Trial Outcomes & Findings for Diabetes Assistant (DiAs) Control-to-Range (CTR) Nocturnal Closed-Loop Camp Study (NCT NCT01973413)

Results Overview

Percent of time in a glucose target range of 70-150 mg/dl during camp study. Participants were randomized to either closed-loop (experimental) or sensor-augmented pump therapy (control) for the first night and then crossed over every other night to the other therapy over the course of the 5- to 6-day camp session. Thus there were \~60 nights of data for each intervention. However, data from closed-loop nights during which there were technical problems such as infusion set failure, sensor error \>20%, or pump failure resulting in a \>60-min interruption to closed-loop control were removed to allow for analysis of algorithm performance. Only nights with a minimum of 5 hours of closed-loop were included, and all glucose data were included in the analysis. For comparison, only data from nights during which sensor error was, \<20% with a minimum of 5 hours were included in the control group.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

32 participants

Primary outcome timeframe

6 nights

Results posted on

2015-04-24

Participant Flow

Participant milestones

Participant milestones
Measure	Inpatient Study The first phase of this study tested the feasibility of initializing the DiAs CTR system in a clinical research center. We tested the procedures that would occur with the camp studies, from consenting the subjects, obtaining morning glucose readings, initializing the sensor in the early afternoon, having some light activity in the evening, a bedtime snack, and initializing the closed-loop system within 30 minutes before they go to bed. We also tested how the system would perform using the same calibration and blood glucose monitoring that would be done at camp. In the inpatient study mimicked some camp activities by having the subjects have 20-30 minutes of aerobic activity in the afternoon and in the evening after dinner. The data from the inpatient studies was reviewed by the Data Safety Monitoring Board (DSMB) before we proceeded with the Phase 2 summer camp studies.	Camp Study The second phase of this proposal was the "in-camp" studies. The same health care providers that conducted the inpatient studies conducted the camp studies. They monitored all campers on closed-loop control in real-time. Participants were randomized to either closed-loop (experimental) or sensor-augmented therapy (control) for the first night and then crossed over every other night to the other therapy over the course of the 5- to 6-day camp session (i.e. on DiAs CTR every other night). Since participants were not always successfully completing a closed-loop control night, the pattern could not hold throughout the entire trial. Thus, there are numerous intervention sequences. Those assigned to DiAs closed-loop control were remotely monitored throughout the night. Those assigned to the control group were not monitored remotely overnight, but they were wearing Dexcom G4 Platinum sensors with active low and high sensor glucose alarms.
Overall Study STARTED	12	20
Overall Study COMPLETED	11	20
Overall Study NOT COMPLETED	1	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Diabetes Assistant (DiAs) Control-to-Range (CTR) Nocturnal Closed-Loop Camp Study

