Geographic Atrophy (GA)

What is Geographic Atrophy?

Virtually everyone who has AMD starts off with the dry form. The hallmark of dry AMD is the buildup of drusen deposits underneath or near the central region (macula) of the retina. These deposits are comprised of lipids (fats) and proteins. Many people develop drusen as they age. Certain types of drusen (the soft and large types) are more likely to lead to loss of retinal cells and vision loss, a condition known as geographic atrophy.

Symptoms

Geographic Atrophy (GA) is characterized by the loss of retinal pigment epithelial (RPE) cells which provide support for photoreceptors, the cells that make vision possible, as well as degeneration of the choriocapillaris, a layer of capillaries underneath the retina. Loss of the RPE cells and the choriocapillaris ultimately lead to loss of photoreceptors and, subsequently, central vision. People with GA develop what are known as scotomas, blind spots in or near their central field of vision. The scotomas grow in the area over time, causing more central vision loss.

Risk Factors

Like all forms of AMD, GA is a complex disease with advancing age, a history of smoking, and genetics being major risk factors.

Researchers have determined that the complement system – part of the innate immune system which fights off bacteria and other pathogens – is overactive in people with AMD, putting them at risk for retinal degeneration.

Treatment

In February 2023, SYFOVRE^TM became the first FDA-approved treatment for 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.

In August 2023, Iveric Bio received FDA approval for its GA treatment 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

Several clinical trials are currently underway for emerging GA therapies. They include gene therapies, cell-based treatments, and small molecules. Listed below are articles on some of these trials. You can also visit the Geographic Atrophy section of ClinicalTrials.gov to learn about more GA therapies in clinical development.