Diabetes and its associated complications are among the most prevalent, costly diseases in the world. Its incidence is increasing at a significant rate. Diabetes affects men and women equally but occurs most frequently in the elderly. Direct costs are estimated at about $50 billion, almost 6% of the total personal healthcare expenditures in the US.
A ten year study, the Diabetes Control and Complications Trial (DCCT) sponsored by the National Institutes of Diabetes and Digestive and Kidney Diseases, showed that "tight diabetes control," keeping blood sugar levels close to normal by recent blood sugar testing, several daily insulin shots, and lifestyle changes, was associated with a major reduction in diabetic complications. These findings led the American Diabetes Association to recommend tight control as an important way to delay the onset and dramatically slow the progression of complications from diabetes.
People with diabetes measure their blood glucose levels by sticking a
finger with a needle to obtain a blood drop that is placed on a test strip and analyzed by
a portable instrument. Repeating this procedure several times a day becomes painful,
leading many patients, especially the elderly, to perform the procedure infrequently.
Furthermore, the accuracy of some blood glucose analyzers is poor.
SYBD has developed an implantable glucose biosensor to monitor blood glucose without the need for finger sticks. Termed a biosensor because it utilizes an enzyme specific for glucose, it provides glucose measurement significantly more accurate than possible from current portable measuring devices. Once implanted in subcutaneous tissue during a simple outpatient procedure, the biosensor, which is about the size of a cardiac pacemaker, provides continuous, accurate monitoring of blood glucose which is displayed as a digital readout in a wearable beeper-sized device. Ultimately, the biosensor will be linked to an implanted insulin pump, creating a closed-loop mechanical pancreas. It is anticipated the implant life of the biosensor will exceed one year.
More than 16 million people, approximately half undiagnosed, are estimated to suffer from diabetes in the US. Between 600,000 and 700,000 new cases are diagnosed each year. About 800,000 diabetics are insulin-dependent. Mortality from diabetes and its associated complications is high; it is the seventh leading cause of death in the US. SYBD estimates the global market for the implanted glucose sensor to exceed $1 billion.
Oxygen, glucose, and enzyme electrodes, developed and patented by Dr. Clark, are used worldwide. The original implantable glucose biosensor technology had been developed and patented by Dr. Clark. New patent applications covering the sensor include a titanium encased battery and microprocessor, a silicone-sheathed platinum electrode, and a glucose oxidase enzyme system enclosed in a semipermeable cellophane acetate membrane. All components in contact with body tissue are widely used in in vivo or implantable medical devices, and the overall design is similar to implantable pacemakers. The biosensor will be implanted subcutaneously, thus measuring tissue glucose. There is evidence from animal studies that tissue glucose correlates with blood glucose in a predictable manner, and potential implant problems are avoided by not having the sensor tip in long term contact with blood. SBI projects an implant life by this method of up to 2 years. The implanted biosensor will communicate with an external, wearable receiver that will display/record calculated blood glucose levels on demand or according to a programmed schedule. A second generation, closed-loop device will include an implantable or wearable glucose infusion pumps for continuous, automated control of blood glucose levels. The technology for such infusion pumps already exists.