Age-related Macular Degeneration (AMD)

AMD is a leading cause of vision loss in people over the age of 50 in the industrialized world. Symptoms of AMD include blurred or distorted central vision and black spots (scotomas).

There are two forms of AMD – dry and wet. Dry AMD accounts for nearly 85 to 90% of all cases and represents the earliest stages of AMD and is caused by fatty deposits (drusen) in the central retina, called the macula, and often not associated with any vision loss.

About 10 to 15% of patients with dry AMD progress to wet AMD. Wet AMD occurs in later stages of AMD where new blood vessels (neovascular) abnormally form in the back of the retina (choroid) – a process referred to as angiogenesis.  These neovascular blood vessels can leak fluid (edema) causing swelling of the retinal tissue and/or bleed abnormally. A potential consequence is the development of irreversible scar tissue and vision loss.

While wet AMD constitutes only 10-15% of all cases of AMD, it accounts for more than 90% of permanent vision-loss in patients with AMD. Risk factors include smoking, obesity, family history, and race. Despite the availability of anti-VEGF drugs to treat nAMD, many patients have only partial response and require frequent injections. An unmet need exists for newer treatments that can improve efficacy and durability of response.

The Normal Retina

Cross-section of a normal retina

Fundoscopic image of a normal retina.  The optic disk (optic nerve) is located in the 3 o’clock position with the normal arcade of retinal blood vessels.  The macula is in the center of the image. 

Cross-section of a normal retina using optical coherence tomography (OCT) imaging showing the natural depression or divot of the center of the macula.

Retina with Wet AMD

Cross-section of a retina with wet AMD showing retinal thickening (gray area) due to swelling and focal area of bleeding (hemorrhage).

Fundoscopic image shows multiple areas of bleeding.

OCT image demonstrates an abnormally thickened and distorted macula with fluid accumulation.