Ranibizumab may become reasonable treatment alternative for patients with proliferative diabetic retinopathy

Among patients with proliferative diabetic retinopathy, treatment with an injection in the eye of the drug ranibizumab resulted in visual acuity that was not worse than panretinal photocoagulation at 2 years, according to a study appearing in JAMA. This study is being released to coincide with its presentation at the American Academy of Ophthalmology annual meeting.
Proliferative diabetic retinopathy (PDR; a more advanced form of the disease) is a leading cause of vision loss in patients with diabetes mellitus, resulting in 12,000 to 24,000 new cases of blindness each year in the United States. Panretinal photocoagulation (PRP; procedure that involves use of a laser) is the standard treatment for reducing severe visual loss from PDR. However, PRP can cause permanent peripheral visual field loss and decreased night vision and may exacerbate diabetic macular edema (DME; swelling of the retina in diabetes mellitus due to leaking of fluid from blood vessels within the macula), which makes alternative treatments desirable, according to background information in the article.
When used as treatment of DME, intravitreous (in the vitreous, the fluid behind the lens in the eye) anti-vascular endothelial growth factor (VEGF) agents reduce the risk of diabetic retinopathy worsening and increase the chance of improvement, making these agents a potentially viable PDR treatment. Adam R. Glassman, M.S., of Jaeb Center for Health Research, Tampa, Fla., and the Writing Committee for the Diabetic Retinopathy Clinical Research Network, and colleagues conducted a study that included 305 adults with PDR; both eyes were enrolled for 89 participants (1 eye to each study group), with a total of 394 study eyes. Individual eyes were randomly assigned to receive PRP treatment, completed in 1 to 3 visits (n = 203 eyes), or the anti-VEGF agent ranibizumab, by intravitreous injection at study entry and as frequently as every 4 weeks based on a structured retreatment protocol (n = 191 eyes). Eyes in both treatment groups could receive ranibizumab for DME. The trial was conducted at 55 U.S. sites.
The researchers found that intravitreous ranibizumab met a prespecified noninferiority (not worse than) outcome of visual acuity change at 2 years than in the PRP group. There was no statistically significant visual acuity difference between the groups at 2 years, with the authors noting that 53 percent of the PRP group received ranibizumab injections for DME.
“Although longer-term follow-up is needed, ranibizumab may be a reasonable treatment alternative at least through 2 years for patients with PDR,” the authors write.