Changes coming in AMD treatment strategy, surgeon predicts

DANA POINT, Calif. — Use of photodynamic therapy in the treatment of wet age-related macular degeneration is growing, but molecular drug therapies will outpace it in coming years, predicted Carmen A. Puliafito, MD, MBA, at a meeting here.

Macular degeneration is one of the most problematic diseases for retinal specialists, Dr. Puliafito said at the Ocular Drug and Surgical Therapy Update meeting. Although there have been recent improvements in treatment options with the development of photodynamic therapy (PDT), there are also more cases of AMD now because of the aging of the population, he said.

PDT is now used to treat classic and occult AMD, as well as other conditions such as pathologic myopia, Dr. Puliafito said. Although it is an effective treatment, it is not without complications, he noted.

Dr. Puliafito said PDT closes blood vessels but can also upregulate vascular endothelial growth factor (VEGF) and spur growth. Cystoid edema is another potential complication of PDT, he said.

Research has shown VEGF to be an important molecule that is a key promoter of neovascular growth in AMD, Dr. Puliafito said. Anti-VEGF agents were first cloned and purified in 1985, he said.

Two molecular therapies for AMD are showing positive results by blocking VEGF with different mechanisms, he said. Macugen (pegaptanib, Eyetech/Pfizer) and Lucentis (ranibizumab, Genentech) are both undergoing clinical trials and are not yet commercialized. Macugen is an aptamer that, when injected, works quickly to block VEGF, he said. Lucentis appears to “cure” choroidal neovascularization for a period of time, he said.