Feasibility Study of a Modular Control to Range System in Type 1 Diabetes Mellitus
Condition: Type 1 Diabetes Mellitus
MeSH terms: Diabetes Mellitus; Diabetes Mellitus, Type 1
Study type: Interventional

Summary: 
      In this protocol the investigators plan to demonstrate the feasibility of a modular insulin
      management system based on continuous glucose monitoring and targeted towards the avoidance
      of hypoglycemic and prolonged hyperglycemic episodes (i.e. control to range). The protocol is
      designed to challenge the insulin management system with meals and mild exercise, so as to
      demonstrate its capacity to avoid large glucose excursion with changing metabolic state. This
      system is designed to both

        -  monitor the meal boluses of the patient and correct it in case of observed/predicted
           under insulinization (avoidance of prolonged hyperglycemia), based on a coarse and
           subjective knowledge of the meal amount, a precise understanding of the subject's day to
           day insulin treatment, continuous glucose monitoring, and past insulin injections;

        -  predict and avoid hypoglycemic events, based on continuous glucose reading and past
           insulin injection.

      The investigators plan to enroll 12 adult Type 1 Diabetes Mellitus (T1DM) patients (expected
      retention 10/12) and compare glucose control performances under two treatments: standard vs.
      the new insulin management system. The protocol will include a total of 6 admissions per
      subject (4 out-patients and 2 in-patients): screening, effort test, CGM insertion 1,
      inpatient 1, CGM insertion 2, and inpatient 2. During the 24h inpatient admissions, the
      patients will be challenged with 30 minutes of mild exercise and 3 meals, insulin coverage of
      these events will vary depending on the chosen treatment, each subject will be exposed to
      both studied treatments (repeated measure design).The order of treatment during the inpatient
      admissions will be randomized.
    


Intervention name(s): Closed Loop Control (CLC); Open Loop
Intervention type(s): Device; Device
Intervention description(s): In this study, the researchers compared the management of diabetes during physical activity and meals with the closed-loop system developed at the University of Virginia. This Control to Range System uses two DexCom Seven Continuous Glucose Monitor, a computer containing an investigational control algorithm (well-defined instructions that are expressed in mathematical equations), and an OmniPod Insulin Management System, a portable subcutaneous (under the skin) insulin pump. During the closed-loop admission, the computer used CGM values to make recommendations of insulin treatment based on the algorithms.; This admission was to assess the subjects' level of glucose control and created a base to compare the performance of the closed-loop system. Subjects monitored their own blood glucose values and administer their basal/bolus as they would at home. Subjects use their own pump. Otherwise, the admission remained the same as in the closed-loop admission (i.e. meals, exercise, etc...).
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Supportive Care