Superiority of anti VEGF alone for diabetic macular edema may not be maintained long term

In treating diabetic macular edema, the short-term superiority of bevacizumab alone over bevacizumab with triamcinolone acetonide and macular laser photocoagulation may not be sustained long term, a study showed.

Of 150 eyes initially enrolled in the randomized trial, with 50 assigned to each treatment arm, 39 that received 1.25 mg Avastin (bevacizumab, Genentech), 36 that received bevacizumab plus 2 mg triamcinolone acetonide and 38 that underwent focal or modified grid laser remained in the study at 24 months.

Re-treatment occurred at 3-month intervals in 94.9%, 75% and 81.6% of eyes, respectively. Significantly superior visual gains demonstrated in the bevacizumab group at 6 months were not sustained up to 24 months, and visual difference among the groups was not significant at all visits; however, mean improvement was greater overall in the bevacizumab group.

According to the study authors, the analysis confirmed the prior conclusion that, while laser can stabilize vision, it does not significantly improve outcomes long term. Moreover, it also supported the previous finding that triamcinolone acetonide may have no additive benefit over bevacizumab and may be associated with less favorable outcomes in patients who received combination treatment.

Notably, missing data for 24.6% of cases at final follow-up diminished the study’s power, the authors said. Also, the 12-week re-treatment interval may have resulted in some patients being undertreated.