Has your ophthalmologist recommended anti-VEGF (also known as anti-angiogenic) therapy to treat your macular degeneration, diabetic retinopathy, or other macular disease? Here, the Royal National Institute of Blind People (RNIB) explains what anti-VEGF therapy entails, how it works, and what it could mean for you.*

Anti-VEGF medicine and the macula

Anti-VEGF treatment is medicine used to block vascular endothelial growth factor (VEGF), a cellular protein that initiates the formation of new blood vessels. Many eye conditions cause new blood vessel growth (neovascularization) or swelling (edema) below the macula at the center of the retina, a light-sensitive layer at the back of the eye that allows us to see.

• When abnormal, new blood vessels or swelling occur in the macula, which allows us to see fine details in our central vision, issues arise with daily tasks such as reading and recognizing faces.

Anti-VEGF treatment is generally intended to stabilize vision and keep it from worsening. Sometimes, though, it can also improve vision and reduce distortion. 

Therapy typically must begin right away to prevent excessive damage to the macula and preserve central vision.

Complications of anti-VEGF therapy

RNIB says anti-VEGF injections carry a “very small” risk of complications, which mainly come from the injection versus the drug itself. Complications can include:

• Slight eye pain or aching lasting one-two days
• Scleral redness or bloodshot appearance that clears within one-two weeks
• Floaters that clear up within a week
• Eye soreness and grittiness

Rare complications that can include:

• Infection
• Cataract
• Detached retina
• Rise in eye pressure
• Inflammation
• Bleeding

RNIB says these complications can be treated, so permanent vision loss after anti-VEGF treatment is rare.

When to pursue anti-VEGF therapy, and what it entails

Anti-VEGF treatment is injected through the sclera, or white part of the eye, directly into the vitreous, the gel-like fluid that fills the eye. Called an intravitreal injection, the treatment is generally quick and usually painless. There may be some variations, depending on the condition the therapy is intended to treat.

• Wet AMD treatment, if required, should happen within two weeks of referral to another eye clinic or the hospital. Treatment usually starts with a loading phase of three injections over three months, at one injection per month. Further injections are “very common” and depend on the anti-VEGF drug being used and well it works.
  
• Retinal vein occlusion-related macular edema treatment also typically begins with a loading phase of three injections over three months, spaced one injection per month. Depending on how well it’s working, more injections may be needed, which is “quite common.” Regular follow-up may be necessary for the first six months.
  
• Myopic choroidal neovascularization (mMNV) treatment typically begins with a single anti-VEGF injection, followed by monthly monitoring for the first two months. Further injections may be needed depending on progress. If stable, more injections may not be necessary, but quarterly follow-up appointments will likely be needed for the first year.
  
• Diabetic macular edema (DMO) treatment is initiated when swelling has caused a certain amount of thickening in the macula. Injections are typically monthly, possibly becoming bimonthly. The number and frequency of injections depends on the drug being administered and treatment response.

Success rate

Research shows that patients must adhere to and persist with anti-VEGF treatment for it to be successful. That said, RNIB says “[a]nti-VEGF treatments are very successful and give a good chance of preventing further sight loss.”

Degree of improvement will depend on the individual. Even though anti-VEGF can involve many injections and much follow-up, RNIB says “it is a very successful treatment and has significantly improved visual outcomes.”

*RNIB. (2022, September 1). Anti-VEGF treatment. https://www.rnib.org.uk/your-eyes/eye-conditions-az/anti-vegf-treatment