Macular Degeneration Treatment
In eyes with wet AMD, a chemical called Vascular Endothelial Growth Factor (VEGF) causes abnormal blood vessels to grow under the retina. These blood vessels leak and bleed, causing damage to central vision. Thanks to research efforts at Bascom Palmer Eye Institute, we now have two anti-VEGF drugs that are available for direct injection into the eye. With these medicines, it is possible to improve vision and convert wet AMD back into the dry form.
Bevacizumab (Avastin). Bascom Palmer Eye Institute’s retina specialist Philip Rosenfeld, M.D., Ph.D. pioneered the off-label use of Avastin to treat the wet form of AMD. Now used by retina specialists throughout the world for its effectiveness and low cost compared with other treatments, Avastin was the first effective treatment in clinical practice that had the potential not only to stop further deterioration in vision from wet AMD, but bring about significant improvement in vision for these patients.
Ranibizumab (Lucentis). Bascom Palmer Eye Institute’s retina specialist Philip Rosenfeld, M.D., Ph.D. pioneered the use of Lucentis as well. In June 2006, the FDA approved Lucentis for the treatment of the wet form of AMD. Lucentis and Avastin are both manufactured by Genentech, Inc. and both drugs are derived from the same monoclonal antibody against VEGF and virtually perform the same function. Lucentis was engineered specifically for the eye and tested in rigorous Phase III trials. Like Avastin, Lucentis can improve visual acuity with over 35% of patients experiencing significant improvement. Bascom Palmer Eye Institute was involved in every clinical phase of Lucentis development. Dr. Rosenfeld was principal investigator and first author on publications from the Phase I, Phase II, and Phase III trials that resulted in FDA approval for Lucentis. Lucentis is now commercially available for the treatment of wet AMD, but a single dose of the drug costs more than $2000 compared with about $50 for Avastin. Medicare covers the cost of both treatments.
Few people with macular degeneration progress to legal blindness. In these patients, low vision training is an important component of therapy. Through helpful tools and education, low vision services help patients continue activities of daily living and lead independent lives. To help facilitate this training, Bascom Palmer Eye Institute has a Low Vision Center to assess patients’ remaining vision and prescribe appropriate low vision aids.
The National Eye Institute, a branch of the National Institutes of Health, sponsored a major clinical trial called the Age-Related Eye Disease Study (AREDS). The results were published in the October 2001 issue of Archives of Ophthalmology. Scientists found that high levels of antioxidants and zinc may reduce the risk of losing vision in patients with obvious AMD. Patients with a very early stage of AMD showed no benefit from the AREDS supplement, and this supplement was never tested in people without clear evidence of AMD.
Even though the AREDS trial showed that vitamin supplementation slowed the progression of AMD, questions were raised about whether the best dosing regimen was used in the study and if other anti-oxidants could improve the outcomes. For these reasons, a new trial known as AREDS2 is underway. AREDS2 will test different doses of the supplements as well as lutein, zeaxanthin, and omega-3-fatty acids.