Jun 12 2006
Trials of an experimental drug which helps slow down the loss of vision caused by diabetes have had very optimistic results.
Diabetic retinopathy is recognized as the leading cause of blindness in the working aged population and results in enormous human and financial costs; at present laser treatments are used to treat the disease.
It is a relatively common complication associated with diabetes and can lead to a sudden and debilitating impact on vision.
In the United States, an estimated 4.1 million adults aged 40 and older have diabetic retinopathy and in 899,000 their vision is threatened.
Even mild vision loss can lead to difficulties in reading, driving, employment, and mobility as well as an increased risk of accidental injuries.
According to Lloyd Paul Aiello, MD, PhD, lead investigator of the study, the new drug ruboxistaurin, promises to be the first oral therapy to specifically reduce the risk of vision loss caused by diabetic retinopathy.
Dr. Aiello who is the director of the Beetham Eye Institute, Joslin Diabetes Center, and associate professor of ophthalmology, at Harvard Medical School in Boston, says the results are an important clinical development for the millions of people around the world who are at risk of losing their sight because of diabetes.
In early stages of the condition blood vessels in the retina leak and affect vision; in the more severe stages a multitude of fragile new blood vessels form in the back of the eye and again leak, further damaging vision.
Aiello says in late stage trials the drug reduced the risk of moderate vision loss by 41 percent, compared with a placebo, and offers a completely new approach to slowing down loss of vision.
The two studies were conducted over a three year period and involved 813 patients who received either 32 milligrams of ruboxistaurin or a placebo.
The researchers found that though the drug helped reduce vision loss in patients with the early stage it did not prevent progression of the disease to the more serious stage.
The drug which will be marketed under the name Arxxant is produced by drug company Eli Lilly.
The Food and Drug Administration in the U.S. has apparently agreed to review the data when considering approval for the drug.
The findings were presented at the American Diabetes Association's (ADA) 66th Annual Scientific Sessions in Washington, DC.