Findings set stage for first clinical trial of stem cell-based therapeutic approach for AMD.
Using a novel patient-specific stem cell-based therapy, researchers at the National Eye Institute (NEI) prevented blindness in animal models of geographic atrophy, the advanced “dry” form of age-related macular degeneration (AMD). The protocols established by the animal study* set the stage for a first-in-human clinical trial testing the therapy in people with geographic atrophy, for which there is currently no treatment.
“If the clinical trial moves forward, it would be the first ever to test a stem cell-based therapy derived from induced pluripotent stem cells (iPSC) for treating a disease,” said lead investigator Kapil Bharti, Ph.D.
The therapy involves taking a patient’s blood cells and, in a lab, converting them into iPS cells, which can become any type of cell in the body. The iPS cells are programmed to become retinal pigment epithelial (RPE) cells, which nurture photoreceptors, the light-sensing cells in the retina. In geographic atrophy, once RPE cells die, photoreceptors eventually also die, resulting in blindness. The therapy is an attempt to shore up the health of remaining photoreceptors by replacing dying RPE with iPSC-derived RPE.
Before they are transplanted, the iPSC-derived RPE are grown in tiny sheets one cell thick, replicating their natural structure within the eye. This monolayer of iPSC-derived RPE is grown on a biodegradable scaffold inserted between the RPE and the photoreceptors. The investigators report that the transplanted cells functioned properly and safely.
The planning of a Phase I clinical trial testing the safety of the therapy in humans is underway and will be initiated after U.S. Food and Drug Administration approval.
*Sharma R, et al, “Patient-specific clinical-grade iPS cell-derived retinal pigment epithelium patch rescues retinal degeneration in rodent and pig eyes.” January 16, 2019 Science Translational Medicine.