Age-Related Macular Degeneration

What is Age-Related Macular Degeneration?

Age-related macular degeneration, commonly referred to as AMD, is a retinal degenerative disease that causes a progressive loss of central vision. AMD is a leading cause of vision loss in individuals over the age of 55 in developed countries. More than 18 million people in the United States have AMD.

The retina is packed with photoreceptors, the cells that enable us to see. Photoreceptors convert light into electrical impulses, which are transferred to the brain via the optic nerve and converted into the images we see. The macula is a small region in the center of the retina that’s rich in cones, the photoreceptors that enable a person to perceive fine details (e.g., read, recognize faces), colors, and objects in daylight or lighted conditions. Central vision loss from AMD occurs when cone photoreceptors in the macula degenerate.

The greatest risk factors for AMD are aging and smoking. An unhealthy diet and unprotected sunlight exposure can also increase AMD risk.  Genetics is also a risk factor.

Age-Related Macular Degeneration Explainer Video

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Types

AMD occurs in two forms: dry and wet. Dry AMD is the most common form, accounting for about 80-90% of cases, while wet AMD is less common but progresses more rapidly.

Symptoms

People with AMD often first notice subtle changes in their central vision. This may include blurriness during tasks like reading or sewing, or straight lines appearing distorted or wavy. As AMD progresses, blind spots can develop in the central field of vision. In most cases, if one eye has AMD, the other eye has the condition or is at risk of developing it. The extent of central vision loss varies and can depend on the type of AMD — dry or wet.

Most people with AMD start off with the dry form. In many cases, people will not experience vision loss from the condition. In some cases, dry AMD can progress and cause varying degrees of central vision loss. Advanced dry AMD is sometimes referred to as geographic atrophy (GA). 

There are three stages of AMD, and the symptoms vary by stage:

• Early stage: Typically, no symptoms.
• Intermediate stage: Sometimes mild blurriness or difficulty seeing in low light.
• Advanced stage: Vision changes become more pronounced. Symptoms may include straight lines appearing wavy, blurring or blind spots in central vision, dulling of colors, and increased difficulty with low-light vision.
  • There are two forms of advanced AMD:
    • Advanced dry AMD (also called geographic atrophy (GA)): characterized by areas of retinal cell death that gradually expand over time.
    • Advanced wet AMD (neovascular or exudative AMD): occurs when abnormal blood vessels grow under the retina and leak fluid or blood, leading to rapid vision loss if untreated.

The hallmark of dry AMD is the presence of drusen—tiny deposits of protein and fat under the retina. Many people have drusen, which do not affect vision. However, certain types of drusen may interfere with the health of the macula, causing progressive degeneration of the photoreceptor cells and vision loss.

About 10-15 percent of people with dry AMD will develop the wet form in one or both eyes. Wet AMD occurs when abnormal blood vessels grow beneath the macula. These vessels can leak fluid or blood and quickly damage photoreceptor cells, leading to rapid changes in central vision if not treated.

Inheritance

Researchers have discovered that genetics can play a role in AMD risk. In 2005, three groups of researchers, including a team funded by the Foundation, discovered that a gene called Complement Factor H (CFH) is linked to at least 50 percent of all cases of AMD. Since that breakthrough, researchers have found several other genes linked to AMD. CFH and many of the other AMD genes are involved in the innate immune system, which fights off infection. Scientists believe that over activity of the innate immune system increases AMD risk.

While genetics can play a role in AMD risk, people with low risk genetics can still get the condition. Likewise, people with high risk genetics may not get AMD.

Treatment 

The Age-Related Eye Disease Study (AREDS) — a landmark investigation conducted by the National Eye Institute (NEI) — determined that a specific antioxidant supplementation can slow the progression of AMD. The AREDS2 formulation is an over-the-counter antioxidant supplement recommended for people who are at risk of developing more advanced forms of dry or wet AMD.

The AREDS2 formulation contains the following nutrients:

500 milligrams (mg) of vitamin C
400 international units of vitamin E
80 mg zinc as zinc oxide
2 mg copper as cupric oxide
10 mg lutein and 2 mg zeaxanthin

Several therapies are now available for the wet form of AMD. Most involve regular ocular injections to halt the growth of leaky, vision-robbing blood vessels.

EYLEA™ (alflibercept) — Regeneron’s wet AMD treatment, Eylea, blocks the development of unhealthy blood vessels underneath the retina. Regeneron reports that in clinical trials, Eylea treated wet AMD as effectively as Lucentis, but with fewer intraocular injections. Typically, patients are treated monthly with Eylea for three months and every other month thereafter. Eylea was FDA-approved in 2011. Eylea HD, a high-dose and longer-acting formulation of Eylea, was approved in August 2023.

Lucentis™ (ranibizumab) — Developed by Genentech, Lucentis is effective in reducing the risk of losing vision from the abnormal blood vessel growth under the retina associated with wet AMD. The treatment was approved by the FDA and made available in 2006. A two-year study showed that 95 percent of people with wet AMD who received monthly injections of Lucentis experienced no significant loss in visual acuity from baseline. Genentech also reported moderate visual improvement in 24.8 percent of participants treated with a 0.3 mg dose of Lucentis and 33.8 percent of participants treated with a 0.5 mg dose.

A colorectal-cancer drug called Avastin® — a drug similar to Lucentis — has been used “off-label” by some ophthalmologists to treat wet AMD. The NEI completed a large-scale, two-year clinical study comparing Avastin and Lucentis. Results of the study showed that the drugs were similar in safety and efficacy.

VABYSMO™ (faricimab-svoa) – treatment for wet AMD developed by Genentech. Vabysmo is the first bispecific antibody approved for the eye and works by inhibiting two disease pathways, VEGF-A and Angiopoietin-2, both linked to abnormal blood vessel growth and leakage under the retina. In clinical trials, Vabysmo achieved vision outcomes comparable to aflibercept with the added benefit of extended dosing intervals: after four initial monthly injections, many patients can move to every 8–16 weeks. Vabysmo was FDA-approved in January 2022.

SYFOVRE^TM – the first FDA-approved treatment for geographic atrophy (GA). Developed by Apellis, the therapy slows the growth rate of the lesions (regions of retinal cell degeneration) that lead to central vision loss. SYFOVRE is injected into the middle of the eye by a retinal specialist once every 25 to 60 days. The treatment works by inhibiting the C3 protein, which is associated with an overactive and damaging innate immune system.

IZERVAY^TM – FDA-approved treatment by Astellas for GA known as IZERVAY (avacincaptad pegol), which slowed the growth rate of GA lesions in two Phase 3 clinical trials. Also injected into the middle of the eye, the treatment works by inhibiting the C5 protein, which is associated with an overactive and damaging innate immune system.

Clinical Trials

View a list of current clinical trials, many made possible by Foundation support.

AMD page at www.ClinicalTrials.gov.

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The information provided by the Foundation Fighting Blindness is for educational purposes only and is not intended as medical advice. Some of the information provided has been obtained from widely used third-party public sources, but the Foundation is unable to independently verify the accuracy of all of such information. The Foundation does not endorse any specific treatment, product, clinical trial, company, or provider, including those mentioned in our content or featured through our partners and sponsors. Every person's condition is unique. Please talk with your qualified eye care professional about the treatment options that are right for you.