New Drug Holds Promise for People with Diabetes

Complications from diabetes might be avoided in the future with a new drug under development to slow the nerve damage that can lead to blindness or amputations. Tests of the drug have begun in people, though it could be years before the medication might gain approval for widespread use. But research presented last week in Orlando showed encouraging results in early studies.

The drug is meant to slow complications such as damage to kidneys, eyesight, nerves and circulation.

"This will not prevent everything, but we believe the vast majority of diabetic complications could be addressed," said Michael C. Van Zandt, director of chemistry at The Institute for Diabetes Discovery in Branford, Conn., which is developing the drug.

With 16 million Americans suffering from diabetes, researchers long have been looking for ways to prevent the grave consequences of the illness.

People with diabetes have trouble with insulin, the hormone that regulates sugar. Those with the most common form of the disease — type 2 diabetes — make insulin, but their bodies do not use it effectively. People with the less-common type 1 diabetes stop making insulin altogether.

Diabetics struggle to keep their sugar levels in check or risk serious problems. About 24,000 people a year go blind because of diabetes and another 56,200 lose a foot or leg to diabetic amputation, according to the American Diabetes Association.

Loss of nerve function is a frequent complication, and it often is followed by circulatory problems that lead to debilitating side effects such as amputations.

"When the nerves don’t function well, the blood vessels around them don’t work well, either," Van Zandt said.

His company’s experimental drug, called Lidorestat, works by interfering with an enzyme called aldose reductase, which pushes the body to turn glucose into another form of sugar called sorbitol.

Everyone has aldose reductase, but healthy people do not make much use of the enzyme. In contrast, aldose reductase kicks into high gear in people with diabetes, and they churn out large amounts of sorbitol.

This form of sugar can cause problems in some parts of the body. In the eyes, high sorbitol levels can cause cells to swell and die, which leads to vision problems.

In animal studies of his company’s drug, Lidorestat was found to interfere with aldose reductase and shut down production of sorbitol, Van Zandt said. The animals suffered less nerve damage as a result.

Now that human testing has begun, about 225 people at 18 different sites in North America are to take the drug for six months. The medication is not meant to replace other medications taken to control glucose levels.

"People have been working on this area for 30 years," Van Zandt said. "It’s just a very slow, evolving process."