Comparing Continuous With Flash Glucose Monitoring in Adults With Type 1 Diabetes (ALERTT1)

The present study wants to compare the Dexcom G6® continuous glucose monitoring (CGM) system (experimental group) with the FreeStyle Libre flash glucose monitoring (FGM) system (control group).

The ALERTT1 trial will have three phases: a baseline, study, and extension phase.

During the baseline phase, eligible patients will be screened for in- and exclusion criteria, wear a blinded Dexcom G6® for 28 days, together with their FreeStyle Libre FGM system, and receive a uniform education moment.

In the study phase, patients will be randomized into two groups (1:1): the experimental group will use an unblinded Dexcom G6® CGM for 6 months, the control group will keep using the FreeStyle Libre FGM system for 6 months. Before the 6 month time point is reached, patients in the control group will wear a blinded Dexcom G6® CGM for 28 days, together with their FreeStyle Libre FGM.

In the extension phase, patients in the initial control group will start using unblinded Dexcom G6® for 30 months. The initial experimental group will keep using the unblinded Dexcom G6® for the next 30 months.

Study Overview

• Status: Completed
• Conditions: Type 1 Diabetes Mellitus
• Intervention / Treatment: Device: Dexcom G6 CGM

• Study Type: Interventional
• Enrollment (Actual): 269
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Belgium
  • Aalst, Belgium, 9300
    • Onze-Lieve-vrouw Ziekenhuis Aalst
  • Bonheiden, Belgium, 2820
    • Imeldaziekenhuis Bonheiden
  • Jette, Belgium, 1090
    • University Hospital Brussels
  • Kortrijk, Belgium, 8500
    • AZ Groeninge Kortrijk
  • Leuven, Belgium, 3000
    • University Hospital Leuven
  • Wilrijk, Belgium, 2650
    • University Hospital Antwerp

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• signed ICF
• diagnosis of type 1 diabetes ≥6 months
• using FreeStyle Libre FGM system ≥6 months
• intensified insulin therapy/insulin pump therapy
• HbA1c ≤10%
• willing to wear the glucose monitoring device >80% of the time
• willing to download glucose monitoring data at regular intervals

Exclusion Criteria:

