Intravitreal Bevacizumab vs Laser Therapy in the Management of DME
In this 2-year, single-center, randomized controlled trial, investigators randomized 80 patients with center-involving clinically significant macular edema (CSME) and visual acuity of 20/40 to 20/320 to receive either bevacizumab or macular laser therapy (MLT). The purpose of the study was to report the 2-year outcomes of the BOLT study, a prospective randomized controlled trial evaluating intravitreous bevacizumab and modified Early Treatment Diabetic Retinopathy Study (ETDRS) MLT in patients with persistent CSME.
Primary outcome was the difference in ETDRS best-corrected visual acuity (BCVA) between arms. Secondary outcomes were the mean change in BCVA, proportion gaining at least 15 and at least 10 ETDRS letters, losing fewer than 15 and at least 30 letters, change in central macular thickness, ETDRS retinopathy severity, and safety outcomes.
The study investigators reported that at 2 years, mean (SD) ETDRS BCVA was 64.4 (13.3) (ETDRS equivalent Snellen fraction: 20/50) in the bevacizumab arm and 54.8 (12.6) (20/80) in the MLT arm (p = .005). They also noted that the bevacizumab arm gained a median of 9 ETDRS letters vs 2.5 letters for MLT (p = .005), with a mean gain of 8.6 letters for bevacizumab vs a mean loss of 0.5 letters for MLT. A total of 49% of patients gained 10 or more letters (p = .001) and 32% gained at least 15 letters (p = .004) for bevacizumab vs 7% and 4% for MLT. Percentage who lost fewer than 15 letters in the MLT arm was 86% vs 100% for bevacizumab (p = .03). Mean reduction in central macular thickness was 146 µm in the bevacizumab arm vs 118 µm in the MLT arm. The median number of treatments over 24 months was 13 for bevacizumab and 4 for MLT.
This study provides evidence supporting longer-term use of intravitreous bevacizumab for persistent center-involving CSME.