This study will compare two different models of a wearable bionic pancreas device (the iPhone-based bionic pancreas vs. the iLet bionic pancreas) in adult participant with type 1 diabetes. Both bionic pancreas devices measure glucose levels every five minutes and then give insulin and/or glucagon automatically to regulate the blood glucose (BG).
The iPhone bionic pancreas has been used in earlier studies, during which volunteers used the system for up to 11 days at a time while living their normal lives at home and work. The iLet bionic pancreas has never been tested in humans. In this new study, volunteers will participate in a training visit to learn how both devices work. They will then use the iPhone-based BP for 1 day and the iLet BP for 1 day in random order using Lilly glucagon. They will then use the iLet BP for one additional day using Xeris Xerisol glucagon (a stable formulation of human glucagon). A custom infusion set is required for this bihormonal system, to prevent future consumers from being able to accidentally swap their insulin and glucagon reservoirs and infusion sets, which could be potentially fatal. Previous experiments have demonstrated flaws in the infusion set design, requiring human experiments to be suspended and modifications to the infusion set be made. We believe the current infusion set has addressed these flaws by incorporating an anti-coring heel and a tri-beveled needle, and the infusion set sub-study is designed to isolate and study the infusion set function before further experiments using the iLet BP are conducted.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
20
An experimental device composed of three parts: a continuous glucose monitor, control algorithms running on an iPhone, and drug delivery using Tandem insulin pumps
An experimental device that combines the functions of the iPhone-based bionic pancreas into one device.
A stabilized formulation of human glucagon in a solvent based primarily composed of dimethyl sulfoxide (DMSO) that has prolonged stability and can be used for multiple days in a pump
MGH Diabetes Research Center
Boston, Massachusetts, United States
Average Percent Dose Amounts Calculated by the Bionic Pancreas Control Algorithm That Are Successfully Delivered by the Pump (Aggregate of Both Insulin and Glucagon Doses)
Average percent dose amounts calculated by the bionic pancreas control algorithm that are successfully delivered by the pump (aggregate of both insulin and glucagon doses) - primary outcome for iPhone-based BP using Lilly glucagon vs. iLet BP using Lilly glucagon
Time frame: 8 hours
Average Percent Dose Amounts Calculated by the Bionic Pancreas Control Algorithm That Are Successfully Delivered by the Pump (Glucagon Doses).
Average percent dose amounts calculated by the bionic pancreas control algorithm that are successfully delivered by the pump (glucagon doses) - - primary outcome for iLet BP using Lilly glucagon vs. iLet BP using Xeris Xerisol glucagon
Time frame: 8 hours
Insulin Area Under the Curve in the 3.5 Hours Following the Insulin Bolus
This applies only to the infusion set sub-study
Time frame: 3.5 hours following insulin bolus
Average Continuous Glucose Monitor (CGM) Glucose
The average glucose according to continuous glucose monitor readings. This only applies to the iPhone vs. iLet BP experiments.
Time frame: 8 hours
Percentage of Time in Each of the Following Ranges: < 50 mg/dl, < 60 mg/dl, <70 mg/dl, 70-120 mg/dl, 70-180 mg/dl, >180 mg/dl, >250 mg/dl
Percentage of time subjects spent in each of these ranges based on continuous glucose monitor readings. This only applies to the iPhone vs iLet BP visits.
Time frame: 8 hours
Number of Subjects With Mean CGM Glucose < 154 mg/dl
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
An aqueous formulation of human glucagon with limited stability that must be changed daily
The infusion set sub-study will be studying the experimental iLet infusion set in a cross-over with the Contact Detach infusion set. These visits will be conducted separately from the iPhone and iLet BP visits.
The infusion set sub-study will be studying the experimental iLet infusion set in a cross-over with the Contact Detach infusion set. These visits will be conducted separately from the iPhone and iLet BP visits.
The number of subjects who achieved a mean CGM glucose \< 154 mg/dl, which correlates to an estimated hemoglobin a1c of 7%, which is the ADA goal for therapy. This applies only to the iPhone vs iLet BP experiments
Time frame: 8 hours
Number of Severe Hypoglycemic Events (Subject Unable to Self-treat, Requiring the Assistance of Another Person)
The number of severe hypoglycemic events subjects experience. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Average Percent Insulin Dose Amounts Calculated by the Bionic Pancreas Control Algorithm That Are Successfully Delivered by the Pump.
The average percentage of successfully delivered insulin doses. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Average Percent Glucagon Dose Amounts Calculated by the Bionic Pancreas Control Algorithm That Are Successfully Delivered by the Pump.
The average percentage of successfully delivered glucagon doses. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Average Percent Insulin Dose Amounts Successfully Issued to the Pump by the Bionic Pancreas Control Algorithm That Are Successfully Delivered by the Pump.
