New Treatment for Age-Related Macular Degeneration, Most Common Cause of Blindness
Treatment of age-related macular degeneration (AMD)
A new treatment improves vision in patients suffering from macular degeneration
A new treatment is available for age-related macular degeneration (AMD), the leading cause of blindness in America. AMD is a hereditary disease common among Caucasians over the age of 65. Until recently, treatments for AMD could only stabilize and slow the deterioration of vision. Now, a new treatment is available for AMD: a treatment that can result in actual improvement in vision.
The new treatment, known as "Avastin intravitreal," involves the injection of anti-VEGF antibody into the eye. VEGF is a molecule that causes blood vessels to develop under the center of the retina. When those blood vessels leak fluid and blood, severe visual loss can result rapidly. This condition is called "wet AMD" and is considered the most severe form of macular degeneration. Avastin intravitreal blocks the functioning of the VEGF molecule and thus inhibits the development of blood vessels under the retina. Improved vision can result.
Avastin was approved by the FDA nearly two years ago for the treatment of colon cancer. However, many retinal physicians now use Avastin intravitreal to treat wet AMD.
"We have used Avastin on more than 200 patients with severe macular degeneration and have seen generally good results," says Raj K. Maturi, MD, a physician of Midwest Eye Institute and a clinical assistant professor of ophthalmology at Indiana University School of Medicine. "These patients have not responded to other common methods of treatment for AMD."
The new treatment is not appropriate for all patients with wet AMD. For example, the treatment is not beneficial when the disease has produced a scar under the retina.
Until recently, the primary method of treatment for AMD was Visudyne with photodynamic therapy (cold laser treatment). Then, earlier this year, the FDA approved the use of the Macugen injections every six weeks for the treatment of AMD. Recently, Eyetech, the manufacturer of Macugen, announced the two-year results with Macugen treatment. The results showed that patients treated with Macugen, as well as untreated placebo patients, lost vision. Macugen-treated patients lost approximately two lines of vision, while the untreated patients lost approximately three lines of vision.
Several months ago, a newer study was presented regarding Lucentis, an antibody fragment that prevents new blood vessel growth under the retina by inhibiting all forms of VEGF. By contrast, Macugen inhibits only one form of VEGF. On average, patients treated with Lucentis for one year had a measurable improvement in vision and minimal side effects in the eye. Lucentis is undergoing FDA trials and will likely be approved in late 2006 or early 2007.
Genentech, the manufacturer of Lucentis, also makes Avastin. While Avastin and Lucentis have identical effects upon VEGF, Lucentis is a smaller fragment of the Avastin molecule.
As of yet, Avastin intravitreal is not reimbursed by Medicare for the treatment of wet AMD.