Blindness caused by diabetes may be reversed by eye injection, a new study revealed. The drug lucentis or ranibizumab is significantly effective as a treatment for proliferative diabetic retinopathy (PDR).
Compared to standard treatments such as panretinal photocoagulation (PRP) or laser therapy, eye injection improves sight more efficiently, experts said. Laser therapy usually causes side effects such as reduced night vision and loss of peripheral vision. It could also worsen diabetic macular edema (DME).
In a study published in the Journal of the American Medical Association, researchers from the Diabetic Retinopathy Clinical Research Network (DRCR.net) conducted a randomized clinical trial and examined the efficacy of Lucentis injections against laser therapy.
Researchers included 305 participants with 394 eyes who had PDR in the study. These participants were enrolled at 55 clinical sites all over the country. Assignment of treatment, whether laser therapy or injection of Lucentis, was done randomly.
About half of the eyes that were assigned to the laser therapy group required more than one round of treatment, while the eyes that received Lucentis had the drug injected into the eye once per month for three months until the disease stabilized.
"Patients who received Lucentis showed a little bit better central vision, much less loss of their side vision, and substantially less risk for surgery than patients who received laser treatment," explained Dr. Lloyd Paul Aiello, professor at Harvard Medical School.
Aiello, who is also the director of the Beetham Eye Institute at the Joslin Diabetes Center, said the study's findings will alter the current treatments for patients with PDR.
Lucentis is commonly used in treating DME. The patients in the laser therapy group who had this disease were allowed to be injected with Lucentis, if it was necessary. About 53 percent of the group received Lucentis injections, while 6 percent of the eyes in the Lucentis group received laser therapy for other issues aside from DME.
Diabetic retinopathy occurs when levels of blood sugar are high, damaging the cells at the back of the eye. As it worsens, the blood vessels become swollen and they lose their ability to function correctly. It becomes proliferative when the production of a protein called vascular endothelial growth factor is elevated.
In turn, the production of this protein causes the development of abnormal and new blood vessels that are prone to bleeding. When that happens, a surgical procedure called vitrectomy is needed to clear the blood. Untreated, the disease can lead to loss of eyesight.
Researchers said the disease is the top cause of blindness in patients with diabetes mellitus, with 12,000 to 24,000 new cases every year in the United States. More than 7.7 million residents in the U.S. are diagnosed with diabetic retinopathy.
The study, which was funded by the National Institutes of Health, the National Eye Institute, and the National Institute of Diabetes and Digestive and Kidney Diseases, will be presented at the annual meeting of the American Academy of Ophthalmology.