A study suggests the drug ranibizumab is associated with reducing the magnitude of legal blindness and visual impairment caused by age-related macular degeneration.
“Before ranibizumab became available in 2006, neovascular age-related macular degeneration (AMD) was reported to be the leading cause of blindness in individuals 50 years and older in the United States and throughout many parts of the world,” the authors say.
To estimate the number of individuals who may benefit from treatment with ranibizumab to treat neovascular AMD and prevent AMD-related blindness, Neil M. Bressler, MD, of the Wilmer Eye Institute at The Johns Hopkins University, and colleagues designed a study using outcomes from three previous phase 3 ranibizumab trials.
Using statistics from the Beaver Dam Eye Study and data from the 2008 U.S. Census Bureau, the model predicted that 151,340 non-Hispanic white individuals in 2008 would develop neovascular AMD. Data from the study (a phase 3 ranibizumab trial) showed an estimated one-third of these cases (51,000 individuals) would have pre-existing choroidal neovascularization (new blood vessels form in the choroid, a thin vascular layer that supplies blood to the retina) in the opposite eye.
Ranibizumab would be accessible to 103,582 individuals, researchers estimated. Based on the model designed for the study, if no treatment were given to the 103,582 cases for which monthly ranibizumab was indicated, 16,268 would progress to legal blindness in two years.
The authors estimated that monthly ranibizumab usage would reduce the incidence of legal blindness in two years by 72% to 4,484 individuals. Based on the model designed for the study, if no treatment were applied to the 103,582 cases for which monthly ranibizumab is indicated and accessible, 34,702 would progress in two years to visual impairment. The authors estimated that monthly ranibizumab usage would reduce the incidence of visual impairment in two years by 37%, to 21,919 individuals.
The authors conclude that ranibizumab would have an effect on reducing the occurrence of visual blindness in individuals with AMD when treatment is administered on a monthly basis.
The study was published in the journal, Archives of Ophthalmology.
Release Date: June 13, 2011
Source: Wilmer Eye Institute at The Johns Hopkins University
Filed Under: Drug Discovery