Evaluation of the efficacy and safety of a new Continuous Glucose Monitoring System in adult patients with type 1 and type 2 diabetes

This is a prospective, single arm, open-label, interventional, confirmatory study to evaluate the efficacy and safety of a novel continuous glucose monitoring (CGM) system by evaluating the glucose measured in comparison with the reference standard, which is venous blood glucose, and to demonstrate the safety of the novel CGM system (from here onwards referred to as nCGM) by observing adverse events occurring during the attachment of the device in adult patients with type 1 and type 2 diabetes. The study will enrol 50 adults (18 years and over). The nCGM system consists of (1) an interstitial glucose sensor worn in the upper arm that continuously measures the glucose concentration in the interstitial fluid, (2) a transmitter that transfers the results wirelessly and (3) a handheld receiver (mobile phone) that receives and displays the sensor glucose data, including the current glucose level, glucose history and a predicted glucose trend. The nCGM can be worn for up to 15 days. Participants will not use the investigational device to make clinical or treatment decisions. Subjects will be involved in the study for 16 days and will visit the study site 5 times during the study. Subjects will wear nCGM for 15 days to monitor their glucose values while maintaining their usual treatment method. All subjects will wear 2 nCGM devices, one on each upper arm. Subjects will calibrate the nCGM devices once every 12 hours during the first 24 hours of the study, and thereafter once every 24 hours using a self-monitoring of blood glucose device (blood glucometer, hereafter referred to as SMBG). During the study period, subjects will draw capillary blood at least 8 times a day using SMBG and record the results. On day 1 of the study, subjects will receive training on the use of the nCGM system and SMBG device for measuring of capillary blood glucose, and will be instructed to keep a daily blood glucose log. The training on the use of the study devices will be done by trained members of the study team and take approximately 30 minutes. Subjects will be assigned to an ‘early group’ or ‘late group’ based on their personal preferences. Those in the early group will visit the study site on days 1, 5, 10, 15 and 16, and those in the late group will visit the clinic on days 1, 2, 5, 10 and 16. On site on days 1/2, 5, 10 and 15/16, subjects will undergo safety assessments and have venous blood sampling every 15 min for approximately 8 hours using an intravenous catheter, and capillary blood sampling using SMBG will be done in parallel. During 4 of these in-clinic days, glucose excursions will be induced by consumption of a high-glycaemic index (HGI) meal, and delayed and increased insulin boluses. The HGI meal will account for approx. 20% of daily caloric needs with a composition of around 65% carbohydrates, 15% protein, 20% fat. The HGI meal will have low fibre content and be adapted to local customs and dietary requirements, and include one serving of fruit juice. Subjects will be closely monitored by trained study staff experienced in medical care during these glucose excursions, in order to ensure subject safety. At home, subjects will be instructed to test their blood glucose at least 8 times daily and record all values. After the in-clinic procedures on day 5, subjects will continue to perform blood glucose testing every 2-3 hours, including overnight, until the morning of day 6. The study ends after completing the in-clinic blood sampling on day 16, when subjects remove the nCGM devices, complete a device satisfaction questionnaire, and undergo a final safety assessment. Subjects will receive a follow-up phone call by a member of the study team 14 days after study completion.