Comparison of an Artificial Pancreas Versus Threshold Low Glucose Suspend in Type 1 Diabetic Children

The study is an open randomized control trial preceded by a run-in period and follows a cross-over design.After inclusion, the therapy will be moved to sensor augmented pump therapy with a dedicated training to continuous glucose monitoring using study system (study CGM). During 2 to 3 weeks, the patient will use his/her usual insulin pump and the study CGM (run-in period). At the end of this period, the patient and the relative will be admitted in a parents'house or hotel/resort nearby the hospital for 65 hours to undergo the first interventional session. Admission will be at 17:00 Day 1. The investigator will connect wirelessly the study pump and CGM to the study platform DiAs and remote monitoring will be activated. Until 08:00 Day 2, insulin delivery will be managed in open-loop mode, i.e. insulin doses will be decided according to capillary glucose measurements. From 08:00 Day 2, one algorithm will be activated according to the randomization order, i.e. either the threshold low glucose suspend (TLGS) algorithm (threshold will be set at 70 mg/dl) or the closed-loop algorithm. Insulin delivery will then be managed in open-loop mode with activated TLGS or by the closed-loop algorithm until 08:00 Day 4. In both cases, meals will be of free content and taken around 09:00, 13:00, 17:00 and 20:00. Meal insulin doses will be managed according to pre-meal glucose level and CHO meal content in open-loop mode with TLGS, or according to DiAs bolus calculator suggestion in closed-loop mode. Patient and relative will be encouraged to move in parents'house or hotel/resort and surroundings between meals. The algorithm will be inactivated at 08:00 Day 4. The study pump will be removed and replaced by patient's usual pump. The patient and the relative will be released at 10:00 after breakfast. Study CGM will still be used at home for 2 to 4 weeks until the second interventional session. This session will be similar to the first one but the alternative algorithm will be activated. Patient will come back to pre-study insulin therapy from 08:00 Day 4 and be released at 10:00 when second session is completed.

Inclusion criteria

• Age from 7 to 12
• Puberty status at Prader 1
• Diabetes diagnosed according to WHO criteria since more than 1 year
• Fasting plasma C-peptide level <0.2 ng/ml for a fasting blood glucose level < 180 mg/dl
• At least one positiveness for plasma antibodies against pancreatic islets: IAA, IA2, GAD, ICA or ZnT8, since diagnosis of diabetes
• Treatment of diabetes by insulin pump since more than 6 months
• HbA1c level below 8.5%
• Trained in carbohydrate counting
• Lack of any associated disease or therapy (except insulin) affecting glucose metabolism
• Willingness to follow all study procedures
• Informed consent signed by patient and parent or legally responsible party
• Patient must be affiliated or beneficiary of a social medical insurance

Exclusion criteria

• Unwillingness of one parent or the legally responsible party to be present during all study procedures
• Expected use of acetaminophen-containing drugs
• Any disease or therapy (except insulin) affecting glucose metabolism during previous month
• Impaired cognitive or psychological abilities which may result in defective adherence to study procedures
• Active enrollment in another clinical trial or participation in a study within 30 days or participation in previous studies resulting in a cumulated annual income which would exceed 4500 €