Avastin is the brand name for a medication called bevacizumab. Bevacizumab is a type of anti-angiogenic drug, specifically classified as a vascular endothelial growth factor (VEGF) inhibitor. It is primarily used as a treatment for certain types of cancer and various eye conditions.
In cancer treatment, Avastin is often used to inhibit the growth of blood vessels that supply nutrients to tumors. By blocking the action of VEGF, which plays a role in the formation of new blood vessels, Avastin can help slow down or prevent the growth of blood vessels within tumors. This can be beneficial in limiting the blood supply to cancer cells, thereby impeding their ability to grow and spread.
In ophthalmology, bevacizumab (Avastin) is sometimes used off-label to treat certain eye conditions characterized by abnormal blood vessel growth, such as age-related macular degeneration (AMD), diabetic retinopathy, and macular edema. The medication is injected directly into the eye (intravitreal injection) to target and inhibit the abnormal blood vessel growth associated with these conditions.
It’s important to note that the use of Avastin for eye conditions is considered off-label, meaning that it is not specifically approved by regulatory authorities for these indications. Nevertheless, it is used by most eye care professionals as an alternative to other anti-VEGF medications that are specifically approved for ophthalmic use.
Avastin, like all anti-VEGF medications is injected into the vitreous cavity. The medicine wears off and needs to be injected monthly at first. After the first several injections, some patients continue monthly treatment, some patient are treated at increasing intervals and some patients are checked monthly and treated as needed. The initial studies comparing Avastin to Lucentis showed the Avastin is most effective if given monthly.
Intravitreal Injections
There have been a few studies comparing the effect of Avastin to that of Lucentis and Eylea in common retinal conditions. These results show that Avastin is as good as Lucentis when administered monthly and slightly inferior when administered less than monthly in wet macular degeneration. Additional results show that Avastin is similar to Eylea in diabetic macular edema, except perhaps in patients with very severe disease (as of this writing in January 2018). The results of the CATT study comparing Avastin to Lucentis in wet macular degeneration are shown in the accompanying graph.
Avastin (bevacizumab) is primarily used to treat various retinal diseases characterized by abnormal blood vessel growth, particularly those involving vascular endothelial growth factor (VEGF). Some of the retinal diseases for which Avastin is used include:
- Wet Age-Related Macular Degeneration (AMD): Avastin is commonly employed for the treatment of wet AMD. In this condition, abnormal blood vessels grow beneath the retina, leading to vision impairment. By inhibiting VEGF, Avastin helps reduce the growth of these blood vessels and can slow the progression of wet AMD.
- Diabetic Macular Edema (DME): Avastin is sometimes used to treat diabetic macular edema, a complication of diabetic retinopathy where fluid accumulates in the macula, causing swelling and vision problems. Inhibition of VEGF can help reduce vascular permeability and fluid leakage.
- Proliferative Diabetic Retinopathy (PDR): Avastin may be used in the treatment of proliferative diabetic retinopathy, a severe form of diabetic retinopathy characterized by the growth of abnormal blood vessels on the retina. By inhibiting VEGF, Avastin can help control neovascularization.
- Retinal Vein Occlusion (RVO): Avastin is employed in some cases of retinal vein occlusion, where there is a blockage in the veins that drain blood from the retina. The abnormal blood vessel growth associated with RVO can be targeted by inhibiting VEGF.
- Choroidal Neovascularization (CNV): Avastin is used to treat choroidal neovascularization, which can occur in various conditions, including myopic macular degeneration and other choroidal vascular diseases. Avastin helps control the growth of abnormal blood vessels in the choroid.
It’s important to note that while Avastin is widely used for these retinal conditions, its use for some eye diseases is considered off-label. This means that it has not been specifically approved by regulatory authorities for certain ocular indications, but its efficacy has been studied and reported in medical literature.
Treatment decisions should be made in consultation with an ophthalmologist or retinal specialist, taking into consideration the specific characteristics of the individual’s eye condition and their overall health.