Geron implants embryonic stem cell-derived oligodendrocyte progenitor cells into their first spinal cord-injured patient


On October 11, 2010, Geron Corporation announced that they had announced the enrollment of the first person in the company’s Phase I clinical trial of their human embryonic stem cell (hESC)-derived oligodendrocyte progenitor cell, GRNOPC1 for treating spinal cord injuries. Because this is a Phase I study, its primary objective is to determine the safety and tolerability of this cell line in patients with complete American Spinal Injury Association (ASIA) Impairment Scale grade A thoracic spinal cord injuries. According the Geron Corporation, patients in the study must be newly injured and receive GRNOPC1 within 14 days of the injury.
Geron enrolled their first patient at the Shepherd Center, which is a 132-bed spinal cord and brain injury rehabilitation hospital and clinical research center in Atlanta, GA. This is not the only center that can enroll patients in this clinical trial.
Geron President’s and Chief Executive Officer, Thomas B. Okarma, Ph.D., M.D., said this of his company’s clinical trial: “Initiating the GRNOPC1 clinical trial is a milestone for the field of human embryonic stem cell-based therapies… When we started working with hESCs in 1999, many predicted that it would be a number of decades before a cell therapy would be approved for human clinical trials. This accomplishment results from extensive research and development and a succession of inventive steps to enable production of cGMP master cell banks, scalable manufacture of differentiated cell product, and preclinical studies in vitro and in animal models of spinal cord injury, leading to concurrence by the FDA to initiate the clinical trial.”
The President of the Shepherd Center, Donald Peck Leslie, M.D., said that “We are pleased to have our patients participating in this exciting research. . . Our medical staff will evaluate the patients’ progress as part of this study. We look forward to participating in clinical trials that may help people with spinal cord injury.”
The disappointing aspect of the media coverage of this event is the huge excitement over the “what might be” potential of embryonic stem cell- (ESC) derived treatments for spinal cord injuries even though real treatments are alive and well that use non-ESC resources. Even in patients fifteen years after their spinal cord injury have been helped by somatic stem cell treatments. Laura Dominguez is one such patient. She can now walk with braces even though her spinal cord injury rendered her completely unable to walk.
The second issue is the fact that there is a real risk of tumor formation. To be fair, these differentiated derivatives of ESCs do not consistently cause tumors in laboratory animals, but there is no guarantee that their tumor-causing capacity has been completely abolished. Hans Keirstead at UC Irvine, who did the groundwork on the ESC-derived cell line, did not see tumor formation when he transplanted these cells into rats. Geron scientists have also not reported tumor formation in their experiments. However, tumor formation is still a concern, and the fact that Geron has pledged to observe these patients for 15 years after the procedure testifies to this risk.
Finally, work by Geron scientists have established that these ESC-derived cells do not work if they are implanted one-two weeks after the injury. Why are we putting so much money into something that has such distinct limitations?
The largest concern is the fact that these ESC-derived cells are made by destroying human embryos. We were all embryos at one time. If I were to show you a picture of myself at the eight-cell stage, you would have made the connection between me as an embryo and me as an adult. The only difference is that the embryo is smaller, less mature, located in my mother’s uterus, and more dependent than I am now. None of these differences are essential differences between who I am now and who I was then. We do not exile people from humanity because they are too small, too dependent on someone else, located in a place we do not like, or who are immature. These are accidental differences and not essential differences. To destroy these embryos at this young stage is to kill a very young human being simply because we can. It is a simple case of the strong exerting their will over the weak in a way that ends the life of the weak. It is simple murder. This is too great a price to pay for cures. We can do better.