Trial Outcomes & Findings for Assessment of an Automatic Closed-loop Insulin Delivery System (NCT NCT02366767)

Results Overview

1. As measured by the number of events of plasma glucose values ≤ 50 mg/dL OR frequency of system alerts preceding a plasma glucose value of ≤ 50 mg/dL in all subjects 2. As measured by the number of events of system alerts of plasma glucose values \>300 mg/dL lasting for more than one hour in all subjects. 3. As measured by number of events of serum ketones \>3 mmol/L in all subjects 4. As measured by the number of events meeting the criteria for severe hypoglycemia, defined as hypoglycemic seizure, loss of consciousness or coma or an event requiring administration of glucagon or IV glucose in all subjects

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

21 participants

Primary outcome timeframe

6 days

Results posted on

2017-03-17

Participant Flow

Subjects for the Inpatients studies at Stanford were recruited from the Packard Diabetes clinics. Subjects for the camp studies were recruited from patients who had completed registration forms to attend camp. They were sent a letter describing the study and if they were interested they contacted us.

one subject enrolled in the closed-loop group had to leave camp after 24 hours and was replaced.

Participant milestones

Participant milestones
Measure	Automatic Closed-loop Insulin Delivery The closed-loop arm will consist of participants wearing a sensor and transmitter which transmits sensor glucose data. The algorithm determines insulin delivery rates and this is delivered in microboluses every 5 minutes Automatic closed-loop insulin delivery: Sensor transmit glucose data every 5 minutes to the control algorithm which adjusts insulin delivery every 5 minutes.	Control The subjects in the control arm will wear the 530G system using Enlite and MiniLink transmitter and threshold suspend. Control: Threshold suspend
Overall Study STARTED	11	10
Overall Study COMPLETED	10	10
Overall Study NOT COMPLETED	1	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Automatic Closed-loop Insulin Delivery The closed-loop arm will consist of participants wearing a sensor and transmitter which transmits sensor glucose data. The algorithm determines insulin delivery rates and this is delivered in microboluses every 5 minutes Automatic closed-loop insulin delivery: Sensor transmit glucose data every 5 minutes to the control algorithm which adjusts insulin delivery every 5 minutes.	Control The subjects in the control arm will wear the 530G system using Enlite and MiniLink transmitter and threshold suspend. Control: Threshold suspend
Overall Study left for home after 1 day at camp	1	0

Baseline Characteristics

Assessment of an Automatic Closed-loop Insulin Delivery System

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Automatic Closed-loop Insulin Delivery n=11 Participants The closed-loop arm will consist of participants wearing a sensor and transmitter which transmits sensor glucose data. The algorithm determines insulin delivery rates and this is delivered in microboluses every 5 minutes Automatic closed-loop insulin delivery: Sensor transmit glucose data every 5 minutes to the control algorithm which adjusts insulin delivery every 5 minutes.	Control n=10 Participants The subjects in the control arm will wear the 530G system using Enlite and MiniLink transmitter and threshold suspend. Control: Threshold suspend	Total n=21 Participants Total of all reporting groups
Age, Continuous	19.4 years STANDARD_DEVIATION 4.7 • n=5 Participants	17.7 years STANDARD_DEVIATION 2.2 • n=7 Participants	18.6 years STANDARD_DEVIATION 3.7 • n=5 Participants
Sex: Female, Male Female	6 Participants n=5 Participants	6 Participants n=7 Participants	12 Participants n=5 Participants
Sex: Female, Male Male	5 Participants n=5 Participants	4 Participants n=7 Participants	9 Participants n=5 Participants
Region of Enrollment United States	11 participants n=5 Participants	10 participants n=7 Participants	21 participants n=5 Participants
Hemoglobin A1c	8.5 % STANDARD_DEVIATION 1.9 • n=5 Participants	8.6 % STANDARD_DEVIATION 1.05 • n=7 Participants	8.6 % STANDARD_DEVIATION 1.5 • n=5 Participants

PRIMARY outcome

Timeframe: 6 days

Population: 10 subjects who completed study

1. As measured by the number of events of plasma glucose values ≤ 50 mg/dL OR frequency of system alerts preceding a plasma glucose value of ≤ 50 mg/dL in all subjects 2. As measured by the number of events of system alerts of plasma glucose values \>300 mg/dL lasting for more than one hour in all subjects. 3. As measured by number of events of serum ketones \>3 mmol/L in all subjects 4. As measured by the number of events meeting the criteria for severe hypoglycemia, defined as hypoglycemic seizure, loss of consciousness or coma or an event requiring administration of glucagon or IV glucose in all subjects

