This is an injection medicine used to treat wet macular degeneration and sometimes used for other causes of macular edema such as diabetic retinopathy. Avastin was originally developed for systemic use to treat colon cancer. However, its anti-VEGF properties are good at targeting abnormal retinal blood vessels and so it is commonly used in the eye as well. Avastin is a wonder drug, and compared to comparable injectables (Lucentis, Macugen, Eylea), it is extremely cheap. The reason behind this cost is that Avastin was originally packaged in much larger dosage for systemic delivery for the entire body. Compounding pharmacies can split this large dosage into increments more suitable for ocular injection and the cost comes down to about 50 dollars a treatment. Compare this to medicines approved and marketed specifically for the eye which cost around $2,000 per treatment … it makes you wonder how pharmaceuticals get away with it, huh?