Early Feasibility Study 2 of Outpatient Control-to-Range - Testing System Efficacy
An unblinded, randomized, cross-over design with each patient participating in two 40-hour outpatient admissions: (a) Experimental involving automated Control-to-Range (CTR) and (b) Control using Continuous Glucose Monitor (CGM)- augmented insulin pump treatment outside of a hospital based clinical research center. The principal goal is to validate a smart phone-based control-to-range (CTR) system for ambulatory use and to estimate the effect of CTR vs. sensor-augmented pump therapy, thereby providing justification for further larger home-based trials of CTR.
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||Early Feasibility Study 2 of Outpatient Control-to-Range - Testing System Efficacy|
- Safety, Low Blood Glucose Index (LBGI) [ Time Frame: 40 hours (x2 admissions) ] [ Designated as safety issue: Yes ]
The LBGI reflects the frequency and extent of hypoglycemic episodes and presents the results in "risk space." Thus the LBGI is a weighted average of the number of hypoglycemic readings, with progressively increasing weights as BG levels go down. The increase of the weights follows a risk function; thus the LBGI has been associated with risk for hypoglycemia and prediction of severe hypoglycemic episodes.
LBGI < 2.5 is associated with low risk of hypoglycemia, 2.5 < LBGI < 5 is associated with a moderate risk of hypoglycemia and LBGI > 5 is associated with a high risk of hypoglycemia.
- Safety, Frequency of Hypoglycemia [ Time Frame: 40 hours (x 2 admissions) ] [ Designated as safety issue: Yes ]Hypoglycemic episodes are defined as BG < 3.9mmol/L
- Efficacy, Time Spent in Target Range [ Time Frame: 40 hours (x2 admissions) ] [ Designated as safety issue: Yes ]Percentage of time in the target range of 3.9-10 mmol/L (70-180 mg/dL).
|Study Start Date:||October 2012|
|Study Completion Date:||January 2013|
|Primary Completion Date:||January 2013 (Final data collection date for primary outcome measure)|
Experimental: Experimental Involving Automated CTR
Closed-Loop Control: Insulin delivery will be controlled by the Diabetes Assistant (DiAs) system running in Control to Range (CTR) or in Safety Only mode. The subject will interact with the system through its Graphic User Interface (GUI). Subjects will not be allowed to administer correction boluses between meals and snacks as the DiAs will automatically be adjusting insulin to correct for hyperglycemia. The total doses recommended by the DiAs prior to meals and snacks includes the correction dose and Insulin on Board (IOB) calculated by the system.
Device: Diabetes Assistant (DiAs)
A medical platform that uses a smart-phone to connect to a continuous glucose sensor to insulin pump and run closed-loop control. The cell phone runs the Control to Range and is connected to work with the insulin pump and continuous glucose monitor to help keep the blood sugar in a desired range (80-180 mg/dL during the day) and help avoid hypoglycemia during the night.
No Intervention: CGM-Augmented Insulin Pump Treatment
Open Loop Control: Insulin delivery will be controlled by the Diabetes Assistant (DiAs) system running in open-loop mode. The subject will interact with the system through its Graphic User Interface (GUI). Subjects will be permitted to administer correction boluses at any time during the Control Admission, whether or not they are eating a scheduled meal or snack. DiAs will be initialized with the subject's typical insulin pump settings. The subject will be reminded that all treatment decisions should be based on fingerstick values and not on continuous glucose monitor (CGM) values.
The overall objective of this project is to sequentially test, validate, obtain regulatory approval for, and deploy at home, a closed-loop Control-to-Range (CTR) system for optimal blood glucose (BG) regulation in people with type 1 diabetes. The CTR system is comprised of two algorithmic layers: a Safety Supervision Module (SSM) and Insulin on Board Tracking and Safety Module (ITSM), and an automated Range Correction Module (RCM). Both modules will receive continuous glucose monitoring (CGM) and insulin delivery data. The SSM and ITSM will monitor the safety of the subject's continuous subcutaneous insulin infusion pump (CSII) to prevent hypoglycemia. The RCM will be responsible for optimizing BG control and mitigating postprandial hyperglycemic excursions through series of insulin boluses. To run CTR, we will use our wearable artificial pancreas platform, known as DiAs (Diabetes Assistant), which consists of a smart phone running CTR and connected to standard insulin delivery and CGM devices.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01714505
|United States, California|
|Sansum Diabetes Research Institute|
|Santa Barbara, California, United States, 93105|
|United States, Virginia|
|University of Virginia|
|Charlottesville, Virginia, United States, 22908|
|Principal Investigator:||Boris P. Kovatchev, Ph.D.||University of Virginia|