PRECISION Study: Evaluating the Accuracy of the LabPatch Continuous Glucose Monitor

Study design:

This is a cross-sectional, pilot, precision, single center, single-arm study, enrolling 30 adult subjects with type 1 or type 2 diabetes treated with insulin.

The study will include both a screening visit and a single study visit.The accuracy of the LabPatch CGM will be evaluated during the study visit, comparing to YSI 2300 STAT Plus, OneTouch Verio and FreeStyle Lite.

Screening Visit:

Following the informed consent process, screening evaluation will determine subject eligibility for enrollment, including:

• Demographics- including age, sex at birth, race/ethnicity, dominant hand, and BMI.
• Diabetes History - including type of diabetes, date of diagnosis or length of diabetes, history of DKA and severe hypoglycemia, current treatment [type of insulin and type of insulin delivery (injections or insulin pump)], insulin doses, and when applicable: basal rates, correction factors, glucose targets, insulin duration, insulin to carbohydrate ratios, sliding scales.
• Current and Past Medical History - including current medications.
• Physical examination and vital signs- including height, weight, blood pressure, pulse, assessment of venous access for repeated blood draws.

Study Visit (visit window: screening visit + 0 to 30 Days):

Subject Admission

The subject will arrive at the clinical research center at Joslin Diabetes Center during the day, no later than 10:00 AM and the following will be performed:

• The study team will confirm the absence of fever, nausea or vomiting that might occur within 24 hours before the visit.

During this visit the following procedures will be conducted:

• Measurement of BP and anthropometric parameters will be taken and include, weight, height and BMI.
• An intravenous line will be inserted through which all blood samples will be collected.
• The study team will prepare the sensor and its connectors appropriately.
• A fasting blood sample will be collected for measurement plasma glucose, A1C and complete blood count.
• A breakfast meal will be given followed 3-4 hours later by a lunch.
• Insulin will be injected before breakfast and lunch based on the blood glucose value before the meal using the same insulin regimen by the subject in the outpatient setting.
• At 15 minute intervals, subject will sit down at a mobile "overbed" table that has the LabPatch CGM. Then, they will press with their major finger on a circular push-button for about 15 seconds for each measurement of glucose. When pressed, the LED ring light illuminates in blue, indicating that the glucose measurement has commenced. The finger will remain in place until a beep is heard, then lifted.
• Twenty to 22 blood samples will be drawn during the study visit. The samples will be drawn at the following intervals: baseline, every 15 minutes for 2 hours after breakfast, every 30 minutes till the lunch time, and every 15 minutes for 2 hours after lunch. A total of about 110 mL of blood will be drawn during the visit.
• If all admission criteria are not met, the subject will be rescheduled. If all of the admission readiness conditions are met, the subject will be admitted to the Clinical Research Center (CRC).

Before discharge:

• Finger-stick glucose will be assessed.
• If plasma glucose is \<70 mg/dL, 15 gm of carbohydrates will be given to raise the glucose to ≥100 mg/dL and blood glucose will be checked after 15 min and another carbohydrates dose is given if blood glucose is still \<70 mg/dL. Subject will be only allowed to go home when the blood glucose is >100 mg/dL and stable.

Subject Instructions prior to the visit

• Prior to admission, subjects should check their blood glucose, if it is \<70 mg/dL or subject feels hypoglycemic symptoms, then they should eat a snack prior to coming to the visit

Estimated Visit Duration

• The total duration of the inpatient visit is approximately 6 hours with screening visit being approximately 2 hour. The study time may be extended for glucose stabilization prior to discharge.