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Inpatient Study n=12 Participants The first phase of this study tested the feasibility of initializing the DiAs CTR system in a clinical research center. We tested the procedures that would occur with the camp studies, from consenting the subjects, obtaining morning glucose readings, initializing the sensor in the early afternoon, having some light activity in the evening, a bedtime snack, and initializing the closed-loop system within 30 minutes before they go to bed. We also tested how the system would perform using the same calibration and blood glucose monitoring that would be done at camp. In the inpatient study mimicked some camp activities by having the subjects have 20-30 minutes of aerobic activity in the afternoon and in the evening after dinner. The data from the inpatient studies was reviewed by the Data Safety Monitoring Board (DSMB) before we proceeded with the Phase 2 summer camp studies.	Camp Study n=20 Participants The second phase of this proposal was the "in-camp" studies. The same health care providers that conducted the inpatient studies conducted the camp studies. They monitored all campers on closed-loop control in real-time. Participants were randomized to either closed-loop (experimental) or sensor-augmented therapy (control) for the first night and then crossed over every other night to the other therapy over the course of the 5- to 6-day camp session (i.e. on DiAs CTR every other night). Since participants were not always successfully completing a closed-loop control night, the pattern could not hold throughout the entire trial. Thus, there are numerous intervention sequences. Those assigned to DiAs closed-loop control were remotely monitored throughout the night. Those assigned to the control group were not monitored remotely overnight, but they were wearing Dexcom G4 Platinum sensors with active low and high sensor glucose alarms.	Total n=32 Participants Total of all reporting groups
Age, Continuous	15.3 years STANDARD_DEVIATION 2.1 • n=5 Participants	15.3 years STANDARD_DEVIATION 2.9 • n=7 Participants	15.3 years STANDARD_DEVIATION 2.6 • n=5 Participants
Sex: Female, Male Female	6 Participants n=5 Participants	10 Participants n=7 Participants	16 Participants n=5 Participants
Sex: Female, Male Male	6 Participants n=5 Participants	10 Participants n=7 Participants	16 Participants n=5 Participants
HbA1c	8.7 percent of glycated hemoglobin STANDARD_DEVIATION 0.7 • n=5 Participants	8.1 percent of glycated hemoglobin STANDARD_DEVIATION 1.1 • n=7 Participants	8.4 percent of glycated hemoglobin STANDARD_DEVIATION 1.0 • n=5 Participants
Diabetes Duration	7.6 years STANDARD_DEVIATION 4.6 • n=5 Participants	5.6 years STANDARD_DEVIATION 3.5 • n=7 Participants	6.4 years STANDARD_DEVIATION 3.9 • n=5 Participants

PRIMARY outcome

Timeframe: 6 nights

Population: Data from OCL nights during which there were technical problems (infusion set failure, sensor error \>20%, pump failure with \>60-min interruption to closed-loop) were removed. Only nights with a minimum of 5h of OCL were included. For control, only data from nights where sensor error was \<20% with a minimum of 5h were included.

Percent of time in a glucose target range of 70-150 mg/dl during camp study. Participants were randomized to either closed-loop (experimental) or sensor-augmented pump therapy (control) for the first night and then crossed over every other night to the other therapy over the course of the 5- to 6-day camp session. Thus there were \~60 nights of data for each intervention. However, data from closed-loop nights during which there were technical problems such as infusion set failure, sensor error \>20%, or pump failure resulting in a \>60-min interruption to closed-loop control were removed to allow for analysis of algorithm performance. Only nights with a minimum of 5 hours of closed-loop were included, and all glucose data were included in the analysis. For comparison, only data from nights during which sensor error was, \<20% with a minimum of 5 hours were included in the control group.

Outcome measures

Outcome measures
Measure	Experimental: Closed-Loop Control n=41 Total Nights of Data Subjects will use the Diabetes Assistant (DiAs) and will wear a Tandem t:slim insulin pump and a Dexcom G4 Platinum sensor with active low and high sensor glucose alarms. Subjects will be remotely monitored throughout the night in real time. Diabetes Assistant (DiAs): The Control-to-Range (CTR) algorithm that will be used in DiAs will automatically adjusts insulin delivery in response to CGM values that have exceeded or are predicted to exceed the bounds of a pre-specified blood glucose range.	Control: Sensor-Augmented Pump Therapy n=39 Total Nights of Data Subjects will wear a Tandem t:slim insulin pump and a Dexcom G4 Platinum sensor with active low and high sensor glucose alarms. They will not use the Diabetes Assistant (DiAs) nor have remote monitoring.
Percent Time Near Normoglycemia	73 percentage of time Interval 50.0 to 89.0	52 percentage of time Interval 24.0 to 83.0

SECONDARY outcome

Timeframe: 6 nights

Population: Data from OCL nights during which there were technical problems (infusion set failure, sensor error \>20%, pump failure with \>60-min interruption to closed-loop) were removed. Only nights with a minimum of 5h of OCL were included. For control, only data from nights where sensor error was \<20% with a minimum of 5h were included.

