PMCF Study of GX-01S CGM in Adults With Diabetes (PROMISE-GX)

Diabetes mellitus remains one of the most prevalent chronic diseases worldwide, contributing significantly to morbidity, mortality, and healthcare costs. For individuals with Type 1 Diabetes (T1D) and many with Type 2 Diabetes (T2D), insulin therapy is essential for maintaining glycemic control and preventing acute and long-term complications. Traditional self-monitoring of blood glucose (SMBG) via fingertip testing, while effective, has limitations including pain, inconvenience, and the inability to capture glucose trends or nocturnal fluctuations.

Continuous Glucose Monitoring Systems (CGMS) have emerged as a transformative technology in diabetes management. By measuring interstitial glucose levels at frequent intervals, CGMS offers real-time glucose data, trend information, and alerts for hypo- and hyperglycemic events. These features support more informed treatment decisions, reduce the burden of fingertip testing, and have been shown to improve glycemic outcomes such as Time In Range (TIR) and Hemoglobin A1c (HbA1c).

Despite the growing adoption of CGMS, real-world evidence on patient acceptance, clinical benefits, and the impact of device-specific features-such as remote data sharing and retrospective pattern analysis-remains limited, particularly in European populations. Furthermore, understanding the reasons for device discontinuation, including skin reactions, sensor insertion burden, and body image concerns, is critical for optimizing patient-centered care.

The GX-01S Continuous Glucose Monitoring System is a single-use, real-time medical device designed to provide continuous interstitial glucose readings for the management of diabetes. The system consists of three primary components: (1) a sterile sensor with an integrated applicator, (2) a transmitter for wireless data transfer, and (3) the LinX mobile application for real-time display and alert management. The sensor is designed for a wear life of up to 15 days.

This PROspective Post-Market Clinical Follow-Up (PMCF) study aims to evaluate the clinical benefits of the GX-01S CGM System in adult patients with diabetes. The investigation will focus on improvements in glycemic control, treatment satisfaction, device usability, quality of life, and safety outcomes in a real-world European cohort. Findings from this study are intended to support the clinical utility and patient acceptance of CGMS as a standard of care in diabetes management.

The primary objective of this study is to demonstrate that use of the GX-01S CGM System can improve glycemic control, as measured by an improvement in CGM-derived glycemic metrics (TIR, Time Above Range [TAR], and Time Below Range [TBR]) after 30 days of device usage, compared to baseline. Baseline is defined as the blinded 15-day CGM run-in period during which participants use the GX-01S CGM without access to real-time glucose data.

The secondary objectives are to assess efficacy, ease of use, and safety of the GX-01S CGM System, as well as patient treatment satisfaction and quality of life. Secondary outcomes include change in HbA1c, treatment satisfaction measured by the Diabetes Treatment Satisfaction Questionnaire (DTSQ), satisfaction and quality of life measured by the CGM Satisfaction Scale (CGM-SAT), device usability measured by the Post-Study System Usability Questionnaire (PSSUQ), and the number and type of (serious) adverse events and device deficiencies.

The study is a post-market, commercial, prospective, interventional, single-arm multicenter study. A total of 100 adult patients with T1D and T2D will be enrolled, with at least 70% being T1D patients and more than 50% on a stable insulin regimen. Enrollment will take place across multiple centers in Europe. Participants will be followed for approximately 135 days (about 4.5 months), consisting of a 15-day blinded run-in period and a 120-day unblinded period with full access to real-time glucose data.

The sensor insertion is a minimally invasive procedure performed by the participant under the supervision of qualified site staff. Sensors will be applied to the back of the upper arm and replaced every 15 days. Participants will use a study-specific blinded application during the run-in period and the commercial LinX application during the unblinded period. Investigators will have remote access to sensor data through the Pancares Web Portal for monitoring and data collection.

The study has received ethical approval from the relevant Ethics Committees and will be conducted in compliance with ISO 14155, the Declaration of Helsinki, and the EU Medical Device Regulation (MDR) 2017/745. Results will be published to support the clinical utility of the GX-01S CGM System in diabetes management.