An age-related macular degeneration drug called Eylea has been shown to work in patients when two other drugs, Avastin and Lucentis, fail to stop blood vessel leakage and loss of vision.
All of the drugs in this class of medication are biological, protein-based medications, not small molecule pharmaceutical drugs. Lucentis and Avastin are antibodies that are relatively similar and block a protein called vascular endotherlial growth factor (VEGF), which causes the growth of new blood vessels. Eylea works through the same mechanism, but was independently developed by another company, Regeneron out of Tarrytown, N.Y.
During the course of treatment with Lucentis and Avastin, some patients can become resistant to these drugs and leaking of the blood vessels can begin again, leading to vision blurring and loss. This has spurned research into drugs that can be used as a second line of defense after the first set of drugs fail. In reaction to the new discovery for the drug, Dr. Mahajan said, “We have a 50-50 chance of making previous nonresponders better, and 50-50 is a whole lot better than zero.”