• non-type 1 diabetes participants or diagnosis <6 months
• participant with T1D not on insulin, or on non-intensified insulin therapy
• pregnancy or planning pregnancy within next 6 months
• severe cognitive dysfunction or other disease which makes sensor use difficult
• current treatment with drugs known to have significant interference with glucose metabolism, such as systemic corticosteroids, as judged by the investigator
• abnormal skin at the anticipated glucose sensor insertion sites (excessive hair, burn, inflammation, infection, rash, and/or tattoo)
• presence of concomitant pathology that might cause edema at the insertion sites (such as heart failure, liver failure, kidney failure defined as eGFR <30 mL/min [stage ≥4])
• beta-cell transplantation and c-peptide positive and/or under immunosuppressive therapy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Dexcom G6; Use a Dexcom G6 CGM for 36 months	Device: Dexcom G6 CGM; Use of Dexcom G6
No Intervention: FreeStyle Libre; Keep using their FreeStyle Libre for 6 months. Before the 6 month time point is reached, patients will wear a blinded Dexcom G6 for 28 days, together with their FreeStyle Libre. Cross-over to Dexcom G6 for 30 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference in time in range (70-180 mg/dL) between the control and experimental group	measured by Dexcom G6	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Between group difference in time in clinically important hypoglycemia (<54mg/dL)	measured by Dexcom G6	6 months
Between group difference of HbA1c		6 months
Between group difference in fear of hypoglycemia measured by the hypoglycemia fear survey		6 months
Between group difference in time in hypoglycemia (<70 mg/dL)	measured by Dexcom G6	6 months
Between group difference in time in target (70-140 mg/dL)	measured by Dexcom G6	6 months
Between group difference in time in hyperglycemia (>180 mg/dL)	measured by Dexcom G6	6 months
Between group difference in time in clinically important hyperglycemia (>250 mg/dL)	measured by Dexcom G6	6 months
Composite endpoint: between group difference in number of patients with HbA1c <7% without episodes of severe hypoglycemia		6 months
Between group difference in glycemic variability as measured by coefficient of variation [CV]	measured by Dexcom G6	6 months
Between group difference in glycemic variability as measured by standard deviation [SD]	measured by Dexcom G6	6 months
Between group difference in glycemic variability as measured by mean amplitude of glycemic excursions [MAGE]	measured by Dexcom G6	6 months
Between group difference in mean glucose concentration	measured by Dexcom G6	6 months
Between group difference in number of low glucose events (LGE)	LGE, measured by Dexcom G6, is defined as sensor glucose values ≤54 mg/dL for at least 15 minutes, preceded by at least 30 minutes with sensor glucose values >54 mg/dL	6 months
Between group difference in number of severe hypoglycemic episodes	reported by the participant	6 months
Between group difference in emotional distress due to diabetes measured by the problem areas in diabetes (PAID) questionnaire		6 months
Between group difference in hypoglycemia awareness measured by the Clarke hypoglycemia awareness survey		6 months
Between group difference in treatment satisfaction measured by the diabetes treatment satisfaction questionnaire (DTSQ)		6 months
Between group difference in general quality of life measured by the SF-36 questionnaire		6 months
Between group difference in number of patients having allergic reactions to the sensors	confirmed by a dermatologist	6 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of diabetes contacts which are not preplanned		6 months
Resource utilization (cost material, use of extra adhesives)		6 months
Number of severe adverse events		6 months
Hospitalizations for severe acute diabetes complications (hypoglycemia and ketoacidosis)		6 months
Work absenteeism due to diabetes		6 months
Number of patients who stop using the Dexcom G6 CGM and the reason to stop		6 months
Changes in time in range (70-180 mg/dL)	within-group change	36 months (extension phase)
Changes in time in target (70-140 mg/dL)	within-group change	36 months (extension phase)
Changes in time in hypoglycemia (<70 mg/dL)	within-group change	36 months (extension phase)
Changes in time in clinically important hypoglycemia (<54 mg/dL)	within-group change	36 months (extension phase)
Changes in time in hyperglycemia (>180 mg/dL)	within-group change	36 months (extension phase)
Changes in time in clinically important hyperglycemia (>250 mg/dL)	within-group change	36 months (extension phase)
Changes in time in glycemic variability, defined by coefficient of variation (CV)	within-group change	36 months (extension phase)
Changes in time in glycemic variability, defined by standard deviation (SD)	within-group change	36 months (extension phase)
Changes in time in glycemic variability, defined by mean amplitude of glycemic excursions (MAGE)	within-group change	36 months (extension phase)
Changes in time in number of low glucose events (LGE) (LGE is defined as sensor glucose values ≤54 mg/dL for at least 20 minutes, preceded by at least 30 minutes with sensor glucose values >54 mg/dL)	within-group change	36 months (extension phase)
Changes in HbA1c	within-group change	36 months (extension phase)
Changes in in emotional distress due to diabetes measured by the PAID questionnaire	within-group change	36 months (extension phase)
Changes in in hypoglycemia awareness measured by the Clarke hypoglycemia awareness survey	within-group change	36 months (extension phase)
Changes in treatment satisfaction measured by the DTSQ	within-group change	36 months (extension phase)
Changes in general quality of life measured by the SF-36 questionnaire	within-group change	36 months (extension phase)
Changes in in fear of hypoglycemia measured by the hypoglycemia fear survey	within-group change	36 months (extension phase)
Changes in hospitalizations for severe acute diabetes complications (hypoglycemia and ketoacidosis, expressed as admissions per patient year)	within-group change	36 months (extension phase)
Changes in work absenteeism (expressed as days of work absenteeism per patient year)	within-group change	36 months (extension phase)
Changes in number of severe hypoglycemic episodes (expressed as number of episodes per patient year)	within-group change	36 months (extension phase)
Number of patients who stop using the Dexcom G6® CGM and the reason to stop	within-group change	36 months (extension phase)

Collaborators and Investigators

• Sponsor: Universitaire Ziekenhuizen KU Leuven
• Collaborators: DexCom, Inc.

Publications and helpful links

General Publications

• Visser MM, Charleer S, Fieuws S, De Block C, Hilbrands R, Van Huffel L, Maes T, Vanhaverbeke G, Dirinck E, Myngheer N, Vercammen C, Nobels F, Keymeulen B, Mathieu C, Gillard P. Comparing real-time and intermittently scanned continuous glucose monitoring in adults with type 1 diabetes (ALERTT1): a 6-month, prospective, multicentre, randomised controlled trial. Lancet. 2021 Jun 12;397(10291):2275-2283. doi: 10.1016/S0140-6736(21)00789-3. Epub 2021 Jun 2.

Study record dates

Study Major Dates

• Study Start (Actual): January 29, 2019
• Primary Completion (Actual): October 1, 2020
• Study Completion (Actual): November 30, 2022

Study Registration Dates

• First Submitted: December 5, 2018
• First Submitted That Met QC Criteria: December 10, 2018
• First Posted (Actual): December 11, 2018

Study Record Updates

• Last Update Posted (Actual): December 21, 2022
• Last Update Submitted That Met QC Criteria: December 20, 2022
• Last Verified: December 1, 2022

More Information

Terms related to this study

• Keywords: continuous glucose monitoring; time in range; FreeStyle Libre; Dexcom G6; flash glucose monitoring
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Immune System Diseases; Autoimmune Diseases; Endocrine System Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 1
• Other Study ID Numbers: S61830

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Yes
• IPD Plan Description: Anonymous data can be shared with participating centers, based on research questions mentioned in this protocol or based on a new study protocol approved by the relevant ethical committees.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No