“This finding will be reassuring to physicians charged with delivery of this relatively new treatment,” conclude the authors of the report in the Archives of Ophthalmology online April 9.
The study involved 80 patients with clinically significant center-involving macular edema who were randomized to treatment with bevacizumab or macular laser therapy. The primary outcome was the difference in ETDRS (Early Treatment Diabetic Retinopathy Study) best-corrected visual acuity (BCVA).
Dr. Philip G. Hykin at Moorfields and colleagues report that at 24 months the mean ETDRS BCVA was 64.4 with bevacizumab versus 54.8 with laser treatment (p=0.005). Respective Snellen equivalents in the two arms were 20/50 versus 20/80.
Compared to baseline, at 2 years the bevacizumab group gained a median of 9 ETDRS letters compared with a gain of 2.5 letters with macular laser therapy, the authors report.
Other measures also favored bevacizumab therapy. For example, at 24 months 49% of patients treated with bevacizumab gained 10 or more letters compared with 7% of those treated by laser. The mean reduction from baseline in central macular thickness was 146 microns versus 118 microns in the two arms, respectively.
While the patients in the bevacizumab group received a median of 9 intravitreal injections in the first year, they needed just four in year 2, according to the report. In the other arm, a median of three laser treatments were given in year 1 and one in year 2.
“In conclusion,” Dr. Hykin and colleagues write, “this investigator-initiated single-center study provides evidence for the longer-term use of bevacizumab in the treatment of persistent DME (diabetic macular edema). Visual acuity benefit was maintained through two years with a reduced injection frequency in the second year despite the long duration of DME and multiple MLTs (macular laser treatments) before entering the study.”