Aug. 21, 2003 — An experimental new drug may save the eyesight of older adults who suffer from a vision-robbing disease known as wet macular degeneration, according to new research.

Macular degeneration is the leading cause of legal blindness and vision impairment among adults over 60 and is also known as age-related macular degeneration (AMD) because it primarily affects older adults.

Although the “wet” form of the disease only accounts for about 10%-15% of all macular degeneration cases, it is responsible for 90% of blindness caused by the condition. The wet form is more severe and more rapidly progressing.

About 250,000 new cases of wet macular degeneration are diagnosed each year. Although the cause is unknown, the condition results in an abnormal growth of leaky blood vessels underneath the macula, which is at the center of the light-filtering layer known as the retina. The buildup of fluid in the eye causes vision to become distorted or impaired and can lead to permanent loss of vision or blindness.

Symptoms include blurred or fuzzy vision, straight lines appearing wavy, blind spots, difficulty seeing distant objects, and a decreased ability to distinguish colors.

In a study presented this week at the American Society of Retina Specialists Annual Meeting, researchers say an investigational new drug called Retaane prevented vision loss and further disease progression after two years of treatment in a group of patients with wet macular degeneration.

Experimental Drug Shows Promise

Researchers say the drug, which is not yet approved by the FDA, works by slowing or stopping the growth of new blood vessels to reduce leakage and prevent damage to the retina.

In the study, 73% of the patients treated with Retaane had stable or improved vision after two years of treatment compared with 47% who experienced similar results on the placebo.

The men and women averaged 77 years of age, and 55 of the original 128 patients with wet macular degeneration completed the two-year clinical trial of the drug.

During the study, patients were randomly assigned to receive one of three dosages of Retaane or a placebo once every six months. The drug was given to patients during a procedure at the doctor’s office in which a specially designed tool is used to deliver the drug directly behind the macula in the eye.

More Study Planned

Researcher Henry L. Hudson, MD, an ophthalmologist at the Retina Centers, P.C. in Tucson, Ariz., says these findings confirm earlier results from a one-year study and show Retaane provides long-term benefits to people with wet macular degeneration.

The drug’s manufacturer, Alcon, says it is launching a phase III clinical trial to compare the effectiveness of Retaane vs. photodynamic therapy using Visudyne, which is the current standard of treatment for wet macular degeneration, at more than 50 sites in the U.S., Canada, Europe, and Australia.

Once those results are in, the company can then apply for approval for use in treating wet macular degeneration from the FDA.