In a pilot study conducted previously by our group using the prototype 1st generation LabPatch system (PRECISION study, 2016-31), we found that LabPatch glucose measurements strongly correlated with those of YSI, OneTouch Verio, and Freestyle lite in a sample of 30 subjects (Tomah et al Diabetes Jun 2020, 69 (Supplement 1) 885-P). However, we observed significant inter- and intra-subject variability of LabPatch glucose measurements. Factors that may have contributed to this variability include: manual manufacturing of the 1st Gen LabPatch circuit chips and/or variability in the pressure applied by subjects on the circuit chip at each measurement. To control for these variables with the goal of improving overall accuracy, Cambridge Medical Technologies, LLC significantly improved and completely automated the manufacturing process of the circuit chips. In addition, the system has been miniaturized to a more user-friendly layout and with a clasp unit to control for pressure applied by the subject finger on the circuit chip.~The 2nd Gen LabPatch system consists of:~I. The 2nd Gen LabPatch chip which lies in the center of a clasp unit. The chip measures approximately 15.7 mm [0.618] x 15.7 mm [0.618]. The chip has a telescopic micropipette which draws interstitial fluid to be analyzed for glucose levels. The chip is also able to measure skin temperature to ensure appropriate skin contact II. A LabPatch clasp device III. A wire that connects the clasp unit to a Windows tablet which will communicate with the clasp via an application. Each data point will be viewed on the tablet and the application will also have some limited graphing capabilities to view trends of previous measurements The system has been previously tested on 10 human subjects with type 1 diabetes, each for six hours, at the Georgetown University Medical Center under clinical conditions supervised by a medical team including an endocrinologist and dermatologist. The test confirmed the absence of pain or abnormal physical sensation and that the operation of the device causes no tissue damage,instigates no neural sensation for the subject, and leaves no blemish on the skin. No skin damage incurred by the LabPatch operation was detected.~The 2nd Gen LabPatch system is an in vitro diagnostic device (IVD), does not have significant risk and is therefore exempted from the IDE requirements. In addition, the device uses an in vitro diagnostic technology that does not create adverse events and therefore a data safety monitoring board (DSMB) is not requited.
The purpose of this study is to evaluate the accuracy of the Cambridge Medical Technologies, LLC second generation (2nd Gen) LabPatch glucose sensing system compared to a laboratory glucose analyzer (YSI 2300 STAT Plus) and 2 commercial glucometers, OneTouch Verio and Freestyle Lite. The primary endpoint of this study is the mean absolute relative difference (MARD) for 2nd Gen LabPatch system compared to each of the above mentioned glucose references over a 6 hour outpatient visit.