Outcome measures

Outcome measures
Measure	Automatic Closed-loop Insulin Delivery n=10 Participants The closed-loop arm will consist of participants wearing a sensor and transmitter which transmits sensor glucose data. The algorithm determines insulin delivery rates and this is delivered in microboluses every 5 minutes Automatic closed-loop insulin delivery: Sensor transmit glucose data every 5 minutes to the control algorithm which adjusts insulin delivery every 5 minutes.	Control n=10 Participants The subjects in the control arm will wear the 530G system using Enlite and MiniLink transmitter and threshold suspend. Control: Threshold suspend
Safety of Automatic Closed Loop Insulin Delivery System in Adolescents and Adults With Type 1 Diabetes Plasma glucose <50 mg/dL	9 Events	6 Events
Safety of Automatic Closed Loop Insulin Delivery System in Adolescents and Adults With Type 1 Diabetes Plasma glucose >300 mg/dL lasting more than 1 hour	0 Events	0 Events
Safety of Automatic Closed Loop Insulin Delivery System in Adolescents and Adults With Type 1 Diabetes Serum Ketones >3 mmol/L	0 Events	0 Events
Safety of Automatic Closed Loop Insulin Delivery System in Adolescents and Adults With Type 1 Diabetes Severe Hypoglycemia	0 Events	1 Events

SECONDARY outcome

Timeframe: 6 days

1. As measured by the system initiating and operating properly for at least 75% of the time for 75% of subjects. 2. As measure by the completion of study enrollment procedures and education on system use within 2 hours for 75% of the subjects.

Outcome measures

Outcome measures
Measure	Automatic Closed-loop Insulin Delivery n=10 Participants The closed-loop arm will consist of participants wearing a sensor and transmitter which transmits sensor glucose data. The algorithm determines insulin delivery rates and this is delivered in microboluses every 5 minutes Automatic closed-loop insulin delivery: Sensor transmit glucose data every 5 minutes to the control algorithm which adjusts insulin delivery every 5 minutes.	Control n=10 Participants The subjects in the control arm will wear the 530G system using Enlite and MiniLink transmitter and threshold suspend. Control: Threshold suspend
Feasibility of Using the Automatic Closed Loop Delivery System in Adolescents and Adults With Type 1 Diabetes Operational System >75% time	10 participants	10 participants
Feasibility of Using the Automatic Closed Loop Delivery System in Adolescents and Adults With Type 1 Diabetes Education completed within 2 hours	10 participants	10 participants

SECONDARY outcome

Timeframe: 6 days

Population: Including only sensor data where the daily median ARD \<15%.

As measured by overall mean sensor glucose percent time in range 70-180 mg/dL.

Outcome measures

Outcome measures
Measure	Automatic Closed-loop Insulin Delivery n=10 Participants The closed-loop arm will consist of participants wearing a sensor and transmitter which transmits sensor glucose data. The algorithm determines insulin delivery rates and this is delivered in microboluses every 5 minutes Automatic closed-loop insulin delivery: Sensor transmit glucose data every 5 minutes to the control algorithm which adjusts insulin delivery every 5 minutes.	Control n=10 Participants The subjects in the control arm will wear the 530G system using Enlite and MiniLink transmitter and threshold suspend. Control: Threshold suspend
Efficacy of Hybrid Closed-loop System in Comparison With Control	69.9 Percent time Standard Error 3.3	73.1 Percent time Standard Error 5.0

Adverse Events

Automatic Closed-loop Insulin Delivery

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Control

Serious events: 1 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Automatic Closed-loop Insulin Delivery n=11 participants at risk The closed-loop arm will consist of participants wearing a sensor and transmitter which transmits sensor glucose data. The algorithm determines insulin delivery rates and this is delivered in microboluses every 5 minutes Automatic closed-loop insulin delivery: Sensor transmit glucose data every 5 minutes to the control algorithm which adjusts insulin delivery every 5 minutes.	Control n=10 participants at risk The subjects in the control arm will wear the 530G system using Enlite and MiniLink transmitter and threshold suspend. Control: Threshold suspend
Endocrine disorders hypoglcyemic seizure	0.00% 0/11 • 6 days of camp	10.0% 1/10 • Number of events 1 • 6 days of camp

Other adverse events

Adverse event data not reported

Additional Information

Bruce Buckingham

Stanford School of Medicine

Phone: 650-725-9549

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place