Feasibility Study to Determine the Optimal Calibration Method for Glucose Sensors

Study Overview
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Brief Summary
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Two new glucose sensors (IR-Glucose Reader (Joanneum Research, Austria), IR-CGM (IMM, Germany)) will be investigated to determine the optimal calibration method in patients with type 1 diabetes

Detailed Description
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The subjects (Type 1 diabetes) will stay at the Clinical Research Centre for the whole period of the investigation (12 hours). Continuous blood glucose monitoring will be performed using the IR-Glucose Reader system and/or the IR-CGM system based on microdialysis. In parallel blood glucose measurements will be performed every 15 min as reference. The measurements of the sensors will be calibrated with different schemes and the difference between the calibrated glucose readings and the reference blood glucose values will be determined.

Official Title
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An Open, Single-centre, Non-controlled Feasibility Study to Determine the Optimal Calibration Method for Glucose Sensors Used for Continuous Glucose Monitoring in Patients With Type 1 Diabetes

Conditions
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Diabetes

Intervention / Treatment
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* Drug: Insulin dosing
* Device: Glucose sensors IR-Glucose Reader (Joanneum Research, Austria), IR-CGM (IMM, Germany)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Informed consent obtained after being advised of the nature of the study Male or female aged 18 to 75 years (both inclusive) The subject has Type 1 diabetes (as defined by WHO) for at least 24 months Body Mass Index (BMI) <= 35 kg/m2 Exclusion Criteria: Subject is actively enrolled in another clinical trial or took part in a study within 30 days Experienced recurrent severe hypoglycaemic unawareness (as judged by the investigator) A history of drug or alcohol dependence Positive result for HIV antibodies Positive result for Hepatitis B antigen or Hepatitis C antibodies Any other significant concomitant disease such as endocrine, cardiac, neurological, malignant, other pancreatic disease or uncontrolled hypertension as judged by the investigator Patient is pregnant, or breast feeding during the period of the study Patient donated blood in the last 3 months

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Insulin dosing and glucose sensors<br>To test the glucose sensors different levels of glycemia are needed. To provoke different glycemic levels the following intervention will be performed: Lunch (with fast glucose absorption characteristics) will be served. Up to 30 minutes after the usual insulin dosing time, the subjects will take his/her lunch dose of insulin adjusted to the chosen lunch plus additional approximately 25% (in the range of 0-50% according to the discretion of the Investigator) of insulin - in order to provoke moderate postprandial hypoglycaemia with glucose values < 70 mg/dl. | Drug: Insulin dosing<br> <br> * Other names: IR-CGM (IMM, Germany);Device: Glucose sensors IR-Glucose Reader (Joanneum Research, Austria), IR-CGM (IMM, Germany)<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| difference between calibrated measurements and reference | The calibrated sensor signals will be compared with the reference blood glucose values. The difference between the calibrated sensor signal and the reference values will be calculated (which corresponds to the error of the sensor signal) | 12 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| evaluate necessary run-in procedures by assessment of error over time | Once the difference between sensor signal and the reference values is calculated these values will be investigated by looking at the data over time which enables to detect a possible change of the difference. | 12 hours |