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Closing the Loop in Adults With Type 1 Diabetes in the Home Setting

This study has been completed.
Diabetes UK
Information provided by (Responsible Party):
Hood Thabit, University of Cambridge Identifier:
First received: September 20, 2011
Last updated: January 28, 2014
Last verified: January 2014
The main study objective is to compare real-time continuous subcutaneous glucose monitoring (CGM) combined with overnight automated closed-loop glucose control, and real-time CGM alone in the home setting.

Condition Intervention Phase
Type 1 Diabetes Mellitus
Other: Closed-loop
Other: Conventional insulin pump delivery
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: An Open-label, Three-centre, Randomised, Two-period, Crossover Study to Assess the Efficacy, Safety and Utility of Real-time Continuous Subcutaneous Glucose Monitoring Combined With Overnight Closed-loop Glucose Control in the Home Setting in Comparison With Real-time Continuous Subcutaneous Glucose Monitoring Alone in Adults With Type 1 Diabetes on Subcutaneous Insulin Infusion Pump Therapy

Resource links provided by NLM:

Further study details as provided by University of Cambridge:

Primary Outcome Measures:
  • Percentage of CGM (Continuous glucose monitoring) values in target (3.9 - 8.0 mmol/l). [ Time Frame: 4 weeks ]
    Participants will be assessed overnight (00:00 to 07:00) for 4 weeks in each arm.

Secondary Outcome Measures:
  • Percentage of CGM values below 3.9 mmol/l. [ Time Frame: 4 weeks ]
    Participants will be assessed overnight (00:00 to 07:00) for 4 weeks in each arm.

  • Time spent with glucose levels below 3.9 mmol/l and above 8.0 mmol/l, as recorded by CGM and other CGM-based metrics [ Time Frame: 4 weeks ]
    Participants will be assessed overnight (00:00 to 07:00) for 4 weeks in each arm.

  • Glycaemic control assessed by fructosamine and HbA1c [ Time Frame: 4 weeks ]
    Participants will be assessed for 4 weeks in each arm.

Enrollment: 24
Study Start Date: December 2012
Study Completion Date: January 2014
Primary Completion Date: December 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Closed loop (algorithm) Other: Closed-loop
Subcutaneous delivery of Novorapid insulin, dose calculated by control algorithm, based on continuous glucose sensor readings.
Other Name: Automated CL
Placebo Comparator: Open loop Other: Conventional insulin pump delivery
Subcutaneous delivery of Novorapid insulin according to usual pump regime

Detailed Description:

Achievement of tight glycaemic control in type 1 diabetes mellitus (T1D) using intensive insulin regimens, which has been shown to be important for the prevention of long term diabetes-related complications, is limited by a significantly increased risk of hypoglycaemia. The average patient with T1D suffers two symptomatic episodes of hypoglycaemia per week, and one episode of severe hypoglycaemia, defined as an event requiring assistance of another person to administer rescue treatment in the form of carbohydrate and/or glucagon, per year.Despite the rapid advancements in insulin pump technology and the ongoing development of more physiological insulin preparations, the currently available therapeutic regimens are still unable to achieve optimal glycaemic control.The emergence of continuous glucose monitoring (CGM) over the last decade, which enables users to view in real-time estimates of plasma glucose and receive alarms for impending hypo- or hyperglycaemia, thus facilitating appropriate changes in insulin therapy, is a major step towards improved diabetes monitoring.

The desirable goal is the development of an insulin delivery that is glucose responsive and the development of effective real time glucose monitoring should allow this. Glucose responsive insulin delivery should allow achievement of ideal glucose targets with less risk of hypoglycaemia. Closed-loop systems may provide a realistic treatment option for people with T1D. The research we are conducting at the University of Cambridge has been focused on developing a closed-loop system for overnight glucose control in patients with T1D. The studies that have been performed so far employ model predictive control (MPC) - this algorithm estimates patient-specific parameters from CGM measurements taken every 1 to 15 minutes and makes predictions of glucose excursions, which are then used to calculate basal insulin infusion rates. We hypothesize that overnight automated closed-loop glucose control in the home setting will be efficacious and safe compared to CGM alone, in T1D subjects on insulin pump treatment.


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Type 1 diabetes, as defined by WHO for at least 6 months or confirmed C−peptide negative.
  • On insulin pump therapy for at least 3 months

Exclusion Criteria:

  • Non−type 1 diabetes mellitus
  • Any physical/psychological disease likely to interfere with the study
  • Taking medication likely to interfere with interpretation of the results
  • Known/suspected allergy against insulin
  • Patients with clinically significant nephropathy, neuropathy or retinopathy as judged by the investigator
  • Ongoing severe recurrent hypoglycaemia as judged by the investigator.
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Please refer to this study by its identifier: NCT01440140

United Kingdom
Addenbrooke's Hospital
Cambridge, United Kingdom, CB2 0QQ
King's College London
London, United Kingdom, SE5 9RJ
Northern General Hospital
Sheffield, United Kingdom, S5 7AU
Sponsors and Collaborators
University of Cambridge
Diabetes UK
Principal Investigator: Roman Hovorka, PhD, MSc, BSc University of Cambridge
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Hood Thabit, Clinical Investigator, University of Cambridge Identifier: NCT01440140     History of Changes
Other Study ID Numbers: ANGELA03
Study First Received: September 20, 2011
Last Updated: January 28, 2014

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 1
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Autoimmune Diseases
Immune System Diseases
Insulin, Globin Zinc
Hypoglycemic Agents
Physiological Effects of Drugs processed this record on April 24, 2017