Mean overnight glucose during camp study. Participants were randomized to either closed-loop (experimental) or sensor-augmented pump therapy (control) for the first night and then crossed over every other night to the other therapy over the course of the 5- to 6-day camp session. Thus there were \~60 nights of data for each intervention. However, data from closed-loop nights during which there were technical problems such as infusion set failure, sensor error \>20%, or pump failure resulting in a \>60-min interruption to closed-loop control were removed to allow for analysis of algorithm performance. Only nights with a minimum of 5 hours of closed-loop were included, and all glucose data were included in the analysis. For comparison, only data from nights during which sensor error was, \<20% with a minimum of 5 hours were included in the control group.

Outcome measures

Outcome measures
Measure	Experimental: Closed-Loop Control n=41 Total Nights Subjects will use the Diabetes Assistant (DiAs) and will wear a Tandem t:slim insulin pump and a Dexcom G4 Platinum sensor with active low and high sensor glucose alarms. Subjects will be remotely monitored throughout the night in real time. Diabetes Assistant (DiAs): The Control-to-Range (CTR) algorithm that will be used in DiAs will automatically adjusts insulin delivery in response to CGM values that have exceeded or are predicted to exceed the bounds of a pre-specified blood glucose range.	Control: Sensor-Augmented Pump Therapy n=39 Total Nights Subjects will wear a Tandem t:slim insulin pump and a Dexcom G4 Platinum sensor with active low and high sensor glucose alarms. They will not use the Diabetes Assistant (DiAs) nor have remote monitoring.
Overnight Glucose	140 mg/dL Standard Deviation 18	147 mg/dL Standard Deviation 36

SECONDARY outcome

Timeframe: 6 nights

Population: Data from OCL nights during which there were technical problems (infusion set failure, sensor error \>20%, pump failure with \>60-min interruption to closed-loop) were removed. Only nights with a minimum of 5h of OCL were included. For control, only data from nights where sensor error was \<20% with a minimum of 5h were included.

Number of nights with \>= 1 hypo- and hyperglycemic event occurring overnight during the camp study. Participants were randomized to either closed-loop (experimental) or sensor-augmented pump therapy (control) for the first night and then crossed over every other night to the other therapy over the course of the 5- to 6-day camp session. Thus there were \~60 nights of data for each intervention. However, data from closed-loop nights during which there were technical problems such as infusion set failure, sensor error \>20%, or pump failure resulting in a \>60-min interruption to closed-loop control were removed to allow for analysis of algorithm performance. Only nights with a minimum of 5 hours of closed-loop were included, and all glucose data were included in the analysis. For comparison, only data from nights during which sensor error was, \<20% with a minimum of 5 hours were included in the control group.

Outcome measures

Outcome measures
Measure	Experimental: Closed-Loop Control n=41 Total Number of Nights Subjects will use the Diabetes Assistant (DiAs) and will wear a Tandem t:slim insulin pump and a Dexcom G4 Platinum sensor with active low and high sensor glucose alarms. Subjects will be remotely monitored throughout the night in real time. Diabetes Assistant (DiAs): The Control-to-Range (CTR) algorithm that will be used in DiAs will automatically adjusts insulin delivery in response to CGM values that have exceeded or are predicted to exceed the bounds of a pre-specified blood glucose range.	Control: Sensor-Augmented Pump Therapy n=39 Total Number of Nights Subjects will wear a Tandem t:slim insulin pump and a Dexcom G4 Platinum sensor with active low and high sensor glucose alarms. They will not use the Diabetes Assistant (DiAs) nor have remote monitoring.
Glycemic Events Hyperglycemic (>250mg/dl)	4 nights with >= 1 event	4 nights with >= 1 event
Glycemic Events Hypoglycemic (<70mg/dl)	7 nights with >= 1 event	14 nights with >= 1 event

Adverse Events

Experimental: Closed-Loop Control

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Control: Sensor-Augmented Pump Therapy

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Marc Breton, PhD

Univeristy of VIrginia

Phone: 434-982-6484

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place