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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
Long-term implantable continuous glucose monitor in type 1 diabetes
Scientific title
Function of Implanted Glucose Sensor – High Definition Trial in type 1 diabetes
Secondary ID [1] 297042 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

This is a follow-up study.

Health condition
Health condition(s) or problem(s) studied:
Type 1 diabetes 311031 0
Condition category
Condition code
Metabolic and Endocrine 309672 309672 0 0

Study type
Description of intervention(s) / exposure
This trial is designed to evaluate data from a small group of participants to determine whether optimised sensor signal processing techniques with a new high definition sensor face have resulted in improved sensor performance. Additionally, reformulated device proteins may be assessed, and optimised manufacturing enhancements with the new high definition sensor face will be evaluated for both device tolerance and safety.

The investigational device is a subcutaneously implanted metal sensor about the size of a large USB that is designed to measure interstitial glucose levels. The sensor contains a small battery and a transmitter that wirelessly transmits data from the device to a handheld receiver and is stored in the receiver’s memory for later download and processing. It is fully implantable i.e. nothing is worn on the skin and will remain in-situ for a minimum of four and a half months, and up to a maximum of eight months. It will be implanted into the subcutaneous tissue of the lower abdomen by a qualified surgeon under local anaesthetic and light sedation. It will be removed following completion of the study.

Following implantation, the sensor requires no user interaction or maintenance, although the receiver needs to be kept close by to ensure that data packets are reliably recorded. The only maintenance required for the receiver is battery changes and download of receiver data.

Participants will undergo monthly clinic visits during the 8 months of implanted sensor wear. During each monthly visit, participants will undergo a supervised meal-driven glucose excursion where hourly capillary blood finger-prick and 15-minute venous blood glucose sampling will occur for up to 6 hours. Monthly blood samples will be obtained for chemistry, HbA1c, antibody testing (at certain months only) and retention.

Between clinical site visits, participants will carry a data logger receiver that records signal outputs from the implanted sensor (display shows date/time, but no glucose information), change the AAA batteries in the study receiver daily and confirm the receiver is receiving data, self-monitor blood glucose (SMBG) a minimum of 4 times per day, respond to texts or phone calls from study staff confirming the receiver is working with an appropriate date / time and record study activities in a participant diary.

Participants will also wear a provided commercially approved continuous glucose monitor (CGM) (Dexcom G5) during the study and participants will be trained on the use of the CGM by the study site. Participants will calibrate the CGM as required and this will enable real-time sensor data to participants. Participant data from the CGM (de-identified) will be downloaded during the monthly in-clinic visit.

Explantation of the sensor will occur following completion of their 8-month in-clinic visit, unless the 4-month or 6-month evaluation deem otherwise. The explantation procedure, in general, mimics the implantation procedure and is performed under local anaesthetic.
Intervention code [1] 313322 0
Treatment: Devices
Comparator / control treatment
Continuous glucose monitor values
Venous blood glucose values
Finger prick blood glucose measurements
Control group

Primary outcome [1] 318646 0
Investigational sensor MARD, compared with reference venous blood glucose measurements
Timepoint [1] 318646 0
During monthly in-clinic visits
Primary outcome [2] 318647 0
Safety of investigational sensor, measured through monitoring for anti-glucose oxidase and anti-catalase antibodies using serum assays
Timepoint [2] 318647 0
Screening, 7 days post-implant, 1st, 4th and 7th monthly clinic visit and 14 days post-explant
Secondary outcome [1] 365581 0
Investigational sensor MARD, compared with finger prick blood glucose measurements
Timepoint [1] 365581 0
At least 4x/day during at-home periods throughout the 8 month trial duration
Secondary outcome [2] 365582 0
Usability and tolerance of investigational sensor, measured through standardised participant questionnaires designed specifically for this study
Timepoint [2] 365582 0
1 day, 7 days and 14 days post-implant, monthly clinic visits and 14 days post-explant

Key inclusion criteria
* Type 1 diabetes mellitus for at least 5 years
* c-peptide <150pmol/L
* HbA1c <10%
* BMI less than or equal to 35kg/m2
Minimum age
18 Years
Maximum age
70 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
* Serious chronic illness
* Use of paracetamol during the trial

Study design
Purpose of the study
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Single group
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 12866 0
St Vincent's Hospital (Melbourne) Ltd - Fitzroy
Recruitment postcode(s) [1] 25341 0
3065 - Fitzroy

Funding & Sponsors
Funding source category [1] 301611 0
Commercial sector/Industry
Name [1] 301611 0
GlySens Incorporated
Address [1] 301611 0
3931 Sorrento Valley Blvd., Suite 110
San Diego, CA 92121
Country [1] 301611 0
United States of America
Primary sponsor type
St Vincent's Hospital Melbourne
41 Victoria Pde
Fitzroy VIC 3065
Secondary sponsor category [1] 301317 0
Name [1] 301317 0
Address [1] 301317 0
Country [1] 301317 0

Ethics approval
Ethics application status
Ethics committee name [1] 302338 0
St Vincents Hospital Melbourne HREC
Ethics committee address [1] 302338 0
Research Governance Unit
27 Victoria Pde
Fitzroy VIC 3065
Ethics committee country [1] 302338 0
Date submitted for ethics approval [1] 302338 0
Approval date [1] 302338 0
Ethics approval number [1] 302338 0
HREC 249/18

Brief summary
Achieving optimal glucose control in type 1 diabetes requires frequent monitoring of glucose which can be burdensome for many patients. The most common methods for self-monitoring glucose involve frequent "finger-pricking" or continuous glucose monitors inserted under the skin which last up to 1-2 weeks and require at least daily calibration with finger-pricks.

This investigational device is an implantable long-term glucose sensor that measures an individual's glucose levels continuously and sends data to a receiver outside the body. Following implantation, the sensor requires no user interaction, and the receiver only needs to be kept close by. The only maintenance required of the receiver is battery changes and data downloading.

This study aims to collect glucose information from the implanted sensor to optimise sensor signal processing and improve sensor performance.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 89874 0
Prof David O'Neal
Address 89874 0
St Vincent's Hospital Melbourne
41 Victoria Pde Fitzroy VIC 3065
Country 89874 0
Phone 89874 0
+61 3 9231 2211
Fax 89874 0
Email 89874 0
Contact person for public queries
Name 89875 0
Dr Melissa Lee
Address 89875 0
St Vincent's Hospital Melbourne
41 Victoria Pde Fitzroy VIC 3065
Country 89875 0
Phone 89875 0
+61 3 9231 2211
Fax 89875 0
Email 89875 0
Contact person for scientific queries
Name 89876 0
Dr Melissa Lee
Address 89876 0
St Vincent's Hospital Melbourne
41 Victoria Pde Fitzroy VIC 3065
Country 89876 0
Phone 89876 0
+61 3 9231 2211
Fax 89876 0
Email 89876 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
No other documents available
Summary results
No Results