This is a phase 4 prospective, nonrandomized, open label, interventional clinical trial to determine the efficacy of intravitreal aflibercept (IAI) administered in a treat and extend fashion in eyes that have persistent centered involved diabetic macular edema despite at least 4 intravitreal injections of ranibizumab 0.3mg over 24 weeks prior to enrollment. Patients will receive intravitreal injections of aflibercept (2mg/0.05cc) at baseline and monthly until an eye has reached stability defined as: < 10% change in the Spectral Domain Optical Coherence Tomography (SD OCT) central retinal thickness (CRT) reading from the previous 2 visits (can include baseline) and less than a 5 letter decrease in Best Corrected Visual Acuity (BCVA) from best BCVA from prior visits. Once an eye has reached stability criteria, a treat and extend protocol will be used and treatment will be rendered on every visit. The duration between treatments will be extended by 2 weeks from the last visit if SD OCT extension criteria are met: < 10% change in CRT over 2 consecutive visits and < 5 letter decrease in BCVA from baseline~If at any return visit subretinal and/or intraretinal fluid recurs that causes the CRT to increase by > 10 % from its lowest level in the previous 2 consecutive visits, or CRT increases by < 10% due to subretinal and/or intraretinal fluid but is associated with a decrease of BCVA of > 5 letters from baseline then the eye will receive IAI and the treatment interval will be decreased by 1 week. If the eye has not improved or worsened for at least 2 consecutive visits and the SD OCT central subfield thickness is ≥ 300 microns or visual acuity is worse than 20/20, the following will be done:~Prior to the 24-week visit, an injection will be given. At and after the 24-week visit, an injection will be given and modified grid laser can be given at the discretion of the investigator within 7 days of IAI based on rescue criteria
The purpose of this study is to determine the efficacy of intravitreal aflibercept injections administered in a treat and extend fashion in eyes that have persistent center involved diabetic macular edema following at least 4 intravitreal injections of 0.3 mg ranibizumab over 24 weeks.