HbA1c Variation Study

To evaluate the relationship between glycated hemoglobin (HbA1c) and average glucose levels using continuous glucose monitoring.

Study Overview

• Status: Completed
• Conditions: Diabetes Mellitus
• Intervention / Treatment: Diagnostic test: HBA1c data and glucose levels

Detailed Description

This is a non-pivotal , non-randomized, single-arm, multi-center, prospective, non-significant risk study to evaluate the relationship between glycated hemoglobin (HbA1c) and average glucose levels. Up to approximately 600 subjects will be enrolled who will have fourteen (14) study visits over the course of approximately six (6) months. During each visit the subject will have blood samples drawn for documentation of their HbA1c level. Subjects will also be required to wear Professional FreeStyle Libre Flash Glucose Monitoring System(s) to record blood glucose levels through the duration of the study. During Visits 1 and 14, Venous sample for CBC, biochemistry, haemoglobinopathy screen, hematology, liver function and iron panels will be collected.

• Study Type: Observational
• Enrollment (Actual): 488

Contacts and Locations

Study Locations

• United Kingdom
  • Birmingham, United Kingdom, B9 5PU
    • University Hospital Birmingham
  • Bradford, United Kingdom, BD9 6RJ
    • Bradford Royal Infirmary
  • Derby, United Kingdom, DE22 3NE
    • Royal Derby Hospital
  • Edinburgh, United Kingdom, EH1 3EG
    • Edinburgh Royal Infirmary
  • Harrow, United Kingdom, HA1 3UJ
    • Northwick Park Hospital
  • Hull, United Kingdom, HU3 2JZ
    • Hull Royal Infirmary
  • Leeds, United Kingdom, LS9 7TF
    • St James University Hospital
  • Leicester, United Kingdom, LE1 5WW
    • Leicester General Hospital
  • Manchester, United Kingdom, M13 9WL
    • Manchester Royal Infirmary
  • Nottingham, United Kingdom, NG7 2UH
    • Nottingham Children's Hospital & Queen's Medical Centre
  • Reading, United Kingdom, RG1 5AN
    • Royal Berkshire Hospital
  • Sheffield, United Kingdom, S10 2SB
    • Northern General Hospital
  • Southall, United Kingdom, UB1 3HW
    • Ealing Hospital
  • Whitechapel, United Kingdom, E1 1FR
    • The Royal London Hospital
• United States
  • Florida
    • Miami Gardens, Florida, United States, 33169
      • Excellence Research and Medical
  • Idaho
    • Idaho Falls, Idaho, United States, 83404
      • Rocky Mountain Clinical Research
  • Montana
    • Billings, Montana, United States, 59101
      • Billings Clinic
  • New Mexico
    • Albuquerque, New Mexico, United States, 87109
      • Albuquerque Neuroscience Inc.
  • South Carolina
    • Anderson, South Carolina, United States, 29621
      • Anmed Health Internal Medicine Associates
  • Texas
    • Flower Mound, Texas, United States, 75028
      • Prime Revival Research Institute
  • Washington
    • Redmond, Washington, United States, 98052
      • Eastside Research Associates
    • Renton, Washington, United States, 98057
      • Rainier Clinical Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 4 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Subjects with type 1 or 2 diabetes.

Description

Inclusion Criteria:

1. Subject must have type 1 or type 2 diabetes.
2. Subject is at least 4 years old.
3. Point-of-care (POC) HbA1C of 3.0%-15.5% (9 mmol/mol - 146 mmol/mol)
4. Subject must be able to read and understand English.
5. In the investigator's opinion, the subject must be able to follow the instructions provided to him/her by the study site and perform all study tasks as specified by the protocol.
6. Subject must be available to participate in all study visits.
7. Subject must be willing and able to provide written signed and dated informed consent.
8. Subjects age 4 - 17: Parent or guardian must be willing and able to provide written signed and dated informed consent.

9. Subjects age 11 - 17 Subject must be willing and able to provide written signed and dated informed assent.

   Exclusion Criteria:

10. Subject is currently undergoing dialysis or planning to receive dialysis during the course of the study
11. History of blood transfusion in the last 3 months or planned blood transfusion during the course of the study.
12. Subject is currently planning to undergo a major medical intervention expected to significantly alter red cell life span, i.e. chemotherapy, major surgery requiring blood transfusions, etc.
13. Subject has known allergy to medical grade adhesive or isopropyl alcohol used to disinfect skin.
14. Subjects age 18 and older: Subject is known to be pregnant, attempting to conceive or is not willing and able to practice birth control during the study duration study (applicable to female subjects only). Subjects age 17 and younger: Subject is known to be pregnant at the time of study enrollment or is planning to become pregnant during the study (applicable to female subjects only).
15. Subject has extensive skin changes/diseases at the proposed application sites that could interfere with device placement or the accuracy of interstitial glucose measurements. Such conditions include, but are not limited to extensive psoriasis, recent burns or severe sunburn, extensive eczema, extensive scarring, dermatitis herpetiformis, skin lesions, redness, infection or edema.
16. Subject has a pacemaker or any other neurostimulators.
17. Subject has concomitant medical condition which, in the opinion of the investigator, could present a risk to the safety or welfare of the subject or study staff.
18. Subject is currently participating in another interventional clinical trial.
19. Subject is unsuitable for participation due to any other cause as determined by the Investigator.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Establish a relationship between laboratory-derived HbA1c and average glucose levels	This is an observational data collection study, where the goal is to gather data to establish the relationship between laboratory-derived HbA1c and average glucose levels.	six (6) months

Collaborators and Investigators

• Sponsor: Abbott Diabetes Care
• Investigators: Study Director: Shridhara A Karinka, PhD, Abbott Diabetes Care

Study record dates

Study Major Dates

• Study Start (Actual): December 20, 2021
• Primary Completion (Actual): December 30, 2023
• Study Completion (Actual): December 30, 2023

Study Registration Dates

• First Submitted: December 20, 2021
• First Submitted That Met QC Criteria: December 29, 2021
• First Posted (Actual): January 13, 2022

Study Record Updates

• Last Update Posted (Actual): May 25, 2025
• Last Update Submitted That Met QC Criteria: May 23, 2025
• Last Verified: May 1, 2025

More Information

Terms related to this study

• Keywords: Professional FreeStyle Libre Flash Glucose Monitoring System; HBA1C
• Other Study ID Numbers: ADC-US-RES-21212

Drug and device information, study documents

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