Published online Nov 12, 2015. doi: 10.5318/wjo.v5.i4.142
Peer-review started: February 22, 2015
First decision: June 3, 2015
Revised: June 23, 2015
Accepted: August 13, 2015
Article in press: August 14, 2015
Published online: November 12, 2015
Diabetic macular edema (DME) is the leading cause of blindness among working aged individuals of industrialized countries. The Early Treatment of Diabetic Retinopathy Studies (ETDRS) demonstrated that timely laser photocoagulation significantly decreases vision loss from DME, thereby establishing laser as standard- of- care for over 2 decades. Unfortunately, only a minority of patients treated in the ETDRS experienced significant improvements in visual acuity (VA), leaving researchers to look for more effective interventions. The recently introduced drugs (ranibizumab, aflibercept) that prevent the binding of vascular endothelial growth factor (VEGF) to its trans-membrane receptors produce superior improvements in VA over laser, either when administered as monotherapy or when combined with as-needed supplemental macular laser photocoagulation. The pivotal phase III trials featured monthly (ranibizumab, aflibercept) or bimonthly (aflibercept) injections of each drug for 2 years during which a significant number of patients experienced improved diabetic retinopathy (DR) severity scores. The need for anti-VEGF injections dropped significantly after 1-3 years in both the RISE/RIDE and DRCR.net Protocol I trials indicating that VEGF production had diminished. These data led to the FDA approval of both ranibizumab and aflibercept for the treatment of DR complicated by DME. Physicians may now treat vision-threatening DME with ranibizumab or aflibercept while simultaneously improving DR and possibly achieving long-term regression.
Core tip: Drugs that prevent the binding of vascular endothelial growth factor (VEGF) produce greater gains in best corrected visual than can be achieved with laser photocoagulation. The recently completed pivotal phase III trials showed that regular injections of ranibizumab and aflibercept over 2 years also improved the severity of diabetic retinopathy (DR). Both drugs have now been approved for the treatment of DR in patients with diabetic macular edema (DME) thereby allowing physicians to consider VEGF inhibition to improve DR in patients with vision threatening DME.