Dr. Alexander Eaton today presented the results of a two-year clinical study of the drug Fenretinide for the treatment of geographic atrophy, an advanced form of dry macular degeneration at the American Society of Retina Specialists conference in Vancouver. The meeting was attended by retina physicians from around the world.
The two-year research was done at 30 centers throughout the United States and included 246 study patients. The results provide hope for patients who are diagnosed with dry macular degeneration.
“This research was broad, involved a large number of institutions, and has significant implications for our patients,” said Eaton. “For the first time, the study results demonstrate that the progression of this type of macular degeneration can be significantly slowed with medication. By reducing the amount of vitamin A delivered to the retina, the drug also reduces the amount of toxic byproducts that are produced by the Vitamin A cycle. Since vitamin A and the vitamin A cycle are critical to healthy vision, this is especially important as these byproducts are continually being produced.”
One Southwest Florida participant, Herbert Ruescher, has reported decreased vision since completing the study in February and discontinuing use of the study medication he received. While we can not be sure he received the active drug, his experience suggests he did. With Fenretinide the desired effect of the drug is to prevent vision loss.
Ruescher, who had been treated for dry macular degeneration in the past, participated in the study for two years. During the study, he says his vision didn’t get worse at all, describing his vision loss while taking Fenretinide as “nil.” Since stopping the medication at the study’s conclusion, the patient experienced rapid deterioration and describes his vision as “blurry” and “hazy” as if he has tears in his eyes. Also, during the study, Ruescher says his eye exams were “status quo,” but at his latest exam the doctor could see a change for the worse. He believes Fenretinide stopped his vision from getting worse while he took it.
“Eyesight is a very precious thing,” says Ruescher. “I had to stop driving for safety reasons so I’m interested in anything that will help. They are doing a good job. Dr. Eaton and Dr. Wafapoor are very fine doctors.”
The incidence of this form of dry macular degeneration has been estimated to be around 2 percent at 75 years of age and 22 percent at 90 years of age. In the study, the patients who received the higher dose of the medication showed a 50 percent reduction in the growth of lesions.
In addition, the drug was found to inhibit the development of exudative macular degeneration from 18.3 percent in the controls, to around 9 percent in the treatment group. This is approximately a 50 percent reduction, and occurred in both the lower and higher doses of the medication used in the study.
“We have not seen any other compound produce this kind of reduction in both of these vision threatening forms of macular degeneration, so it is really exciting,” said Eaton.
After detecting this finding, additional research with Fenretinide shows a direct effect of the medication on the production of vascular endothelial growth factor (VEGF), a protein that stimulates the growth of blood vessels and plays an important role in the development of wet macular degeneration.
“What makes this drug so incredible is it appears to work on two different pathways that are important in the development of macular degeneration,” said Eaton. “It slows the development of dry macular degeneration, while reducing the incidence of wet macular degeneration. As far as we are aware, this is the first compound to have such a benefit.”
The side effects of Fenretinide include difficulty with night vision and mildly elevated results for liver function screenings. The night blindness was reversed when the drug was discontinued.
Before Fenretinide can be released, a final research study will be needed. This is expected to begin soon and to take two or three years to complete.
Retina Health Center and the Macular Degeneration Research Center were established in 1993 by Dr. Alexander M. Eaton, a long-time Southwest Florida resident who has been practicing ophthalmology in Lee and Collier counties for more than 17 years. Eaton has been the principal investigator for numerous studies to prevent and treat macular degeneration. For more information on the latest studies or to make an appointment, call 239-337-3337 in Fort Myers or 239-793-5200 in Naples, or visit http://www.retinahealthcenter.com/.