Three Way Crossover Closed Loop Study With Xeris Glucagon

Subjects will undergo three approximately 76 hour studies. During each of these intervention visits, subjects will wear an Omnipod to deliver insulin and a Dexcom G5 CGM to measure glucose. In the dual-hormone closed-loop study, participants will wear a second Omnipod filled with XeriSol™ glucagon. The first day of intervention visit will be a 12 hour inpatient visit with the subsequent time spent as an outpatient. The subject will come back to the research center on Day 4 in the morning to remove all devices. The blood glucose control system is called the Artificial Pancreas Controller (APC). During one of the studies, glucose will be controlled using the dual hormone mode. During another study, glucose will be controlled using the single hormone mode. The single and dual hormone modes of the APC controller determine insulin only and insulin with glucagon delivery rates based on proportional and derivative error and contain an exercise detection component. During the other study, glucose will be controlled using a predictive low glucose suspend (PLGS) mode. In the PLGS mode, the APC will be programmed with the subject's basal profile(s) which will be transmitted to the Omnipod Personal Diabetes Manager (PDM) and allow for boluses to be inputted by the subjects for meals and corrections using their typical carb ratios and correction factors. However, this system will have a safety feature to suspend insulin delivery when sensor glucose is predicted to go below a threshold. Treatment order will be randomized. Subjects will arrive at the clinic at approximately 7 or 8am for the inpatient visits. Subjects will eat breakfast and lunch at approximately 8:30am, noon and 6pm respectively. The dinner meal will be consumed while the subject is at home. Subjects will exercise on a treadmill for 45 minutes. Subjects will be discharged 9 hours after admission. The subject will then go home for the remainder of the study visit. Studies will be remotely monitored. Subjects will return to OHSU on Day 4 for removal of all devices. During each study, the subject will wear one subcutaneous DexcomTM G5 continuous glucose monitoring (CGM) system. The CGM system will provide sensed glucose data every 5 minutes. The accuracy of the sensed data will be obtained by reference measurements of capillary blood glucose. Sensed glucose data will be wirelessly transmitted via Bluetooth Low Energy (BTLE) from the Dexcom G5 transmitter to the Nexus 5 master controller every five minutes. The controller for all 3 modes is a Google Nexus 5 phone. The smart phone will wirelessly communicate via BTLE to an Omnipod through a PDM (Insulet Corp. ) for automated insulin delivery or in the case of dual-hormone AP, one used for automated insulin delivery and one for automated glucagon delivery. A physician or nurse practitioner will be present for study start-up, will be on campus for exercise on Day 1 and will be immediately available on call at all other times.