VEGF
Humans naturally produce a protein called vascular endothelial growth factor (VEGF), which is crucial in both the development and maintenance of blood vessels.
VEGF
What is Neuro Ophthalmology?
Humans naturally produce a protein called vascular endothelial growth factor (VEGF), which is crucial for both blood vessel development and maintenance. It forms abnormal vasculature in response to abnormal circumstances such diabetic retinopathy, blood vessel obstruction, and age-related macular degeneration, which bleed, leak, develop scar tissue, and cause vision loss.
What are anti VEGF Agents
There is a class of drugs known as anti vascular endothelial growth factor (anti VEGF) agents, which work by inhibiting VEGF’s action and reducing the protein’s negative side effects.
What are the anti VEGF Agents available for treatment
Bevacizumab
Ranibizumab
Aflibercept
Brolucizumab
How are these anti VEGF agents different from one another
| Bevacizumab | Ranibizumab | Aflibercept | Brolucizumab | |
| Molecule | Monoclonal antibody | Antibody fragment | Fusion protein | Single chain antibody |
| Molecular weight | 149 kDa | 48kDa | 97-115 kDa | 26 kDa |
| Clinical dose | 1.25 mg | 0.5 mg | 2 mg | 6 mg |
| FDA approval | Not approved | Approved | Approved | Approved |
| Intravitreal anti VEGF activity | 4 weeks | 4 weeks | Upto 12 weeks | Upto 12 weeks |
How has anti-VEGF medication changed the way different eye diseases are handled?
When used correctly, anti-VEGF medicines can reduce morbidity by blocking VEGF’s effect at the molecular level.
Treatments for diseases once thought incurable have given people the chance to keep their eyesight and, by extension, their lives. One such disease is age-related macular degeneration.
Anti VEGF drugs are now also used to treat the ocular manifestations of systemic disorders such diabetes and hypertension, resulting in improved and sustained visual acuity.
How effective are anti-VEGF drugs, and what ailments do they typically treat?
| Disease | Pathology | Benefits |
| Wet age related macular degeneration | Abnormal vessels at the back of the eye leak fluid and blood, leads to drop in vision |
Abnormal vessels regress with resorption of fluids with subsequent improvement of vision |
|
Diabetic macular edema |
Leakage of fluid due at the back of the eye leading to swelling and vision drop |
Prevent leakage and reduce swelling |
| Proliferative diabetic retinopathy |
Abnormal vessels on the retina which bleed |
Regression of abnormal vessels |
| Retinal vein occlusion | Swelling of retina due to obstruction of retinal blood vessels |
Resolution of swelling with improvement of vision |
How do I choose the type of anti VEGF agent:
Your physician will prescribe the most effective medications for your specific condition after assessing your overall health and disease progression. Macula bleeding or leakage is an emergency situation that requires prompt medical attention. The doctor will run the necessary scans to confirm, measure, and track the disease’s development. One of the indicators of therapy success is visual acuity.
How is the anti-VEGF agent administered:
- After clinical examination and relevant scans and making a diagnosis, the doctor will discuss the available options with the patient.
- The anti-VEGF agent is administered into the eye by means of a fine needle under sterile conditions in an operation theater.
- The eyes are numbed with topical anaesthetic agent
Cleaning of eyes and surrounding structures with an antiseptic solution is done. - Protective sheet called eye drape is applied around the eye.
- Eyelids are opened with a clip called an eyelid speculum
The doctor injects the drug through the white part of the eye through a fine needle. - After injection, gentle massage is done at the site of injection.
- The eye clip is removed, and antibiotic drops are instilled in the eye
Antibiotic drops are prescribed for usage after injection in the eye.
What are the anti-VEGF agents available for treatment?
- Bevacizumab
- Ranibizumab
- Aflibercept
- Brolucizumab