The Race For The Non-Invasive Sensor
I'm sure you've heard about the non-invasive blood glucose sensors that everyone in the diabetic meter business is talking about; it is, after all, big news. The ability to take accurate glucose readings without the traditional finger-stick would be a blessing to people with diabetes. The estimated $500 million prize going to the inventor of such a device would be a blessing to whichever company produces the first one. The obstacles involved, however, insure that whoever wins it will have to work long and hard.
Most of the companies working on a non-invasive system (one that doesn't cut or puncture the skin) have placed their hopes on near infrared spectroscopy (near IR)- the so-called "Dream Beam." Spectroscopy is a method of analyzing chemical compounds mainly by shining light through them. The problem lies in separating the relatively tiny glucose readings from the much stronger and more abundant readings produced simultaneously by the other compounds in both blood and flesh. Other methods are also being researched, but the companies involved are being very closed-lipped. When this reporter contacted John Smith of LifeScan, the largest manufacturer of home monitors, he said: "When we have something concrete everyone will know-until then, no one will."
According to their press releases, Futrex has already run clinical trials on a near IR meter and is working out the bugs, while Biocontrol will soon be conducting trials on their non-invasive system at two hospitals in Illinois and has apparently leased a manufacturing facility for the production of their sensor. Sandia, which has been conducting trials for the last two years, claims to have developed a calibration table and determined glucose levels from test subjects that accurately matched their near IR sensor readings to results from blood tests. They warn, though, that there are tests yet to be run and the cost involved may keep their technology off the market for years to come. Solid State Farms won't say anything until it has something finished, but implied that it was close and was using something other than near IR.
The company whose claims seem to be the most hopeful, however, is called Biotronics Technologies Inc. (see Navy article, page 9). According to Dr. Ken Shlager, the head of the research team, they have been working on a non-invasive "blood spectrometer" for the Navy which analyzes nine substances in the blood, including glucose. Clinical trials involving 500 patients were run at the Bethesda Naval Hospital in Maryland and the Froedtert Hospital in Milwaukee. According to Dr. Schlager, results from the Biotronics monitor correlated accurately with actual substance levels in the blood. The prototype (two boxes attached to a personal computer) has been sent to San Diego for testing by the Navy; if approved, a monitor could be ready for sale to hospitals by late 1994.
The reality of the situation may not be as bright as the press releases make out, however. Dr. Yitzhak Mendelson of Worcester Polytechnic Institute, one of the leading researchers of the Pulse Oximeter, pointed out that those who claim a near infrared system is just around the corner haven't made all of their data public, so there is no way to determine the validity of their research. "All these claims of 'soon' are coming from industry, not academic researchers," he said in a phone interview, and went on to caution that similar claims had been made about other technology in the past that ended up taking 10 or 15 years before a product was successfully delivered.
Neither is Dr. Mendelson in the minority for his skepticism; most of the researchers interviewed said that near IR, though possible, was years away from being marketable. The problems of accuracy and cost have led one researcher to believe that a near IR sensor may not be available until the next century, and almost everyone agrees it will be seen in hospitals long before a home unit becomes available.
Despite the rhetoric the race goes on. The market, after all, will be there until a cheap, painless alternative to the finger-stick is available. However, it may be premature to say that the race is almost run, and those who have been expecting a non-invasive sensor any day now should probably be prepared for a long wait.Click Here To View Or Post Comments