous insulin pump therapy. Subjects in the intervention group will have proven competencies both in the use of the study insulin pump and the study continuous glucose monitoring (CGM) device, and will receive appropriate training in the safe use of closed-loop insulin delivery system and low glucose feature. All subjects will have regular contact with the study team during the home study phase including 24/7 telephone support. The primary outcome is between group differences in HbA1c levels at 6 months post study arm initiation. Secondary outcomes are the time spent in the glucose target (3.9 to 10.0mmol/l; 70 to 180mg/dl), time spent with glucose levels above and below target, as recorded by CGM, and other CGM-based metrics. Safety evaluation comprises assessment of the frequency of severe hypoglycaemic episodes and diabetic ketoacidosis (DKA).