For years, scientists have held out the promise that embryonic stem cells could repair damaged spinal cords and cure other serious ailments.
Scientists today got one step closer to making that promise a reality as they began an embryonic stem-cell treatment on a patient with spinal cord injuries. It is the first time a medical therapy has been used on a human in a government approved study.
"This is the dawn of a new era in medical therapeutics. We are leaving behind the days of using pills to treat symptoms, and entering a new era where we're using living human cells to permanently restore organ function damaged by a disease or an injury," said Tom O'Karma, president and CEO of Geron Corporation, the company conducting the trial.
It's a cautious start. Scientists from Geron injected the first human subject Friday at the Sheperd Center, a 132-bed spinal cord and brain injury rehabilitation hospital and clinical research center in Atlanta -- one of seven potential sites in the country that can enroll patients in the new clinical trial for the therapy. The company says it will add eight to 10 additional patients to the other national sites in the next year.
The company won Food and Drug Administration approval after showing promising results in lab rats. Rodents with little use of their back legs and tails were able to walk again within weeks; the embryonic stem cells helped repair their damaged nervous system.
For now the company is playing down expectations in the human trial.
"We can only admit one patient a month for the first few patients, so it will take about six months to a year before we have enough rigorous data to be able to say something about safety and any possible efficacy that we detect," O'Karma said.
If the stem cell therapy, which in this case is for the treatment of spinal cord injuries, is deemed safe, it will be seen as a milestone. Improvement of the patients in this trial would be viewed as an astounding success.
However, if the treatment fails -- or worse, if patients die -- doctors said it will be a devastating setback for the use of embryonic stem cells.
"This is a huge milestone for the field, marking the first time a product of a human [embryonic stem cell] has been transplanted into a patient," said Dr. George Daley, director of Stem Cell Transplantation at Children's Hospital Boston and the Dana-Farber Cancer Institute in Boston. "It has taken years and reams of regulatory documentation to get to this milestone. I hope the trial proceeds safely and that this represents just the first of many trials to follow."
"This is an important milestone," said Sean Morrison, director of the Center for Stem Cell Biology at the University of Michigan in Ann Arbor. "Nonetheless, we must bear in mind that there is a real concern about safety, since these cells have not been used clinically before.
"If the cells do prove to be safe in this trial, that would represent another milestone that would make it easier to perform future trials involving cells obtained from [human embryonic stem] cells," Morrison said. "If they observe adverse events in the patients, such as tumor formation, this could really set the field back."