Editor's Note: The FDA approved the inhaled insulin drug Exubera in 2006, but in October 2007 the drug company Pfizer said it was halting sales of the drug because of financial reasons.
June 7, 2004 (Orlando, Fla.) -- For people with diabetes who require multiple daily insulin injections, a host of technologies on the horizon holds promise for a future that's a lot less painful. Some of these technologies were on display at the annual meeting of the American Diabetes Association.
"When I talk with patients about living with diabetes, they usually tell me that having to inject insulin several times daily isn't that big a deal. What they really object to is the fingerstick -- four, five, six times a day," Nathaniel Clark, MD, American Diabetes Association vice-president for clinical affairs, tells WebMD.
Breathalyzer for Diabetes
One group of engineers from Irvine, Calif., is developing a breathalyzer-like device that they claim can accurately detect minute quantities of so-called volatile organic compounds (VOCS, or gases) in human breath -- and we're not talking about what you smell like after eating a garlic pickle. They developed their device based on the idea that the way we burn glucose to provide cells with energy may leave behind telltale chemical signatures that can be detected by sensitive monitoring equipment.
To test the idea, they had 10 volunteers take an oral glucose tolerance test (OGTT), in which patients drink a sugar-charged drink as a test for how their bodies respond to glucose; it's widely used to test for signs of diabetes. Afterward, the researchers compared their blood glucose levels with exhaled ethanol and acetone in their breath, two gases that are released during glucose metabolism. They determined that there were small but predictable and measurable changes that could be used as the basis for a noninvasive glucose meter. Now the problem is getting the equipment, technically called a gas chromatograph, down to a portable size.
A group of Australian researchers have come up with a different approach: They developed a device that can be worn on the chest and continuously monitors skin-surface measurements to detect if the person's blood sugar levels become dangerously low, a condition called hypoglycemia (the device is named the HypoMon). The sensing unit sends the information to a small computer worn on the belt; the computer is programmed to adjust to the wearer's needs over time.
The researchers tested the device in six volunteers without diabetes and six with type 1 diabetes. They found that it was effective at detecting early signs of low blood sugar better than 80% of the time. They are currently testing whether the device could be used to monitor patients for low blood sugar while they sleep.
New Insulins a Breath of Fresh Air
Other researchers are working on forms of insulin that don't require needles.
One such product that's generating a lot of buzz is an inhaled insulin called Exubera. In two presentations at the ADA meeting, researchers looked at long-term results of clinical trials in which patients with type 2 diabetes either used the inhaled insulin in place of one or more of their daily insulin injections or in addition to oral medications.
In one study, patients who had used the inhaled insulin in clinical trials were given the chance to continue using it for up to four years. At the end of that time, their blood sugars were slightly better controlled then at the start of the study, although the levels were still higher than recommended levels. The researchers concluded that the inhaled insulin was effective at maintaining blood sugar control without apparent damage to the lungs or the respiratory system.
In a second study, researchers looked at 423 people with type 2 diabetes. The participants all had diabetes that was poorly controlled with a class of common diabetes drugs called sulfonylureas, such as Amaryl, Glucotrol, and Diabeta. The patients were assigned to receive either inhaled insulin or the oral drug Glucophage, which helps the body make better use of insulin and glucose. They found that more patients in the inhaled insulin group were satisfied with their treatment than were those who took Glucophage. In addition, the inhaled insulin was better at controlling blood sugar than Glucophage.
A different group of researchers presented information about a form of inhaled insulin called Technosphere Insulin, which is designed to more closely mimic the way the body releases insulin immediately after a meal. If this form of insulin is found to be effective, it could reduce the strain on insulin-releasing cells in the body and help to improve their function.
Not Ready for Prime Time
None of the technologies described here have been approved in the U.S. as of this writing, but many are in late-stage development.
The ADA's Clark tells WebMD that the development of noninvasive blood glucose meters "has been a far more complicated problem than anybody could have ever imagined at the outset." He also notes that even if they are approved by the FDA as expected, inhaled insulins won't totally replace injectable insulins for the foreseeable future because patients still need long-term control at night that current inhaled forms of insulin can't provide.