Roche's Dry AMD Therapy Shows Positive Results in Early Human Study
An emerging therapy to slow the progression of geographic atrophy (GA), the advanced form of dry age-related macular degeneration (AMD), has performed encouragingly in an 18-month, Phase II clinical trial involving 143 participants. The results provide some optimism for preserving vision from a leading cause of blindness in people over 50 in developed countries.
“These early results are good news for people with geographic atrophy, a blinding form of AMD for which there are no FDA-approved therapies,” says Brian Mansfield, Ph.D., deputy chief research officer, Foundation Fighting Blindness. “However, a larger, Phase III trial will give us a better idea of the therapy’s true potential for saving vision. We need to be cautious about expectations until we get more data.”
Known as lampalizumab, the treatment showed a 20.4 percent reduction in the growth rate of GA lesions, which are caused by accumulation of waste deposits and the subsequent degeneration of retinal pigment epithelial (RPE) cells underneath the macula, or central retina. The loss of RPE cells leads to loss of photoreceptors, the cells that provide vision. In the Phase II clinical trial, lampalizumab was administered monthly or every other month through an injection into the vitreous, the jelly-like substance in the interior of the eye.
Roche, the pharmaceutical company developing the drug, reported that the progression rate of GA in a subpopulation of study participants with certain exploratory biomarkers, or disease characteristics, decreased by 44 percent. For participants with the exploratory biomarkers and better vision (20/50 to 20/100), the rate of progression was reduced by 54 percent. Roche has not disclosed which biomarkers were used in the study. They could be any number of characteristics, including genetic factors, proteins and the size of the GA lesions.
While there are currently no therapies approved by the U.S. Food and Drug Administration (FDA) for GA, the AREDS supplement, a combination of vitamins and nutrients available over the counter, reduced the risk of GA and wet AMD by 25 percent in a large-scale clinical trial.
Three therapies — Lucentis®, Avastin® and Eylea® — are frequently prescribed for people with wet AMD, which is characterized by the growth of vision-robbing blood vessels underneath the retina. Lucentis and Eylea are FDA-approved for the treatment of wet AMD. Avastin is FDA-approved for cancer, but used frequently off-label as a wet AMD therapy.
Lampalizumab is a protein designed to inhibit a part of the immune system’s defense against infection. A number of research studies, including genetic investigations funded by the Foundation, have associated over activity of the immune system with the development of AMD.