First Patient Treated With Embryonic Stem Cells
Paralyzed Atlanta Patient Gets Stem Cells Injected Into Spine
Oct. 11, 2010 - The first person treated with embryonic stem cells is an Atlanta patient paralyzed by a recent spine injury.
The Geron Corp. GRNOPC1 stem cells come from embryos left over after in vitro fertilization and donated by the parents. The FDA approved the study in early 2009.
The clinical trial is a first step toward an eventual cure for paralysis, says study leader Richard Fessler, MD, PhD, professor of neurological surgery at Northwestern University Feinberg School of Medicine and a surgeon at Northwestern Memorial Hospital.
"We would love to see paralysis cured. Will that happen with this study? Of course not. We would be thrilled to see any beneficial effect at all," Fessler tells WebMD. "This is merely the first step in a long process that will take 10-25 years."
The study, taking place at up to seven medical centers, will enroll 10 patients in its first stage. Patients with complete grade A thoracic spinal cord injuries will be treated seven to 14 days after their injury. Such patients cannot move or feel their lower bodies and usually lose bladder and bowel control. Physical therapy has only limited benefits.
Embryonic Stem Cells Mature Before Injection
Before being given to patients, the embryonic cells are matured into "precursor cells" destined to become oligodendrocytes. These are the cells that make up the myelin sheaths that protect nerves in the spinal cord.
It's hoped that the GRNOPC1 cells will restore spinal function by replacing lost myelin and by giving off chemical signals that promote new nerve growth.
The cells are injected directly into the site of the spinal injury using a syringe positioning device that attaches to the frame of the operating room table.
Patients in the study must undergo short-term immune-suppressing therapy to ensure that their bodies do not reject the new cells.
The Atlanta patient, and nine more patients to be enrolled in the first phase of the clinical trial, get only small doses of the GRNOPC1 cells. It's the human equivalent of the smallest dose to show benefit in animal studies. If the treatment proves safe, the next phase of the study will use up to tenfold larger doses of the cells.
Key questions are whether the stem cells will spur growth of tumors called teratomas, whether the cells will be rejected by the immune system, and whether there will be unintended consequences such as nerve pain.
In preclinical studies, animals with severe spinal injuries regained the ability to walk after treatment with OPC1 cells. The animals did not develop teratomas, reject the cells, or suffer nerve pain.
In addition to showing clinical improvement, treated animals' damaged nerves became coated with new myelin and there was new nerve growth in the vicinity of the injected cells.