A Prospective Multicenter Evaluation of the Accuracy and Safety of an Implanted Continuous Glucose Sensor: The PRECISION Study.

Mark P Christiansen,Timothy S Bailey,Katherine S Tweden,Ron Brazg,Leslie J Klaff,Grace Carlson

doi:10.1089/dia.2019.0020

Abstract

Background: A prior study (PRECISE II) demonstrated that an implantable continuous glucose monitoring (CGM) system (Eversense® CGM System) provided accurate glucose readings through the 90-day sensor life with a favorable safety profile in participants with type 1 or type 2 diabetes (T1D, T2D). This study was performed to further characterize the accuracy of the system.Methods: PRECISION was a prospective multicenter study that evaluated the accuracy and safety of Eversense among adults with T1D or T2D through 90 days (NCT02647905). Accuracy measures included percentage system agreement and mean absolute relative difference (MARD) between Eversense and Yellow Springs Instrument reference measurements from 40 to 400 mg/dL. The primary safety endpoint was incidence of device-related or sensor insertion/removal procedure-related serious adverse events (SAEs) through 90 days. An updated glucose calculation algorithm was also applied to the sensor data from the PRECISE II study to evaluate consistency of accuracy results.Results: Thirty-five participants received the CGM system. Eighty-five percent of CGM values were within 15/15% of reference and the MARD value against reference was 9.6% (95% confidence interval [CI]: 8.9–10.4). All sensors were functional through day 90. No device- or procedure-related SAEs occurred. Application of the updated algorithm to PRECISE II sensor data resulted in 87% of readings within 15/15% of reference and an MARD value against reference of 8.5% (95% CI: 8.0%–9.1%).Conclusions: PRECISION corroborated prior accuracy and safety findings of the Eversense CGM System through the 90-day sensor life. The updated algorithm improved accuracy of measurements in PRECISE II.

Highlights

Real-time continuous glucose monitoring (CGM) has been shown to be superior in improving glycated hemoglobin (HbA1c) and reducing time spent in hypoglycemia compared with usual care with home blood glucose (BG) meters in individuals with type 1 diabetes (T1D)[1,2,3] and type 2 diabetes (T2D).[4,5] Prior studies have demonstrated that consistent use of CGM is required to effectively lower HbA1c and time in hypoglycemia; this improvement was negated when CGM was discontinued.[1,2] Despite the known benefits of consistent use of CGM, a recent survey of individuals who initiated CGM in the T1D Exchange registry found that 27% of patients discontinued use during the first a Mark P
An updated glucose calculation algorithm was applied to the sensor data from the PRECISE II study to evaluate consistency of accuracy results
Eighty-five percent of CGM values were within 15/ 15% of reference and the mean absolute relative difference (MARD) value against reference was 9.6% (95% confidence interval [confidence intervals (CIs)]: 8.9–10.4)

Summary

Introduction

Real-time continuous glucose monitoring (CGM) has been shown to be superior in improving glycated hemoglobin (HbA1c) and reducing time spent in hypoglycemia compared with usual care with home blood glucose (BG) meters in individuals with type 1 diabetes (T1D)[1,2,3] and type 2 diabetes (T2D).[4,5] Prior studies have demonstrated that consistent use of CGM is required to effectively lower HbA1c and time in hypoglycemia; this improvement was negated when CGM was discontinued.[1,2] Despite the known benefits of consistent use of CGM, a recent survey of individuals who initiated CGM in the T1D Exchange registry found that 27% of patients discontinued use during the first a Mark P. A prior study (PRECISE II) demonstrated that an implantable continuous glucose monitoring (CGM) system (EversenseÒ CGM System) provided accurate glucose readings through the 90-day sensor life with a favorable safety profile in participants with type 1 or type 2 diabetes (T1D, T2D). Methods: PRECISION was a prospective multicenter study that evaluated the accuracy and safety of Eversense among adults with T1D or T2D through 90 days (NCT02647905). An updated glucose calculation algorithm was applied to the sensor data from the PRECISE II study to evaluate consistency of accuracy results. Application of the updated algorithm to PRECISE II sensor data resulted in 87% of readings within 15/15% of reference and an MARD value against reference of 8.5% (95% CI: 8.0%–9.1%). Conclusions: PRECISION corroborated prior accuracy and safety findings of the Eversense CGM System through the 90-day sensor life. The updated algorithm improved accuracy of measurements in PRECISE II

Methods

Results

Conclusion