Vascular endothelial growth factor (VEGF) is a protein that produces new blood vessels in the body. Body cells are responsible for the production of VEGF. Sometimes the cells can produce excess VEGF giving rise to the growth of abnormal blood vessels in the eye. These abnormal blood vessels may damage the eye leading to low vision or blindness. Anti-VEGF drugs are used to treat some of the resultant conditions to restore vision.
There are three types of anti-VEGF treatments:
- Avastin - Avastin is the brand name for the drug bevacizumab. The drug is considered ‘off label' for the treatment of the eye because it has been approved by the Food and Drug Administration (FDA) to treat some types of cancer and not eyes. Studies have shown the drug to be useful in the treatment of the eye.
- Lucentis - Also known as ranibizumab, Lucentis is equally effective in slowing down vision loss.
- Eylea - The generic name for Eylea is aflibercept. Eylea belongs to a group of medicines called VEGF-A and placental growth factor (PlGF) antagonists. It stops the growth of abnormal blood vessels and leakage in the eye.
These three medicines are safe and effective for treating retinal diseases. The only difference comes in the packaging and cost.
Anti-VEGF medications are used in the treatment of diseases affecting the retina such as wet age-related macular edema (AMD). Other conditions treated by anti-VEGF treatments include macular edema, diabetic retinopathy and retinal vein occlusion. It is estimated that about a third of the patients on anti-VEGF treatment experience improved vision while 90% eventually register stability in their vision.
An eye doctor injects anti-VEGF drugs into the eye. The dosage depends on the drug and the condition. For example, Avastin medication is administered at 4-6 weeks intervals. Adults are given 1.25 mg in 0.05 ml of Avastin while babies receive half of that dose. In certain situations, doctors may recommend more doses.
Eylea treatment consists of a dose of 2 mg (0.05 ml) of Eylea for treating AMD. It is administered monthly for the first three months then once every two months. For macular edema, patients take 2 mg (0.05 ml) of Eylea monthly.
Anti-VEGF medications may have the following side effects:
- Eye infection
- Pain in the eye
- Itchy or dry eye
- Redness in the eye
- Injection site bleeding
- Double or blurry vision
- Extra sensitivity to light
- Intraocular inflammation
- Seeing floaters in the eye
- Conjunctival hemorrhage
- Increase in intraocular pressure
- Feeling that there is a foreign body in the eye
- Cataract (clouding of one or both clear lens of the eye) development
- Retina detachment (when the retina pulls away from the back of the eye)
Blepharitis (presence of bacteria or oily flakes on the base of the eyelashes causing red eyes, a burning sensation and swelling)
Anti-VEGF treatments may interact with some other medicines and health-related products. These include herbal supplements, vitamins, nutritional supplements, over the counter medications, etc. It is imperative that the patient discloses any medications they are using to the doctor.
Avastin may also interact with other drugs such as sunitinib and palifermin. These two drugs interact the most with Avastin and should be avoided. Palifermin should not be administered within 24 hours of the patient taking Avastin. Individuals on cholera vaccine should not take Avastin since it decreases the effects of the vaccine. Other drugs known to interact with bevacizumab include daunorubicin, doxorubicin, epirubicin, idarubicin, siponimod, paclitaxel, etc.
There are no known interactions associated with Eylea but care must be exercised when on multiple medications.
Lucentis increases the toxicity of verteporfin and presents a severe risk of intraocular inflammation.
Anti-VEGF drugs are stored at the doctor's office. The drugs stay in a refrigerator at 2 to 8 degrees centigrade. They should not be frozen and should be stored in the original carton until their time of use. Allowing the drugs to stay in the box protects them from light. These medicines should also not be used beyond the date indicated on the carton and container label. If upon opening the drugs are discovered to contain particulate matter, are discolored or cloudy, then they should be discarded.