Orlando, Florida - When adolescents and adults with type 1 diabetes (T1D) used a new continuous glucose monitoring (CGM) device containing a sensor that can remain implanted in the arm for up to 180 days, the system provided accurate glucose measurement with no major side effects, according to the study, “First Assessment of the Performance of an Implantable CGM System through 180 Days in a Primarily Adolescent Population with Type 1 Diabetes,” presented at the American Diabetes Association’s® (ADA’s) 78th Scientific Sessions® at the Orange County Convention Center.
Continuous glucose monitoring allows people with T1D to constantly measure whether their glucose levels are going up or down and the rate at which the changes are occurring. Current CGM devices require re-insertion of the monitoring sensor every one or two weeks using a procedure that can be uncomfortable or painful. The Eversense® XL CGM system uses a fully implantable sensor that resides under the skin for up to six months in the subcutaneous tissue layer of the upper arm. The system also incorporates a lightweight, water-resistant transmitter, which is worn on the skin over the sensor and facilitates the glucose reading calculations that are displayed via a mobile app on iOS and Android devices and can also be displayed on an Apple Watch. The transmitter can be removed and put back in place over the sensor at the discretion of the user, and it provides an “on-body” vibratory alert for low- and high-glucose values.
Two previous studies have shown the Eversense technology to be safe and effective, including a six-month European trial published in 2017 (PRECISE) and a three-month American study published earlier this year (PRECISE II). Both studies showed that the device maintained accuracy. The current study is the first to investigate the safety and efficacy of the Eversense XL CGM for 180 days in a primarily adolescent population with T1D.
The study was conducted in Canada and enrolled 36 patients—30 adolescents (average age 14 years) and six adults (average age 32 years)—with T1D. Most of the participants (64 percent) had previously used a CGM device. For insulin delivery, 32 of the 36 patients used an insulin pump, while four used multiple daily insulin injections. Study participants had a sensor implanted in the upper arm during a simple, in-office procedure in the diabetes clinic. The adults were inserted with two sensors and adolescents were inserted with one sensor. Participants were then evaluated each month with a full-day clinic visit during which multiple blood samples were drawn to measure glucose levels and to check the accuracy of the CGM device.
To compare the blood glucose level results from the blood samples with the data from the Eversense XL CGM device, accuracy assessments were measured through a technique that involves mapping paired-results on an error grid and evaluating the zones of the grid that deviate from the center. Results indicated that all pairs fell in the ‘ideal’ zones of A & B. Accuracy was also assessed through calculation of the mean (average) of the absolute relative differences between each matched-pair, known as MARD. Overall, MARD for the CGM device was 9.4 percent in the study (the lower the MARD, the greater the device’s accuracy). There were no serious adverse events related to insertion or removal procedures, or due to the device. Researchers concluded that the system is accurate and safe for adolescents through a 180-day timeframe.
“We were very pleased by the accuracy of the CGM system—it had a MARD comparable to other more- established CGM systems,” said lead study author Ronnie Aronson, MD, FRCPC, FACE, endocrinologist and chief medical officer of LMC Diabetes & Endocrinology in Canada. “We were also impressed with the stability of the life span of the sensor, which showed no significant decline in accuracy from day 60 to days 90 and 180. Additionally, given the pediatric population that we were largely studying, we were impressed by the rapidity with which CGM use became an integral part of their family life. These teens were athletic for the most part, and were particularly appreciative that both the implanted sensor and the wearable transmitter weren’t affected by their athletic gear. The adolescents’ parents expressed their own appreciation at their new ability to be more aware of their children’s glucose levels. Use of a continuous glucose sensor can have significant implications for a patient’s ability to provide optimal self-care, and awareness of their glucose trends allows patients to adjust their insulin delivery, whether by injections or pump, to better match the child’s actual needs. While we were not attempting to manage the patients’ blood glucose levels with the device in our study, the awareness of their glucose levels allowed them to spontaneously achieve a better HbA1c over time.”
Background: An implantable continuous glucose monitoring (CGM) system (Eversense® XL, Senseonics, Maryland U.S.A) recently received CE Mark for 180-day duration in adults. The current study is the first investigation of the performance of the Eversense XL through 180 days in a primarily adolescent population with type I diabetes (T1D).
Methods: This study was a prospective, single-center, single-arm, 180-day evaluation of the effectiveness and safety of the implantable CGM system among Canadian adolescent and adult participants with T1D. Effectiveness measures included mean absolute relative difference (MARD), system agreement with Yellow Springs Instrument (YSI) glucose values, and Clarke Error Grid analysis using paired CGM and reference YSI glucose analyzer values. Adult participants were inserted with two sensors and adolescent participants were inserted with one sensor in the upper arm. CGM system accuracy studies were performed every 30 days. The safety assessment included the incidence of insertion or removal procedure-related and device-related serious adverse events (SAEs) through 180 days post-insertion.
Results: Thirty-Six participants (30 adolescent/6 adult, 13 female/23 male, mean age 17±9.2 years, mean BMI 22±4 kg/m2) received the CGM system. One subject withdrew at Day 1 due to intravenous access issues. CGM system agreement with YSI glucose within 15 mg/dL or 15% of YSI glucose values (N = 7163) through 60, 120 and 180 days was 82.9% (95% CI: 78.4%-86.1%), 83.6% (95% CI: 80.4%-85.7%) and 83.4% (95% CI: 79.7%-85.5%), respectively. Overall MARD was 9.4% (95% CI: 8.6%-10.5%). Clarke Error Grid analysis showed 99% of paired values in clinically acceptable error zones A and B. No insertion/removal or device-related SAEs were reported.
Conclusions: The Eversense XL CGM system is safe and accurate through 180 days of Sensor wear in a primarily adolescent population.
Author Disclosures: R. Aronson: Other Relationship; Self; Novo Nordisk Inc., Janssen Pharmaceuticals, Inc., Sanofi, AstraZeneca. Research Support; Self; Eli Lilly and Company, Becton, Dickinson and Company, Merck & Co., Inc., Senseonics, Boehringer Ingelheim Pharmaceuticals, Inc. R. Rastogi: Employee; Self; Senseonics. C. Mdingi: Employee; Self; Senseonics. X. Chen: Employee; Self; Senseonics. K. Tweden: Employee; Self; Senseonics.