Geographic Atrophy Natural History Versus Treatment: Time to Fovea

Area of Science:

• Ophthalmology
• Medical Research
• Clinical Trials

Background:

• Geographic atrophy (GA) is an advanced form of age-related macular degeneration.
• Recent FDA approvals offer new therapeutic options for GA.
• Understanding GA progression is crucial for patient management.

Purpose of the Study:

• To quantify the time for GA lesions to reach the fovea.
• To model the impact of therapeutic interventions on GA growth rates.
• To compare treatment effects against the natural history of GA progression.

Main Methods:

• Utilized published data on GA lesion border expansion rates at various eccentricities.
• Modeled GA expansion towards the fovea under different treatment scenarios.
• Simulated effects of 15% to 45% reduction in GA growth rates on lesions of varying sizes and distances from the fovea.

Main Results:

• A GA lesion 500 µm from the fovea is projected to reach the fovea in 5.08 years without treatment.
• With treatments reducing GA area growth by 15% to 45%, the same lesion's foveal reach is extended to 5.85 to 8.46 years.
• Lesion size had a minimal impact on GA growth rates toward the fovea.

Conclusions:

• The distance of a GA lesion's posterior edge to the fovea is the primary determinant of progression speed.
• GA lesion size minimally influences growth rates.
• This study provides valuable insights into the time benefit of GA treatments, aiding clinical decision-making for patients and physicians.