Users of the Dexcom G5 Mobile Continuous Glucose Monitoring System (Dexcom G5) can now rely on the device to make diabetes treatment decisions using two finger pricks daily, not multiple ones, following the U.S. Food and Drug Administration's (FDA) approval of expanded use of the device.
On Tuesday, the FDA granted the expanded indication. Users must still calibrate the device at least two times a day by testing a fingertip blood sample with a blood glucose meter. 1
Experts hailed the decision as a welcome change, with some calling it a game changer and others noting that the FDA approval is simply the official blessing on what has been a common practice.
The system has an externally worn glucose sensor. It measures blood sugar levels continuously, known as continuous glucose monitoring (CGM), and displays these values every five minutes. It works by using a small, flexible metal wire or sensor inserted just below the skin. It generates a small electrical signal in response to the amount of sugar present there. That is converted to a glucose reading.
It is approved for use in managing diabetes in those age two years and older.
The expanded approval ''removes the burden of multiple finger sticks" and "empowers people to act on the information [displayed]," says Nicholas Argento, MD, an endocrinologist in Columbia, Maryland, who has type 1 diabetes. He has served on the speakers' bureau for Dexcom. In reality, he says, many patients have been doing this for a long time, acting on the displayed information without constant finger pricking. 2
"The majority who use this are type 1," he says. "Probably 10 percent of the patients I see on continuous glucose monitoring have type 2."
The expanded approval will translate to convenience for many, such as workers for whom it's inconvenient to step away and do a finger prick, Dr. Argento says. "In the workplace, people often have no reasonable alternative but to act on this information in real time [without taking a blood sample]," Dr. Argento tells EndocrineWeb.
"This approval may be very helpful for people with diabetes who are often overwhelmed with the responsibilities associated with daily diabetes self-management," says Susan Weiner, MD, RDN, CDE, DCN, a member of EndocrineWeb's editorial board and the 2015 AADE Diabetes Educator of the Year.
Reducing the finger sticks to two a day, she says, ''reduces some of the burden of carrying a meter with you at all times to check blood sugars."
However, she offers a caveat: "Proper use of the device must be stressed, to avoid potential problems associated with hypo or hyperglycemia."
According to Gary Scheiner, MS, CDE, of Integrated Diabetes Services, Wynnewood, PA, the decision is ''the FDA's way of catching up with what has been a common practice." He, too adds a caveat, saying that "It is also very important to recognize situations in which CGM data should not be trusted." Among those situations, he says, is if you have limited experience using the system or just started. "During the first 12 to 24 hours of use, CGM tends to be considerably less accurate than it will later become," he says. "It takes a few calibrations and formation of a stable 'wound' at the sensor site for the system to hone in and become reliable.''
If the sensor number is way off from the meter, go with the meter until the two match up more closely, he says.
Another diabetes educator, Amy Hess-Fischl, MS, RD, LDN, CDE, advisory board member to EndocrineWeb and program coordinator of the Teen and Adolescent Diabetes Transition Program at the University of Chicago, had a one-word immediate reaction: "Finally!"
She says the new indication ''really can be a game changer for those who have a barrier to testing." She suspects it may improve how people manage their diabetes. "I really look forward to hearing how my patients have positively changed their diabetes care because of this,'' says Hess-Fischl.