Anti VEGF Injection therapy for retinal vascular diseases
Introduction:
Anti-VEGF therapy, introduced to ophthalmology less than a decade ago, has fast become a mainstay of managing diseases such as age-related macular degeneration and may expand to even more indications.
Ophthalmology has witnessed an explosion in the number of intravitreal injections delivered to patients over the past 10 years, driven in large part by the introduction and rapid incorporation of anti-VEGF therapy. Medical management of retinal diseases has arguably come to dominate clinical practice and, to some experts, has resulted in better delivery of patient care.
The role of vascular endothelial growth factor in the growth of both regular and abnormal blood vessels was identified in the 1980s, and agents that could block the angiogenic cascade first came on the scene for cancer treatments in the early 1990s.
Nearly a decade later, researchers who were looking for an alternate treatment paradigm for the abnormal growth of blood vessels in the eye and the exudation of fluid from otherwise normal blood vessels began to investigate the use of anti-VEGF agents in the treatment of AMD. What resulted was a new treatment paradigm — first came Macugen (pegaptanib sodium, Eyetech/Pfizer) and later the off-label use of Avastin (bevacizumab, Genentech) followed by Lucentis (ranibizumab, Genentech) — that not only slowed vision loss or maintained current visual acuity, but also offered the potential to improve and even restore functional vision.
Use in glaucoma::
Part of the concern over IOP elevation after anti-VEGF injection is due to the increasing popularity of using these agents in various ophthalmic indications.
Historically, neovascular glaucoma was treated with a combination of medication to lower IOP and laser panretinal photocoagulation to abate angiogenesis. But “oftentimes, these patients would have to go to surgery emergently to place a glaucoma drainage device because existing therapies did not decrease IOP fast enough.
However, whereas multiple intravitreal injections of anti-VEGF agents may well be a cause of IOP elevation, anti-VEGFs have also proven invaluable in the reduction of IOP, especially due to glaucoma subtypes involving neovascularization.