VEGF Trap Eye (Eylea)
Eylea ( aflibercept) is an Intravitreal injection that can be used in patients with Wet Macular degeneration and also in patients with macular edema and new blood vessels due to diabetic retinopathy and central retinal vein occlusions. This is a new medication that can be added to the list of Anti VEGF such as Ranibizumab (Lucentis) and Bevacizumab (Avastin).
On April 18, 2011, U.S. Food and Drug Administration (FDA) has accepted for review the Biologics License Application (BLA) for VEGF Trap-Eye for the treatment of the neovascular form of age-related macular degeneration (Wet AMD)and it was approved for that on November, 2011.
On September 2012, it was approved for the treatment of macular edema that is caused by central retinal vein occlusion.
VEGF Trap Eye (aflibercept) is ultrapurified protein that is made from domains part of Human VEGF receptors 1 and 2. These parts are fused with Fc part of Human AB (IgG1).
It acts like natural VEGF receptor and binds with higher affinity than their natural receptors to all forms of VEGF-A and also to Placental Growth Factors (PlGF). In order to be suitable for intraocular injection, it is especially purified and contains iso-osmotic buffer concentration.
What are VEGF and PIGF?
Vascular Endothelial Growth Factor (VEGF) and Placental Growth Factor (P1GF) are natural growth factors that have normal roles in formation of healthy blood vessels in different tissues and organs but in the back of the eye, these two growth factors were found to cause the growth of abnormal blood vessels or neovascularization in patients with Age-Related Macular Degeneration, Diabetes Mellitus and Central Retinal Vein Occlusions. They also increase permeability of blood vessels which causes Edema.
Trap Eye molecules have higher affinity to bind these factors than the natural receptors in the retina. Once these growth factors are bonded to VEGF Trap molecules, their actions to form new fragile blood vessels and increase vascular permeability are inhibited or blocked.
What are the differences between Trap eye and current Anti-VEGF injections (Avastin and Lucentis) ?
1- Trap Eye (Eylea) blocks that action of Placental Growth Factors (PlGF) which are not blocked by the current Anti-VEGF medications.
2- Current Anti-VEGF medications are rapidly cleared from the eye while Trap Eye complex is relatively inert, and is degraded more slowly which may lead to longer duration of action.