WHAT IS AGE-RELATED MACULAR DEGENERATION (AMD)?
Age-related macular degeneration (AMD) is a very common degenerative disease of the retina, the light-sensitive tissue in the back of the eye that helps process visual information. It occurs when aging damages the macula, the region within the retina responsible for clear central vision.
There are two types of AMD, commonly referred to as “wet” and “dry.”
Wet AMD
Around 10-20% of people with AMD have wet AMD, an advanced form of AMD. Although less common, it is much more serious because it can lead to permanent vision loss quickly if not treated.
In wet AMD, the retina produces a protein called VEGF to stimulate the growth of new blood vessels (neovascularization). When there is too much VEGF, abnormal blood vessels grow in the layer beneath the retina, the choroid. The presence of the resulting choroidal neovascularization is what defines the wet form of AMD. These blood vessels are abnormal, grow underneath the macula and leak fluid into the macula, resulting in visual distortion and acute vision loss. If untreated or inadequately treated, wet AMD leads to scar formation and permanent damage that results in blindness.
CURRENT TREATMENT AND LIMITATIONS
The goal of treatment is to maintain functional vision to the greatest extent possible for the greatest duration possible.
Current standard of care for wet AMD targets the protein VEGF and requires injections in the eye every 4 to 8 weeks with some patients able to extend beyond 8 weeks. Newer treatments are becoming available that provide every 12 to 16-week dosing for some patients in clinical studies. These treatment intervals have yet to be validated in the real-world, however. In addition to a high treatment burden, many patients with wet AMD do not respond well to anti-VEGF treatment alone, even with frequent dosing.