Medtronic Diabetes (Northridge, California) is one step closer to ultimately having an artificial pancreas for diabetic patients with the PMA supplement approval of its Guardian RT continuous glucose monitoring system, which measures glucose levels in the interstitial fluid, where cells get oxygen and nutrients, including glucose.
The system, which will be available to consumers from their physicians with a prescription, continuously measures glucose levels around the clock, even during sleep. If glucose levels get too high or too low, the device sounds an alarm or vibrates.
Deanne McLaughlin, communications manager for Medtronic Diabetes, told Diagnostics & Imaging Week that this is really the first “viable device” for continuous glucose monitoring entering the market for consumers.
The previous iteration of the device allowed continuous glucose monitoring, but patients had to visit their doctors, who would download the information, she said. The Guardian RT is meant specifically for consumers.
“It’s designed to display real-time glucose values every five minutes, and so what you really get is – we can guess about 288 fingersticks a day with this technology, as opposed to the two to three fingersticks that [diabetics] would normally take,” she said.
The device will be launched in certain U.S. cities, which will be announced in September, she said. Based on the sPMA secured from the FDA last month, the device can be used by those age 18 or older with either Type 1 or Type 2 diabetes.
The Guardian RT System uses a glucose sensor, a transmitter and a monitor. Included with the system is a docking station and therapy management software, the company said, which allows patients and healthcare professionals to download information to a computer to view trend reports and charts.
The sensor is very tiny and is slipped under the skin by the patient or the physician. It can be worn for three days, when it must be replaced. It is worn on the abdomen, and the patient typically changes the location where the sensor is inserted. It is inserted using the Senserter, an automatic insertion device, the company said. Medtronic’s CGMS System Gold and the Paradigm Real-Time System, an insulin pump system, product lines use the same subcutaneous sensor.
The sensor measures glucose levels in the interstitial fluid following a two-hour initialization period. Medtronic Diabetes said the “sensor converts glucose values from interstitial fluid into an electronic signal, which represents the amount of glucose in the blood.
Before any therapy can be administered, the patient must first do a traditional fingerstick test, however.
According to Medtronic Diabetes, the transmitter connects to the glucose sensor and attaches to the skin by an adhesive patch. Using radio frequency, the transmitter sends glucose values from the sensor to the monitor every five minutes. The transmitter has a battery lifespan of about one year, even with “near continuous” use, the company said.
Medtronic Diabetes said that the monitor, which fits on a belt like a pager, “should not be exposed to water; however, patients can easily shower or bathe without interrupting their glucose data since the monitor will receive a signal as long as it is within six feet of the transmitter.”
Patients can download device data and personal information to their computers by using a docking station on the monitor called the “Com-Station.”
Asked if the technology might be overwhelming to the less technology-savvy, McLaughlin said, “No. Diabetes patients are very used to, especially Type 1 [diabetics], at managing data. It’s a data-driven disease, and they have a lot of handbooks they use. And the technology actually helps them store their information, so it’s actually easier. You download it into a report, and it’s all combined. So, it’s actually easier.”
Results of a pilot study reported during this year’s American Diabetes Association (Alexandria, Virginia) annual meeting in San Diego in June indicated that 94% (15 of 16) of patients participating in the small study at the Charite Clinic (Berlin) used the real-time glucose values and/or high and low glucose alerts that came via the Guardian RT system to control glucose fluctuations.
Other findings during the 10-day study included 81% of the participants reporting greater satisfaction with their blood glucose control; 75% adjusting their insulin delivery based on Guardian RT data; 63% changing their diet as a result of that data; and 31% making “lifestyle changes” based on the insights they received from real-time continuous monitoring.
In a research report, First Albany Capital (San Franisco) issued a “strong buy” for Medtronic. In the report, analysts said that the “bottom line” is, “We think FDA approval of Guardian RT moves Medtronic one important step forward toward its goal of creating the first artificial pancreas.”
McLaughlin said that the approval of the Guardian RT Continuous glucose monitoring system is headed toward the first artificial pancreas. “Well, it’s very true. It just bodes well, because the next step is really to take this continuous glucose monitoring technology and integrate it with an insulin pump. And by doing so you have a system that continuously monitors glucose and delivers insulin, and that’s called a sensor augmented pump system.
She added, “We expect that to be very revolutionary, and that would be kind of the baseline system ... the first major step in order to really advance into an artificial pancreas and move the technology forward.”
Several other companies are working on continuous glucose monitoring devices. Among them are DexCom (San Diego), which is seeking FDA approval of its Short-Term Continuous Glucose Monitoring System; Abbott Diabetes Care (Alameda, California), with its FreeStyle Navigator Continuous Blood Glucose Monitor; and Smiths Medical MD (St. Paul, Minnesota), whose CoZmonitor Blood Glucose Module was developed in conjunction with Abbott Diabetes Care.
Insulin pump maker Animas (West Chester, Pennsylvania) earlier this year acquired the intellectual property rights to the Cygnus (Redwood City, California) GlucoWatch and GlucoWatch Biographer devices, and SpectRx (Norcross, Georgia) is developing a patch with a sensor to test interstitial fluid.