Closed-loop Control of Glucose Levels (Artificial Pancreas) for 60 Hours in Adults With Type 1 Diabetes

An Open-label, Randomized, Three-way, Cross-over Study to Assess the Efficacy of Single-hormone Closed-loop Strategy, Dual-hormone Closed-loop Strategy and Conventional Insulin Pump Therapy in Regulating Glucose Levels During 60 Hours in Free-living Conditions in Patients With Type 1 Diabetes

Closed-loop strategy is composed of three components: glucose sensor to read glucose levels, insulin pump to infuse insulin and a dosing mathematical algorithm to decide on the required insulin dosages based on the sensor's readings. A dual-hormone closed-loop strategy would regulate glucose levels through the infusion of two hormones: insulin and glucagon.

The main objective of this project is to compare the efficacy of single-hormone closed-loop strategy, dual-hormone closed-loop strategy and conventional insulin pump therapy to regulate glucose levels in a 60-hours in non-standardized conditions in adults with type 1 diabetes.

The investigators hypothesized that 1) Controlling glucose levels using single- or dual-hormone CLS is feasible in free-living conditions for long period of time (60 hours); 2) Dual-hormone CLS is superior to single-hormone CLS as assessed by reducing time spent in hypoglycemic range; 3) Both single-hormone and dual-hormone CLS are superior to conventional pump therapy.

Inclusion Criteria:

• Males and females ≥ 18 years of old.
• Clinical diagnosis of type 1 diabetes for at least one year.
• The subject will have been on insulin pump therapy for at least 3 months.
• HbA1c ≤ 12%.

Exclusion Criteria:

• Clinically significant nephropathy, neuropathy or retinopathy as judged by the investigator.
• Recent (< 6 months) acute macrovascular event e.g. acute coronary syndrome or cardiac surgery.
• History of pheochromocytoma or insulinoma (glucagon could induce an hormonal response of these tumors)
• Beta-blockers at high dose based on investigator's evaluation of dosage interference with glucagon (glucagon can modify effect of beta-blockers, mostly evident at very high doses)
• Chronic indometacin treatment (can prevent glucagon effect on liver thus its ability to raise glucose)
• Warfarin chronic treatment if INR monitoring cannot be evaluated (can increase the risk of bleeding)
• Anticholinergic drug (risk of interaction)
• Pregnancy.
• Severe hypoglycemic episode within two weeks of screening.
• Current use of glucocorticoid medication (except low stable dose and inhaled steroids).
• Known or suspected allergy to the trial products or meal contents (gluten free menus will be available).
• Other serious medical illness likely to interfere with study participation or with the ability to complete the trial by the judgment of the investigator (e.g. need for major revision of carbohydrate counting).
• Anticipating a significant change in exercise regimen between admissions (i.e. starting or stopping an organized sport).
• Failure to comply with team's recommendations (e.g. not willing to eat meals/snacks, not willing to change pump parameters, etc).
• Treatments that could interfere with glucagon