The average percentage of successfully issued insulin doses that are then delivered successfully by the pump. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Average Percent Glucagon Dose Amounts Successfully Issued to the Pump by the Bionic Pancreas Control Algorithm That a Successfully Delivered by the Pump.
The average percentage of successfully issued glucagon doses that are then delivered successfully by the pump. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Average Percent of 5 Minute Steps During Which the Bionic Pancreas is Functioning Nominally in All Respects Based on Real-time CGM Data (New CGM Glucose Reading Captured, Dose Calculated, Dose Issued to Pumps
The percentage of time (measured in 5 minute "steps") that the bionic pancreas is working, indicated by the presence of a CGM reading, a successful dose calculation and successful issuing of a dose. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Average Percent of 5 Minute Steps During Which the Bionic Pancreas is Functioning Nominally With or Without a New CGM Glucose Reading Captured (Dose Calculated, Dose Issued to Pumps).
The percentage of time (measured in 5 minute "steps") that the bionic pancreas is working even without a CGM reading being present, indicated by a successful dose calculation and successful issuing of a dose. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
CGM Reliability Index, Calculated as Percent of Possible Values Actually Recorded by CGM.
A measure of CGM reliability, indicating the percentage of values the CGM displayed out of the total values it should have displayed in that time. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Glucagon Total Delivery Per kg of Body Mass.
The average total glucagon delivered by the bionic pancreas. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Insulin Total Delivery Per kg of Body Mass.
The average total insulin delivered by the bionic pancreas. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Number of Episodes of Symptomatic Hypoglycemia.
Number of time subjects experienced symptoms of hypoglycemia and reported that to study staff. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Total Grams of Carbohydrate Taken for Hypoglycemia.
The total grams of carbohydrates given to subjects for treatment of hypoglycemia. This applies only to the iPhone vs iLet BP experiments.
Time frame: 8 hours
Difference in Mean Nausea From VAS During the Study
This applies only the iPhone vs. iLet BP experiments. Subjects were given a visual analog scale measuring 100 mm and asked to draw a line to indicate their level of nausea at timepoints during the study with 100 being the "worst possible nausea" and 0 being "no nausea".
Time frame: 8 hours
Average Insulin Infusion Site Pain From VAS
This applies to the iPhone vs. iLet BP experiments and the infusion set sub-study experiments. Subjects were given a visual analog scale measuring 100 mm and asked to draw a line to indicate their level of pain at timepoints during the study with 100 being the "worst possible pain" and 0 being "no pain".
Time frame: 8 hours
Difference in Local Erythema and Edema According to the Draize Scale
This applies to the iPhone vs. iLet BP experiments and the infusion set sub-study experiments. The draize scale assess erythema, eschar and edema using a score from 0-4, with 4 meaning a worse outcome.
Time frame: 8 hours
Number of Unscheduled Infusion Set Replacements.
This applies to the iPhone vs. iLet BP experiments and the infusion set sub-study experiments.
Time frame: 8 hours
Number of Unscheduled CGM Sensor Changes.
This applies only to the iPhone vs. iLet BP experiments
Time frame: 8 hours
Insulin Area Under the Curve During the Initial 90 Minute Fasted Period
This applies only to the infusion set sub-study
Time frame: 8 hours
Mean Insulin Levels During the Initial 90 Minute Fasted Period
This applies only to the infusion set sub-study
Time frame: 8 hours
Difference Between Insulin Levels at Baseline and at 90 Minutes
This applies only to the infusion set sub-study
Time frame: 8 hours
Tmax After the Insulin Dose
This applies only to the infusion set sub-study
Time frame: 8 hours
T 1/2 Max After the Insulin Dose
This applies only to the infusion set sub-study
Time frame: 8 hours
C Max After the Insulin Dose
This applies only to the infusion set sub-study
Time frame: 8 hours
AUC in the First 30 Minutes After the Insulin Dose
This applies only to the infusion set sub-study
Time frame: 8 hours
AUC in the First 60 Minutes After the Insulin Dose
This applies only to the infusion set sub-study
Time frame: 8 hours
AUC in the First 90 Minutes After the Insulin Dose
This applies only to the infusion set sub-study
Time frame: 8 hours
Terminal Half Life After the Insulin Dose
This applies only to the infusion set sub-study
Time frame: 8 hours
Difference Between the Fasted PG Value and the PG Value at 90 Minutes
This applies only to the infusion set sub-study
Time frame: Baseline Fasted State and 90 Minutes
Difference in the PG Prior to the Meal and Peak Post-prandial Glucose
This applies only to the infusion set sub-study
Time frame: Pre-meal PG value and peak PG value during the 3.5 hours following the meal.
PG AUC in the 3.5 Hours Following the Meal
This applies only to the infusion set sub-study
Time frame: 3.5 hours following the meal