Researchers at Johns Hopkins and Genentech have found that a drug called ranibizumab is better for treating diabetic eye disease than the currently used laser surgery.
The multi-center READ-2 (Ranibizumab for Edema of the mAcula in Diabetes) clinical trial was started in December 2006, and was designed to test the long-term safety and effectiveness of injections of the drug ranibizumab in patients with diabetic macular edema, a condition characterized by swelling of the central portion of the retina, or macula, at the back of the eye.
Macular edema is one of the most common causes of blindness and occurs when fluid and protein deposits collect on or under the macula, causing it to thicken and swell.
Also, the trial, which involved 126 diabetic patients aimed at determining the comparative efficacy of ranibizumab versus conventional treatment - laser photocoagulation therapy - or both together. All the participants in the study had Diabetic Macular Edema prior to enrolment, with the majority having 20/80 vision in the eye that was treated.
In the study, patients were randomly assigned to receive one of three interventions: ranibizumab, laser photocoagulation, or a combination of the two treatments. At each visit in the six-month treatment period, patients were evaluated for vision, retinal thickening, and general eye health.
It was found that patients treated with ranibizumab experienced significantly greater improvements in visual acuity, or clarity of vision, compared with patients receiving either of the other interventions. On average, the vision of ranibizumab-treated patients improved to 20/63 at month six, as against with essentially unchanged acuity scores of about 20/80 in both the laser and the combination treatment groups.
Besides, patients treated with ranibizumab had a 56 percent reduction in excess retinal thickness, in comparison to only an 11 percent reduction in those receiving laser treatments.
"These are very encouraging results, showing that drugs we have been testing in human clinical trials can be effective in slowing or stopping the effects of eye disease brought on by diabetes," said Barbara Araneo, Ph.D., director of the complications program at JDRF.
The findings were presented at the 2008 Annual Meeting of The Association for Research in Vision and Ophthalmology, in Fort Lauderdale, Florida.