What is Avastin (bevacizumab), and how does it work?
Avastin is a monoclonal antibody that works by attaching to and inhibiting the action of vascular endothelial growth factor (VEGF) in laboratory experiments. VEGF is a substance that binds to certain cells to stimulate new blood vessel formation. When VEGF is bound to Avastin, it cannot stimulate the formation and growth of new blood vessels (angiogenesis).
Avastin™ (bevacizumab) is an FDA approved injectable drug for the treatment of colon cancer. Avastin™ (bevacizumab) is one of a class of drugs called Anti-VEGF (Vascular Endothelial Growth Factor). This drug reduces the growth of abnormal blood vessels. Avastin™ (bevacizumab) is being used by retinal specialists (as an off-label use) in the treatment of wet macular degeneration, or AMD. AMD exists in two forms, dry Age-related Macular Degeneration and wet Age-related Macular Degeneration. Wet AMD is a serious, vision-threatening condition. In wet AMD abnormal blood vessels behind the retina start to grow in the area of the retina known as the macula. These blood vessels leak blood and fluid causing damage to the macula and loss of vision. Two published studies (see below) have shown Avastin™ (bevacizumab) to benefit macular degeneration patients whose eye were treated with Avastin™ (bevacizumab) injections. In both studies the drug was reported to be well tolerated.
Published results of initial trials of Avastin™ (bevacizumab) for the treatment of wet Age-related Macular Degeneration have reported promising results. A study conducted by Dr. Philip J Rosenfeld, MD, PhD, associate professor of ophthalmology at Bascom Palmer Eye Institute, showed the eye treated with Avastin™ (bevacizumab) improved significantly. While there are a few other treatments for wet Age-related Macular Degeneration, eyes treated with Avastin™ (bevacizumab) were reported to improve vision in as little as one week according to Dr. Rosenfeld. Ophthalmologists use a very small amount of Avastin™ (bevacizumab). Typically, they will ask a compounding pharmacy specializing in sterile (aseptic) compounding to transfer the Avastin™ (bevacizumab) from the manufacturer's vial into prefilled syringes containing a single dose. This injection is then administered by the ophthalmologist, usually in an office setting.
New Studies on "Treat & Extend for Avastin
Macular Degeneration information from the American Academy of Ophthalmology