What is the management and treatment for geographic atrophy of the retina?

Management and Treatment for Geographic Atrophy of the Retina

Currently, there are two FDA-approved treatments for geographic atrophy (GA): Syfovre (pegcetacoplan) and Izervay (avacincaptad pegol), which can slow the progression of GA lesions but do not cure the condition. 1, 2

Understanding Geographic Atrophy

Geographic atrophy is an advanced form of age-related macular degeneration (AMD) characterized by:

• Progressive, irreversible loss of photoreceptors, retinal pigment epithelium (RPE), and underlying choriocapillaris 1
• Sharply demarcated atrophic lesions that typically appear first in the perifoveal macula 3
• Gradual expansion of lesions that may eventually involve the fovea, leading to severe central vision loss 1

Diagnostic Approach

A multimodal imaging approach is essential for accurate diagnosis and monitoring of GA:

• Optical Coherence Tomography (OCT): Primary diagnostic tool that visualizes cross-sectional retinal morphology and identifies GA lesions 4, 5
• Fundus Autofluorescence (FAF): Provides high contrast for delineation and quantification of GA areas 4
• Color Fundus Photography (CFP): Historical standard that allows comparison with past studies 4
• Near-Infrared Reflectance (NIR): Helps with precise demarcation of atrophy borders, especially near the fovea 4

For comprehensive assessment, additional imaging may include:

• Fluorescein angiography (FA) to rule out neovascularization
• Indocyanine green angiography (ICG-A) in selected cases 4

Treatment Options

FDA-Approved Treatments

1. Complement Inhibitors:
   • Pegcetacoplan (Syfovre): First FDA-approved treatment for GA; intravitreal injections that slow GA progression 1, 2
   • Avacincaptad pegol (Izervay): C5 inhibitor that reduces lesion growth rate and may reduce risk of severe vision loss 6, 2

Supportive Management

1. Nutritional Supplements:

   • AREDS2 formulation (vitamins C, E, zinc, copper, lutein, and zeaxanthin) may be beneficial in slowing progression 7

2. Low-Vision Rehabilitation:

   • Low-vision aids are considered among the most beneficial interventions for patients with GA 5
   • May include magnifiers, electronic reading devices, and adaptive technologies

3. Lifestyle Modifications:

   • Smoking cessation is crucial as smoking significantly increases AMD risk and progression 7
   • Maintain healthy body mass index
   • Eye protection from sunlight 7

Monitoring Disease Progression

Regular monitoring is essential for:

• Tracking GA lesion growth (median progression rate ~1.78 mm²/year) 3
• Detecting conversion to neovascular AMD
• Assessing functional vision changes

Recommended monitoring tools:

• Serial OCT scans
• FAF imaging for quantifying lesion size changes
• Functional assessments including:
  • Microperimetry
  • Low-luminance visual acuity
  • Reading speed assessments
  • Patient-reported outcomes 3

Prognostic Factors

Several factors can help predict disease progression:

• Baseline lesion characteristics:

  • Larger lesion size correlates with faster progression
  • Multifocal lesions tend to progress more rapidly
  • Specific FAF patterns (especially hyperautofluorescent borders) indicate faster growth 3

• Fellow eye status: Presence of advanced AMD in one eye increases risk in the other 7

• Time to foveal involvement: Median time from non-subfoveal GA to subfoveal involvement ranges from 1.4 to 2.5 years 1

Patient Education and Support

Patients should be counseled on:

• The progressive nature of GA
• Realistic expectations from treatment (slowing progression rather than restoration of vision)
• Self-monitoring with Amsler grid testing 7
• Adaptation strategies for activities of daily living
• Available support resources and low-vision services

Future Directions

Numerous clinical trials are investigating additional therapeutic approaches targeting various molecular pathways associated with GA 2. Current approved treatments provide hope but have limited efficacy, highlighting the need for more effective therapies with improved safety profiles and better patient compliance.