Time to Clinically Significant Visual Acuity Gains after Ranibizumab Treatment for Retinal Vein Occlusion

Abstract

To assess time to first achievement of clinically significant visual acuity (VA) gains from baseline in patients with retinal vein occlusion (RVO) receiving ranibizumab versus sham treatment.Post hoc analyses of 2 phase 3 clinical trials assessing efficacy and safety of ranibizumab in patients with branch RVO (Ranibizumab for the Treatment of Macular Edema following Branch Retinal Vein Occlusion: Evaluation of Efficacy and Safety [BRAVO] study; NCT00061594) and central RVO (Ranibizumab for the Treatment of Macular Edema after Central Retinal Vein Occlusion Study: Evaluation of Efficacy and Safety [CRUISE]; NCT00056836) over 12 months.Seven hundred eighty-nine patients (BRAVO, n = 397; CRUISE, n = 392).Randomization to monthly intraocular ranibizumab injections (0.3 mg/0.5 mg) or sham. After 6 monthly injections (treatment period), patients meeting prespecified criteria received as-needed (pro re nata [PRN]) ranibizumab at their assigned dose (sham patients, ranibizumab 0.5 mg) through month 12 (observation period). BRAVO patients meeting specific eligibility criteria could receive rescue laser treatment once during the treatment and once during the observation periods.Time to first gain of 15 letters or more from baseline, analyzed using Kaplan-Meier methods. To evaluate the effect of delaying ranibizumab treatment, sham patients' VA data also were analyzed, with month 6 considered as baseline to assess vision gains during the 6 months of receiving ranibizumab PRN.Median time to first 15-letter or more gain from baseline was 12.0 (sham), 4.8 (ranibizumab 0.3 mg), and 4.0 months (ranibizumab 0.5 mg) in BRAVO and 12.2, 5.9, and 5.2 months, respectively, in CRUISE. The cumulative proportion of patients who had ever gained 15 letters or more from baseline by month 12 was 50% (sham), 68% (ranibizumab 0.3 mg), and 71% (ranibizumab 0.5 mg) in BRAVO and 42%, 61%, and 66%, respectively, in CRUISE. After 6 months of ranibizumab PRN treatment, a cumulative 10.8% (BRAVO) and 26.2% (CRUISE) of initially sham-treated patients ever gained 15 letters or more.This retrospective analysis shows that more than 50% of patients treated with monthly ranibizumab achieved clinically significant vision gains during the initial 6 months of treatment, which largely were maintained using PRN treatment to 12 months. In comparison, less than 50% of patients initially randomized to sham (and later receiving ranibizumab 0.5 mg PRN treatment) ever achieved clinically significant vision gains. These results suggest that initiating treatment immediately after diagnosis may provide the greatest vision gains. The potential benefits of early treatment should be evaluated further in prospective clinical studies.