Because there was no other treatment available at that time, in early 2004, Philip Rosenfeld, MD, PhD, and colleagues at the Bascom Palmer Eye Institute in Miami, began treating AMD patients with the anti-VEGF cancer drug Avastin. Avastin is currently approved by the USA Food and Drug Administration (FDA) as an intravenous therapy for metastatic colorectal cancer patients. Although they are not the same molecule, Avastin is thought to work by a similar principle as another anti-VEGF treatment called Lucentis, namely by blocking the production of VEGF. VEGF, which is also produced by cancer cells, prompts the abnormal growth of blood vessels, also known as angiogenesis. Anti-VEGF drugs bind together with VEGF and interfere with its ability to stimulate blood vessel growth.
The first study of Avastin for AMD treatment was conducted by Dr. Roseneld, and was called Systemic Avastin for Neovascular AMD (SANA). In this and subsequent clinical case studies, which consisted of intravitreal injections of Avastin, individuals who were clinically followed reported improvements in visual acuity comparable to Lucentis with no serious adverse events. It is important to note that these clinical studies were not conducted as randomized clinical trials. Based on these results, the use of Avastin for the treatment of AMD appears to have been broadly accepted by retinal specialists around the world.
The use of Avastin in the eyes, an indication for which it is not approved, is called off-label use. The off-label use of drugs is legal in North America, Europe, and Asia, and is a practice that is accepted by physicians, healthcare providers and institutions, and some insurers. There is growing anecdotal evidence about the efficacy of the off-label use of Avastin. However, at this time, published reports on Avastin are limited to a number of human clinical case series in and a few animal studies on intravitreal injection.
There have been no randomized controlled clinical trials, nor are there any broad, scientifically-accepted published reports in this regard. In fact, due to the fact that Avastin is a full-length antibody, some researchers assert that it will not be as effective in the long term because it cannot penetrate all layers of the eye as well as the fragment antibody Lucentis.
Scientifically proven answers to questions about Avastin will only be known following the completion of clinical trials and publication of the results. Clinical trials comparing Avastin and Lucentis are currently ongoing in the United States and England. The American CATT (Comparison of Age-Related Macular Degeneration Treatments Trials: Lucentis-Avastin Trial) is currently enrolling clinical trial participants in 56 locations across the USA. This study started enrolling participants in February 2008, with preliminary results expected in February 2011. A study, called the IVAN trial is also ongoing in England.
While we await the clinical trial results, our position is that individuals must make an informed decision about treatment in consultation with their own retinal specialist. According to the American Medical Association, informed consent refers to significantly more than the process of signing a ‘consent to treat’ form. Rather, informed consent refers to the communication that takes place between individuals and their physician, with the patient understanding the information conveyed. You may also wish to look at the Macular Disease Patient Charter which provides an outline of what you, as a person with macular disease, have a right to expect! The process of arriving at an informed decision includes questions such as:
AMD Alliance International is not a medical organisation, therefore we can only provide general information that is not intended to be a substitute for a proper medical assessment. Please read our eye health information disclaimer.