Macular degeneration

Eye Injections for Macular Degeneration

New Treatments for the Untreatable: Eye Injections for Dry Age-Related Macular Degeneration

Across developed countries, age-related macular degeneration (AMD) is responsible for the greatest number of cases of irreversible blindness. In the US, studies have found that around one in 10 Americans over the age of 50 years old have early-stage AMD, and one in 100 are at risk of vision loss from late-stage AMD. That’s a lot of Americans. Until this year, 2023, there have been no treatments available for the dry form of AMD, only for the wet form.

What is AMD?

Age-related macular degeneration is a disease of the macula of the eye. The macula is a highly specialized area of the retina, responsible for discriminating fine detail, such as writing and recognizing faces, and also for discerning color.

During AMD, toxic debris builds up within the retina. This leads to inflammation and damage to various cells, which ultimately result in vision loss in that part of the retina. Scientists still don’t fully understand what causes AMD – a number of underlying reasons have been suggested, including genetic factors, oxidative stress, environmental factors, inflammation, or poor blood circulation.

There are two types of AMD, the dry or geographic atrophy form, and the wet or neovascular form. Though the dry form is often a slow burn type of disease and the wet form is more of a suddenly-wake-up blind sort of situation, both can be bad.

During late-stage dry AMD, a progressive loss of retinal cells from metabolic waste accumulation results in a growing area of non-functioning retina (read: areas of retina that don’t see anymore). Early stages of dry AMD can be entirely symptomatic, while moderate dry AMD can result in symptoms such as distorted vision and a mild loss of clarity. Wet AMD is defined by the formation of new, abnormal blood vessels in the retina. These vessels can leak, resulting in further toxicity to the retinal tissues, or can also result in large hemorrhages.

Treating the Untreatable

Until very recently, only wet AMD had a treatment. Not a cure, mind you, just a treatment, in the form of eye injections to slow or delay the progression of the disease. Though some studies reported a small gain of visual acuity, the purpose of these drugs was to control the abnormal blood vessels, but typically, any damage done was considered done.

For dry AMD, doctors could only recommend lifestyle modifications, such as a diet rich in antioxidants, quit smoking, and limit alcohol. And exercise, because exercise is good for everything. A specific nutritional formulation called the AREDS2 was also found to be beneficial for some people with dry AMD.

However, the eyecare world is now excited with two new drugs FDA-approved in 2023 for the treatment of geographic atrophy from dry AMD. The first is a drug called pegcetacoplan (or Syfovre), which was approved by the US FDA on the 17th of February 2023. The second drug, avacincaptad pegol (or Izervay), was granted approval on August 4th. Similar to the medications for wet AMD, both drugs are delivered to the eye via injections, repeated at tailored intervals long-term.

Syfovre and Izervay target different inflammatory proteins that play a role in the development of geographic atrophy. Clinical trials have demonstrated a meaningful slowing of the progression of the disease, however, neither have been able to restore vision.

As with most drugs, these novel treatments are not without their risk of side effects. Potential adverse effects include increased eye pressure, blurred vision, developing wet AMD, and severe inflammation.

I Have Dry AMD, Should I Be Getting Injections?

Not everyone with dry AMD will have geographic atrophy, which is what Syfovre and Izervay are approved for. Your ophthalmologist will be able to advise whether your condition is suitable for treatment with either of these drugs.

In the meantime, the AREDS2 nutritional supplement, a diet high in antioxidants (especially two known as lutein and zeaxanthin), quitting smoking, and limiting alcohol consumption will help to preserve your maculae. And exercise, don’t forget exercise.