Continuous glucose monitoring system approved in US

In a first, a patch device that continuously monitors blood glucose levels in diabetics, and can be integrated with automated drug and insulin delivering systems, has been approved in the US.

The US Food and Drug Administration (FDA) permitted marketing of the Dexcom G6 integrated continuous glucose monitoring (iCGM) system.

This is the first type of continuous glucose monitoring system permitted by the agency to be used as part of an integrated system with other compatible medical devices and electronic interfaces, which may include automated insulin dosing systems, insulin pumps, blood glucose metres or other electronic devices used for diabetes management.

The Dexcom G6 is a patch device, about the size of a quarter, that is applied to the skin of the abdomen and contains a small sensor that continuously measures the amount of glucose in body fluid.

The device transmits real-time glucose readings every five minutes to a compatible display device such as a mobile medical app on a cell phone and will trigger an alarm when a patient's blood sugar enters a danger zone soaring too high or dropping too low.

If it is integrated with an automated insulin dosing system, a rise in blood sugar would trigger the release of insulin from the pump. The patch device should be replaced every 10 days.

"The ability of this device to work with different types of compatible devices gives patients the flexibility to tailor their diabetes management tools to best meet personal preferences," said Donald St Pierre, acting director of the Office of In Vitro Diagnostics and Radiological Health in the FDA's Center for Devices and Radiological Health.

Diabetes impairs the body's ability to make or properly use the blood glucose-regulating hormone insulin.

Patients must regularly monitor their blood sugar levels since continuously high blood sugar levels can lead to heart disease, stroke, blindness, kidney failure and nerve damage leading to amputation of the toes, feet or legs.

Blood sugar levels can also fall too low, which can cause dizziness, confusion, unconsciousness and, in extreme cases, death.

An earlier generation of the technology, the Dexcom G5 system, received FDA approval in 2016 but was not designed as an integrated system to be used with compatible devices.

Unlike the earlier model, the Dexcom G6 version is factory calibrated and does not require users to calibrate the sensor with fingerstick blood glucose measurements.

In addition, it has an updated sensor probe that minimises interference with the pain reliever acetaminophen.

The FDA evaluated data from two clinical studies of the Dexcom G6, which included 324 adults and children aged 2 years and older with diabetes.

Both studies included multiple clinical visits within a 10-day period where system readings were compared to a laboratory test method that measures blood glucose values. No serious adverse events were reported during the studies.

Risks include hypoglycemia (low blood sugar) or hyperglycemia (high blood sugar) in cases where information provided by the device is inaccurate and used to make treatment decisions, or where hardware or set-up issues disable alarms and alerts.

Patients may also experience skin irritation or redness around the device's adhesive patch.