None listed
Conditions
Brief summary
This study will evaluate the accuracy of an experimental CGM measuring glucose continuously in the immediate vicinity of subcutaneous insulin delivery in people with type 1 diabetes (T1D) on insulin pump therapy. Glucose sensor accuracy will be evaluated over a 7 day period as well as infusion site patency and tolerability of the experimental device. Participants will be changed to a study pump for the duration of the study. In addition to utilizing the study device in a free living state, all participants will also undergo two high carbohydrate mixed meal challenges to assess the performance and accuracy of the study device.
Interventions
Experimental combined insulin cannula and glucose sensor delivering basal and bolus insulin via insulin pump. A wearable device inserted subcutaneously (similar to current commercially available insulin lines and cannulas) which will be tested with the commercially available T:slim insulin pump.
This will involve a one week run in period where participants familiarise themselves with the T:slim pump in conjunction with current commercially available insulin lines and cannulas. This will be f
Experimental combined insulin cannula and glucose sensor delivering basal and bolus insulin via insulin pump. A wearable device inserted subcutaneously (similar to current commercially available insulin lines and cannulas) which will be tested with the commercially available T:slim insulin pump. This will involve a one week run in period where participants familiarise themselves with the T:slim pump in conjunction with current commercially available insulin lines and cannulas. This will be followed by seven days of wearing the experimental device with the T:slim pump. The experimental device will be inserted by a study nurse or doctor. Experimental device CGM data will be collected throughout the seven days. Mixed meal tests will be conducted on day 1 and day 7 of experimental device wear. These will involve the participants attending the study centre. They will be cannulated for frequent blood sampling. The mixed meal containing a large 100-120g carbohydrate component will be eaten and appropriate insulin bolus determined by the T:Slim bolus calculator administered. Settings in the T:Slim pump will be the same as their usual settings. Frequent blood sampling will assess BGL 15 minutely as well as samples taken for insulin assays for a period of 6hrs. Experimental device CGM accuracy will be compared with reference YSI BGL levels as well as commercially available Dexcom G5 CGM readings.
Sponsors
St Vincent's Hospital Melbourne
Study design
Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
21 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
1. T1D, of at least 6 months duration. 2. Age 21-75 3. Insulin pump usage at the time of screening and for at least 3 months prior to screening. 4. HbA1c between 5.8 and 10% 5. Willingness and ability to follow all study procedures and to attend all clinic visits.
Exclusion criteria
1. Chronic kidney disease as defined by estimated-GFR < 45 ml/min 2. Inadequately-treated proliferative diabetic retinopathy 3. Inability to read pump or CGM display due to reduced visual acuity 4. Presence of unstable ischaemic heart disease or myocardial infarction within the last 3 months. 5. Cerebrovascular disease causing permanent physical or cognitive limitation 6. Chronic liver disease with synthetic deficiency (defined as serum albumin of <3.3 g/dl, or serum total bilirubin exceeding 2.5 mg/dl) 7. Any active foot ulcer 8. Known active infection such as HIV or hepatitis 9. Active malignancy, except for basal or squamous cell skin cancer 10. Anaemia defined by HCT at least 4 percentage points below lower limit of the reference range 11. History of cardiac arrhythmia (note: PVC’s numbering < 6 per minute are not exclusionary) 12. Dementia 13. Schizophrenia or other untreated mental illness 14. Chronic substance abuse 15. Seizure disorder 16. Major surgical operation within 30 days prior to screening 17. Bleeding disorder, or treatment with anticoagulants 18. Allergy to Lispro insulin 19. Allergy to acrylate-based skin adhesives 20. Use of an investigational drug or device in the last 30 days 21. Female of childbearing potential who is pregnant or intending to become pregnant or breast-feeding, or is not using adequate contraceptive methods. 22. Diabetic ketoacidosis or major hypoglycemia within the last 6 months 23. Insulin resistance as defined by insulin requirement of more than 200 units per day 24. Use of glucose-lowering medications other than insulin 25. Need for uninterrupted treatment with acetaminophen 26. Any other physical or mental condition judged by the PI as being exclusionary.
Outcome results
None listed