Seniors with age-related macular degeneration, or AMD, may benefit from two drugs approved this year and promising treatments in development.
Around 20 million Americans suffer from macular degeneration, and about 1.5 million of those have an advanced stage of the eye disease. Most macular degeneration occurs as people grow older. Most (90%) of age-related macular degeneration (AMD) is the dry, or early, form. Yellow-white fatty deposits, called drusen, collect on the eye’s macula, at the center of the retina. Wet AMD is an advanced form responsible for only 10% of cases but 90% of blindness. It is characterized by the rapid growth of new blood vessels at the back of the eye that leak fluid into the macula.
“Vision loss can have a major impact on the quality of life for older adults. Difficulties an older adult might experience are a loss of independence and no longer being able to drive or go places without assistance. This increases the risk of social isolation and loneliness,” says Rebecca Boxer, chief of the UC Davis Health Division of Geriatrics, Hospice and Palliative Medicine. “Additionally, loss of vision increases the risk of falls and injury.”
Who’s More at Risk of AMD?
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You may not realize you have AMD in its early form. If only one eye has dry AMD, there may be no change in vision. That’s why it’s so important to get an annual dilated eye exam. When and if dry AMD progresses to wet AMD, you’ll notice sudden blurred vision, blind spots in the middle of your visual field, trouble distinguishing colors, difficulty seeing in low light and edges and lines will appear wavy.
Standard Treatment for AMD
Dry AMD in its early and intermediate forms can sometimes be slowed by taking a combination of antioxidant vitamins known as AREDS 2.
Wet AMD is usually treated with periodic eye injections. One, Avastin, inhibits the growth of blood vessels. Several others work to bind and inhibit excess protein produced in the retinas of some people with AMD. These drugs stabilize or improve vision in the majority of patients, but the injections must be given every four to 12 weeks, a difficult ask for many older adults who may have other conditions to manage and/or difficulty accessing transportation to a doctor’s office.
A newer drug, brand-named Vabysmo, targets two proteins instead of just one. It is also given via eye injection, but it lasts longer than other treatments. Patients typically go from three to four months between shots. A similar option that’s in phase III (final phase) clinical trials is Opthea’s OPT-302. The drug has been dubbed Sozinibercept and should be on the market soon.
Finally, certain people with wet AMD can be treated with laser photocoagulation. It may be an option if your abnormal blood vessels are in a tight bunch, ideally away from the central area of the macula. Usually, the best candidates had vision loss that occurred suddenly, not slowly. In the surgery, an intense light beam is used to burn tiny areas of the macula to seal off leaky vessels. It doesn’t always restore vision, but it can delay further loss of sight.
Two New Treatments for Late Stage Dry AMD
The third and final stage of dry AMD is called the late stage, or geographic atrophy, when the macula degenerates. Until recently, there was no treatment for those living with this stage of the disease. In February of this year, the Food and Drug Administration (FDA) approved the first medication, called Syfovre, to treat geographic atrophy. Created by Apellis Pharmaceuticals, the active ingredient in Syfovre is Pegcetacoplan. The drug is injected in the eye, usually on a monthly plan. Research indicates that it works best when taken over time, slowing the disease and retarding the degeneration of the retina.
In August, Izervay (avacincaptad pegol) became the second drug to be cleared by the FDA for late stage dry AMD. The drug works by blocking the complement C5 protein, reducing the rate of breakdown in retinal cells. Clinical trials by drugmaker Astrellis indicate treatments with Izervay began to show results within six months and displayed up to a 35% reduction in the progression of geographic atrophy at the one year mark. Izervay is delivered by injection directly into the eye.
On the Horizon
People with wet AMD may soon benefit from ongoing experimental gene therapy. RGX-314 is a treatment that targets the unwanted protein, vascular endothelial growth factor (VEGF). The treatment is delivered via the injection, under the retina, of a virus that carries the anti-VEGF gene. It’s in phase III clinical trials. The truly exciting thing about this treatment is that it has the potential to keep working for years following the initial surgical procedure.
Cell therapy involves the injection of cells into your body to replace damaged, depleted or missing cells. Stem cells are able to grow or change into any type of cell. They’re already used to treat many diseases, including retinal disorders. Typically, a certain type of stem cell is harvested from the patient, then instructed to become the desired cell type or precursor. It’s then injected into the eye to replace or generate damaged cells.
An induced pluripotent stem cell is one that is also taken from the patient, then reverted into an embryonic stem cell that can become any sort of cell in the body. Stem cells that come from the patient originally are less likely to be rejected.
Clinical trials for cell therapy to treat geographic atrophy are ongoing in the US and other countries. A current trial to treat late stage dry AMD involves OpRegen. It’s testing the safety of and tolerance for embryonic stem cell-derived retinal pigment epithelium cells. So far, results are promising.
AMD strikes many older adults and takes a high toll. Today, advances in treatment are beginning to fight back and offer seniors more options to stop this disease in its tracks. There’s hope that in five to ten years, we’ll be able to reverse the effects of at least some types of AMD.
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Blog posting provided by Society of Certified Senior Advisors
