(dailyRx News) Patients with a persistent form of diabetic macular edema, which causes swelling of the retina, appear to do better with a prescribed drug over laser therapy, the long-preferred treatment for the eye condition.
Researchers found that Avastin (bevacizumab) may be more effective at treating the retina swelling than the surgical option, which lowers the risk of moderate vision loss but improves visual acuity in less than 3 percent of patients.
Ranjan Rajendram, MD, FRC Ophth., of Moorfields Eye Hospital in London, found that the drug maintained its effectiveness 24 months later in patients with significant forms of the condition. It had previously been found to be effective for 12 months.
Researchers have been looking for another treatment because few patients experience improved visual acuity following the surgical option, also known as macular laser therapy (MLT).
During the randomized controlled BOLT trial of 80 patients with significant diabetic macular edema, investigators evaluated the effectiveness of injections of bevacizumab into the eye as compared to the surgical procedure. The patients were followed for two years.
After two years, the average best-corrected visual acuity was 64.4 (equivalent to 20/50 vision) among the group that took the drug as compared to 54.8 (equivalent to 20/80 vision) in the surgical group, an average gain of 8.6 letters in an eye exam for bevacizumab and average loss of 0.5 letters for MLT.
At 24 months the group taking the drug gained an average of nine letters versus 2.4 letters in the surgical group as compared to the study's beginning. Also at the 24-month mark, nearly half of the bevacizumab group gained 10 or more letters and 32 percent gained at least 15 letters, as compared to 7 percent and 4 percent, respectively, in the group that received surgery.
Investigators said the findings should reassure doctors treating patients with persistent diabetic macular edema using the newer drug.
Dr. Chris Quinn, an optometrist with Omni Eye Associates, noted that doctors have not come to expect an improvement with laser surgery, but rather use it to slow or prevent further vision decline.
"Although more study is needed, this study supports an increasing role of bevacizumab as either a primary or adjunctive treatment for patients with DME. It should be noted however, that although intra-vitreal injections are generally safe when performed properly, it is a more invasive treatment when compared to laser treatments and the risk of complications associated with intra-vitreal injections is greater than laser," he said.
The study was recently published in the Archives of Ophthalmology, a Journal of the American Medical Association Network publication.