A prescription drug commonly used to treat age-related vision loss also reverses vision loss caused by diabetes, according to a new study led by investigators from the USC Eye Institute.

Rohit Varma

“We found that ranibizumab can save the sight of thousands of working-age individuals suffering from diabetic eye disease, as standard treatments such as laser are not as effective,” said Rohit Varma, MD, MPH, director of the USC Eye Institute, professor and chair of ophthalmology at the Keck School of Medicine of USC and the study’s lead author.

Diabetic retinopathy and diabetic macular edema are the leading causes of vision loss in working-age adults in the United States, according to the National Eye Institute. Laser surgery is the standard treatment for advanced stages of the disease, which is characterized by blurred vision, but previous research has shown that only 30 percent of patients saw improvement in their vision as a result.

Varma’s team developed a population-based model that suggests that administering 0.3 milligrams of ranibizumab every four weeks to patients with diabetic macular edema would reduce the number of cases of vision impairment by 45 percent, or 5,134 individuals, and the number of cases of legal blindness by 75 percent, or 1,275 individuals.

The model was based on the approximately 37,000 Hispanic and non-Hispanic white adults with diabetic macular edema in the United States for whom ranibizumab treatment could be used. Because other race and ethnic groups were not included in the study, the treatment may benefit even more people than the study results show.

Ranibizumab is manufactured and marketed by Genentech Inc. under the trade name Lucentis. The study published Feb. 7 in the online edition of the medical journal Ophthalmology was supported in part by Genentech.

— Alison Trinidad