A Prospective Randomized Trial of Intravitreal Bevacizumab or Laser Therapy in the Management of Diabetic Macular Edema (BOLT Study) 12-Month Data: Report 2

Purpose: To report the findings at 1 year of a study comparing repeated intravitreal bevacizumab (ivB) and modified Early Treatment of Diabetic Retinopathy Study (ETDRS) macular laser therapy (MLT) in patients with persistent clinically significant diabetic macular edema (CSME). Design: Prospective, randomized, masked, single-center, 2-year, 2-arm clinical trial. Participants: A total of 80 eyes of 80 patients with center-involving CSME and at least 1 prior MLT. Methods: Subjects were randomized to either ivB (6 weekly; minimum of 3 injections and maximum of 9 injections in the first 12 months) or MLT (4 monthly; minimum of 1 treatment and maximum of 4 treatments in the first 12 months). Main Outcome Measures: The primary end point was the difference in ETDRS best-corrected visual acuity (BCVA) at 12 months between the bevacizumab and laser arms. Results: The baseline mean ETDRS BCVA was 55.7 +/- 9.7 (range 34-69) in the bevacizumab group and 54.6 +/- 8.6 (range 36-68) in the laser arm. The mean ETDRS BCVA at 12 months was 61.3 +/- 10.4 (range 34-79) in the bevacizumab group and 50.0 +/- 16.6 (range 8-76) in the laser arm (P = 0.0006). Furthermore, the bevacizumab group gained a median of 8 ETDRS letters, whereas the laser group lost a median of 0.5 ETDRS letters (P = 0.0002). The odds of gaining >= 10 ETDRS letters over 12 months were 5.1 times greater in the bevacizumab group than in the laser group (adjusted odds ratio, 5.1; 95% confidence interval, 1.3-19.7; P = 0.019). At 12 months, central macular thickness decreased from 507 +/- 145 mu m (range 281-900 mu m) at baseline to 378 +/- 134 mu m (range 167-699 mu m) (P<0.001) in the ivB group, whereas it decreased to a lesser extent in the laser group, from 481 +/- 121 mu m (range 279-844 mu m) to 413 +/- 135 mu m (range 170-708 mu m) (P = 0.02). The median number of injections was 9 (interquartile range [IQR] 8-9) in the ivB group, and the median number of laser treatments was 3 (IQR 2-4) in the MLT group. Conclusions: The study provides evidence to support the use of bevacizumab in patients with center-involving CSME without advanced macular ischemia.