Researchers at the U-M Kellogg Eye Center have reported early results from a groundbreaking study testing a new stem cell treatment for dry age-related macular degeneration (AMD), the leading cause of severe vision loss and blindness in older adults. In this study, Luxa Biotechnology, the sponsor of the clinical trial, used donated adult eye tissue to collect special cells called retinal pigment epithelium (RPE) cells. These cells are important because, in dry AMD, they are lost or damaged, causing vision loss. Luxa collected stem cells from these RPE cells and in the lab, grew them and turned them back into mature RPE cells that could potentially replace the damaged cells in patients. The newly grown RPE cells were shipped from a lab in California to Michigan. There, Rajesh Rao, M.D., the Leonard G. Miller Professor of Ophthalmology and Visual Sciences, and Associate Professor in the Departments of Ophthalmology & Visual Sciences, Pathology, and Human Genetics, led the effort to surgically implant these cells under the retinas of patients with advanced dry AMD. The goal was to see if these stem cell-derived RPE cells could safely take the place of lost or diseased cells and help preserve or improve vision. “This is the first clinical trial to use adult RPE stem cells as a therapy for vision loss in dry AMD,” says Dr. Rao. “It’s a unique approach because we’re injecting these RPE cells, grown from adult stem cells, directly into the part of the eye that is most affected by this disease.” The main aim at this stage is to see if this new therapy is safe for patients and if the body can tolerate the new cells. “We are evaluating the safety and tolerability of injecting these stem cell-derived RPE cells under the retina,” he says. “Our hope is that these new cells, made from adult donor tissue, can help replace those lost to dry AMD.” So far, nine patients have received the implant at the Kellogg Eye Center, and more are being treated at partner sites in California. The plan is to treat a total of 18 patients at all sites combined. “We’re working with other top centers as part of a careful, step-by-step process for this early-stage human trial,” says Dr. Rao. The first results are promising. There have been no serious safety problems related to the surgery or the cell implant. “We did not see vision loss, tumors, or unusual inflammation in these first patients. The procedure was safe and well tolerated,” he says. Early vision results are encouraging. Some patients with very poor eyesight (20/200 to 20/800 vision) showed significant improvements with an average gain of 22 letters on an eye chart one year after surgery. Those with better vision (20/70 to 20/200) gained about four letters six months after the implant. Typically, dry AMD leads to gradual vision loss, which was seen in the untreated eyes but not in those that received the new cells. This is the first trial of its kind at the University of Michigan and in the state. “It could lead to future stem cell treatments for AMD and other retinal diseases, and puts U-M at the forefront of regenerative medicine for eye care,” says Dr. Rao. “The trial continues, with more patients receiving higher doses of the cell therapy.”

The technology behind the therapy was created by U-M-affiliated scientists Drs. Jeffrey Stern and Sally Temple, founders of the Neural Stem Cell Institute in New York, and of Luxa Biotechnology.