Conditions: Type 1 Diabetes Mellitus
Keywords: bionic pancreas type 1 diabetes
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 22
Healthy volunteers: no

Brief summary:
The study will consist of two study arms. Each arm will include a 24-96 hour outpatient run-in period prior to their exercise visit wearing the bi-hormonal bionic pancreas. In random order subjects will then complete two approximately 5-hour exercise visits, one wearing the bi-hormonal bionic pancreas and one wearing the insulin-only bionic pancreas.

Detailed description:
Twenty subjects will participate in two experimental periods. Each will include a 24-96 hour outpatient run-in period prior to their exercise visit wearing the bi-hormonal bionic pancreas. This will allow the bionic pancreas to adapt to their diabetes management needs. After the run-in period is complete, the subjects will participate in an exercise visit during which they will arrive fasting and remain fasted until the visit is completed. Subjects will walk on a treadmill for up to 1 hour at a comfortable walking pace. Plasma glucose (PG) measurements will be performed frequently. In one experimental period the bionic pancreas will remain in the bihormonal configuration and will deliver glucagon as needed during the exercise visit. In the other experimental period the glucagon will be replaced with a placebo during the exercise visit. The two experimental periods will be performed in random order. The study will be performed in single-blind fashion in that the participant will not know whether the bionic pancreas glucagon pump is filled with glucagon or placebo during the exercise visits. The outpatient run-in period will always be with the bi-hormonal bionic pancreas delivering glucagon.

Arms:
arm 1: Bihormonal bionic pancreas exercise visit - subjects will participate in the outpatient bihormonal bionic pancreas run in period, and will use the bihormonal bionic pancreas for their exercise visit at the end of the run in. The glucagon pump of the bionic pancreas will be filled with glucagon. arm 2: Insulin-only bionic pancreas exercise visit - Bihormonal bionic pancreas exercise visit - subjects will participate in the outpatient bihormonal bionic pancreas run in period, and will use the insulin-only bionic pancreas for their exercise visit at the end of the run in. The glucagon pump of the bionic pancreas will be filled with placebo (normal saline).

Interventions: intervention 1: Bihormonal Bionic Pancreas intervention 2: Insulin Only Bionic Pancreas intervention 3: Glucagon intervention 4: Placebo
Intervention descriptions: intervention 1: The glucagon pump will be filled with glucagon during the exercise visit intervention 2: The glucagon pump will be filled with placebo during the exercise visit, and the bionic pancreas will operate in an insulin only mode. intervention 3: Glucagon will be given according to the algorithm in the bihormonal bionic pancreas intervention 4: Placebo will be given instead of glucagon according to the algorithm in the insulin-only bionic pancreas

Protocol document:
Prot_SAP_000.pdf: