Two-Year Results of the READ 2 Study: Ranibizumab for Edema of the Macula in Diabetes

Abstract

Purpose: : To describe the changes in best corrected visual acuity (BCVA) and excess retinal thickness (ERT) in subjects with 2-year follow-up in the READ 2 study, which is a phase 2, randomized clinical trial evaluating ranibizumab (RBZ) compared to focal laser or combination therapy (RBZ plus focal laser) in eyes with diabetic macular edema (DME).

Methods: : 98 out of 126 subjects completed the month-24 visit. Subjects were initially randomized 1:1:1 into one of 3 groups: RBZ 0.5mg (group 1); focal laser from baseline (BL) to month 6 (group 2) with laser or RBZ (0.5mg) after month 6; and RBZ (0.5mg) with focal laser combination therapy from BL to month 6 with continued combination therapy or monotherapy with RBZ starting after month 6 (group 3). After month 6, the decision on type of treatment was at the discretion of investigators. Re-treatment criterion for all groups starting at month 6 included central retinal thickness ≥ 250µm on optical coherence tomography (OCT).

Results: : At month 6, the primary endpoint of the study, mean change in BCVA (in letters) was +7.2 in group 1, -0.4 in group 2, and +3.8 in group 3. Starting at month 6, the majority of treatments given in all 3 groups from month 6 to 24 included monotherapy with RBZ. At month 24, the mean change in BCVA (in letters) was +7.6 in group 1, +5.0 in group 2, and +6.4 in group 3. ERT on OCT at month 24 was +125.6 µm, +75.5 µm, and +58.4 µm for groups 1, 2, and 3, respectively. There were no drug related ocular or systemic adverse events.

Conclusions: : Treatment of DME with RBZ for 24 months appears safe and results in an improvement in BCVA and a reduction in ERT on OCT. Additional studies and long-term analyses of the READ 2 study are needed to determine the optimal dosing schedule of RBZ in eyes with DME.

Clinical Trial: : www.clinicaltrials.gov NCT00407381

Keywords: diabetic retinopathy • vascular endothelial growth factor • macula/fovea