Purpose: Assessment of biological effect, visual acuity changes, and safety of intravitreal (IVT) ranibizumab in patients with macular edema associated with perfused central retinal vein occlusion (CRVO).
Design: Ongoing, prospective, open-label, single-center, uncontrolled study.
Participants: Ten adult patients with macular edema associated with perfused CRVO.
Methods: Patients were randomly assigned to receive 3 monthly IVT injections of either 0.3 or 0.5 mg ranibizumab (n = 5 at each dose). Additional injections were administered quarterly as needed over the ensuing 21 months at the physician's discretion for recurrent or persistent macular edema.
Main outcome measures: The predetermined primary endpoint was the percentage of patients gaining >or=15 letters of best-corrected Early Treatment of Diabetic Retinopathy Study visual acuity (BCVA). The secondary endpoints include the mean change in BCVA and central retinal thickness (CRT) measured by optical coherence tomography, the rate of progression to ischemic CRVO, extent of intraocular hemorrhage, retinal vein diameter, optic nerve head swelling, and the incidence and severity of ocular and nonocular adverse events.
Results: After 3, 6, and 9 months of follow-up, 40%, 10%, and 30% of patients, respectively, gained >or=15 letters in BCVA; mean BCVA improved by 12+/-20 letters, 3+/-21 letters, and 1+/-24 letters, respectively, compared with baseline; CRT showed a mean decrease of 272+/-244 microm, 88+/-178 microm, and 119+/-153 microm, compared with baseline. No significant differences were observed between the 0.3- and 0.5-mg doses. Most patients experienced decreases in the extent of retinal hemorrhage, retinal vein diameter, and optic nerve head swelling at months 3 and 6 compared with baseline. No patients progressed to ischemic CRVO or experienced a severe adverse event that was attributed to ranibizumab.
Conclusions: Ranibizumab is generally well-tolerated and may improve BCVA and decrease CRT. The improvements in BCVA and CRT observed during the initial monthly injection period (0 to 3 months) were possibly lost to the recurrence of macular edema in between ranibizumab injection during the quarterly treatments (3 to 9 months). The extent of retinal hemorrhage, retinal vein diameter, and nerve swelling continued to normalize for most of the patients from baseline to 6 months. Follow-up is ongoing, and alternative dosing regimens are being evaluated.