AMD Treatment
New research is underway to develop additional treatments for both dry AMD and wet AMD. Several pharmaceutical companies are currently conducting trials of new drugs, while non-profit organizations such as the FFB and the Canadian Institutes of Health Research are working together to speed the transition of treatments from developmen in animals to testing in human trials. Use this link to learn more about our partnerships with the Canadian Institutes of Health Research.
Dry AMD
The AREDS Formula
The only treatment that is currently available to people with dry AMD is a combination of vitamins and minerals tested in the Age-Related Eye Disease Study (AREDS). This study was funded and monitored by the National Eye Institute in the United States to ensure its reliability. Several companies now market vitamin formulations containing the vitamins tested in AREDS.
- 500 milligrams of vitamin C;
- 400 International Units of vitamin E;
- 15 milligrams of beta-carotene;
- 80 milligrams of zinc as zinc oxide;
- 2 milligrams of copper as cupric oxide.
The AREDS study found that this high-dose combination of vitamins C, E, beta-carotene, and zinc reduced by 25% the likelihood that a person with high risk dry AMD would develop more severe vision loss within the next five years. Copper is added to the formula to prevent copper deficiency anemia - a condition associated with high levels of zinc intake.
Although the AREDS formulation can be purchased without prescription, before you begin taking it, you should talk to your doctor about whether it is right for you. Some people should not take the AREDS formulation, as it can increase the risk of some urinary tract problems. Beta-carotene has also been shown to increase the risk of lung cancer in current smokers. Your doctor can help you weigh the risks of using the AREDS formulation.
The AREDS formulation is the only nutritional treatment with clear scientific evidence showing its benefit for people with AMD. However, there is some evidence that other nutrients, particularly lutein and zeaxanthin, may be beneficial. As noted in the prevention section, there is also some evidence that fish oils, which contain omega-3 fatty acids, may be protective. The AREDS-2 study, now underway, will attempt to determine whether a better AREDS formulation might include these nutrients and whether the amounts of some of the original nutrients should be adjusted.
Emerging Options
- oral medications,
- treatments implanted or injected into the eye, and
- topical medications or drops
You can learn more about these ongoing trials in our research section. None of these options is currently approved for use in Canada.
For people with very advanced vision loss due to AMD, a new implantable telescope device was recently approved for use in the United States. This implant does not cure the underlying damage to the retina or slow down the disease. It is a magnifier that helps the wearer to read and see fine details more easily, leaving both hands free and minimizing the outward signs of visual impairment. This technology is not currently approved in Canada.
Wet AMD
For people diagnosed with wet AMD, these treatments can slow or stop vision loss, and may even help restore vision in some cases.
Anti VEGF
Over the past five years, it has become possible to treat wet AMD with any of several new drugs called anti-VEGF agents. Vascular endothelial growth factor (VEGF) is a substance normally produced by our bodies to tell new blood vessels to form, as when a wound is healing. However, in wet AMD, the tiny blood vessels at the back of the eyes often grow uncontrollably, leaking fluids, and causing vision loss. Anti-VEGF agents counteract that process. They are injected periodically into the affected eye to slow the growth of blood vessels and prevent vision loss. In some cases, they can even reverse the effects of the disease.
Macugen (pegaptanib) was the first such drug approved to treat wet AMD, in April 2006. It tends to stabilize vision loss rather than improve it. Lucentis (ranibizumab), which was approved in 2007, can stabilize vision loss and, in some cases, restore some vision. Both treatments are administered via injections into the eye, with initial treatment usually given monthly.
Some ophthalmologists will use Avastin (bevacizumab) to treat wet AMD instead of Lucentis, because it is chemically similar to Lucentis, acts in the same way, and is a cheaper alternative for most patients. Avastin is currently approved in Canada to treat metastatic lung and colorectal cancer, but the results of controlled clinical trials to validate the use of Avastin in AMD are not yet available. A number of small studies supporting the safe and effective use of Avastin for wet AMD have been reported. To further clarify this issue, a large clinical trial involving 1200 patients in the United States is now under way comparing Lucentis to Avastin. Please speak to your doctor about the best treatment option for you.
Photodynamic Therapy
In photodynamic therapy a light-sensitive drug is given to the patient intravenously. Currently the only drug approved to treat AMD in this way is verteporfin (Visudyne), a drug developed by the Canadian company QLT Inc (although others are being tested). After the drug has circulated through the system, a cold (non-thermal) laser is focused on the abnormal blood vessels in the eye. This activates the drug and destroys the abnormal vessels. Unlike laser photocoagulation (below), it does not cause a blind spot. Photodynamic therapy affects only the injected drug, and because the drug is confined mainly to the abnormal new blood vessels, it causes little damage to the surrounding tissue. However, people who have this therapy must avoid the sun for several days to prevent the drug from being activited elsewhere in the body and causing damage to light exposed skin. Photodynamic therapy can be performed on an outpatient basis, and repeated as needed. Trials exploring whether photodynamic therapy and anti-VEGF treatments can be combined for better outcomes have largely failed to show a benefit for combination therapy.
Laser Photocoagulation
Laser photocoagulation uses tiny laser beams shone into the eye to seal leaky blood vessels and slow their growth. In the 1990’s this was the only therapy available for AMD, but with the availability of drug therapies for wet AMD it is rarely used today. When this laser light is absorbed by the eye it turns to heat, sealing abnormal vessels and preventing further vision deterioration. However the treatment also creates a scar, and thus creates a permanent blind spot in the field of vision. Vision does not usually improve after laser treatment and may even be somewhat worse due to scar formation; however, it is generally prefereable to no treatment at all. In many cases, some visual distortion will disappear after laser treatment.
New drugs and therapeutic approaches are also being tested for wet AMD. Use these links to learn more about new clinical trials for wet AMD and about the AMD research being supported by your donations to the Foundation Fighting Blindness.
Updated: Sept 15, 2010. This section has been reviewed by Dr. Peter Kertes, Associate Professor of Ophthalmology and Vision Sciences at the University of Toronto and Dr. William Stell, FFB Director of Research Programs and Professor of Ophthalmology at the University of Calgary.
Learn more about AMD: |
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| What is AMD? | Risk Factors for AMD |
| Early Detection | Early Detection |
| AMD Research | Frequently Asked Questions |