Study of Comparative Treatments for Retinal Vein Occlusion 2 (SCORE2)

Inclusion Criteria

• Participants must have center-involved macular edema secondary to CRVO. Eyes may be enrolled as early as the time of diagnosis of the macular edema. The definition of CRVO used in SCORE will also be used for the purposes of SCORE2: a CRVO is defined as an eye that has retinal hemorrhage or other biomicroscopic evidence of retinal vein occlusion (e.g., telangiectatic capillary bed) and a dilated venous system (or previously dilated venous system) in all 4 quadrants.
• Due to the similarities of a hemiretinal vein occlusion (HRVO) to CRVO,HRVO will be classified as CRVO for the purposes of this clinical trial. Eyes classified as having a HRVO will be limited to no more than 25% of the planned sample size. A HRVO is defined as an eye that has retinal hemorrhage or other biomicroscopic evidence of retinal vein occlusion (e.g. telangiectatic capillary bed) and a dilated venous system (or previously dilated venous system) in 5 or more clock hours but less than all 4 quadrants. Typically, a HRVO is a retinal vein occlusion that involves 2 altitudinal quadrants.
• E-Early Treatment Diabetic Retinopathy Study (ETDRS)visual acuity score of greater than or equal to 19 letters (approximately 20/400) and less than or equal to 73 letters (approximately 20/40) by the ETDRS visual acuity protocol. The investigator must believe that a study eye with visual acuity between 19 and 33 letters is perfused.
• Retinal thickness on SD-OCT measurement, defined as central subfield thickness of 300 µm or greater. If the SD-OCT measurement is taken from a Heidelberg Spectralis Machine, the central subfield thickness should be 320 µm or greater.
• Media clarity, pupillary dilation and participant cooperation sufficient for adequate fundus photographs.

Exclusion Criteria

• A condition that, in the opinion of the investigator, would preclude participation in the study (e.g., chronic alcoholism or drug abuse, personality disorder or use of major tranquilizers indicating difficulty in long term follow-up, likelihood of survival of less than 12 months).
• Participation in an investigational trial within 30 days of study entry that involved treatment with any drug that has not received regulatory approval at time of study entry.
• History of allergy to any anti-VEGF agent, corticosteroid, or component of the delivery vehicle.
• The participant will be moving out of the area of the clinical site to an area not covered by another clinical site during the 12 months of the study.
• Positive urine pregnancy test: all women of childbearing potential (those who are pre-menopausal and not surgically sterilized) may participate only if they have a negative urine pregnancy test, and if they do not intend to become pregnant during the timeframe of the study. Women who are sexually active with a male partner must agree to use at least one of the following birth control methods: hormonal therapy such as oral, implantable or injectable chemical contraceptives; mechanical therapy such as spermicide in conjunction with a barrier such as a condom or diaphragm; intrauterine device (IUD); or surgical sterilization of partner.
• Women who are breast-feeding.
• Examination evidence of vitreoretinal interface disease (e.g., vitreomacular traction, epiretinal membrane), either on clinical examination or OCT thought to be contributing to macular edema.
• An eye that, in the investigator's opinion, would not benefit from resolution of macular edema such as eyes with foveal atrophy, dense pigmentary changes or dense subfoveal hard exudates.
• Presence of an ocular condition that, in the opinion of the investigator, might affect macular edema or alter visual acuity during the course of the study (e.g., age-related macular degeneration, uveitis or other ocular inflammatory disease, neovascular glaucoma, iris neovascularization, Irvine-Gass Syndrome, prior macula-off rhegmatogenous retinal detachment).
• Presence of a substantial cataract that, in the opinion of th