Jan. 23, 2009 — -- The Food and Drug Administration approved the first clinical trial today that will use human embryonic stem cells to potentially draw recent paraplegics out of the wheelchair and back on their feet.
Scientists hope the stem cell therapy will prevent permanent paralysis caused by acute spinal cord injuries and even return feeling and movement in patients who suffered the paralyzing injury two weeks before treatment. The treatment showed positive results when tested in rats.
"In animal models, this restores the animal's ability to walk," Dr. Tom Okarma, president and CEO of Geron Corp., the company putting on the trial, told "Good Morning America" today. "And that's what we hope to achieve in the first trial with patients with spinal cord injury."
A group of eight to 10 paraplegics who still have use of their arms but not legs will be injected with cells derived from embryonic cells, Okarma told The Associated Press.
Although the aim of the study is to test the procedure's safety, doctors will be on the lookout for much more.
"The focus of this trial is safety," Sean Morrison, director at the University of Michigan Center for Stem Cell Biology, told "GMA."
"And if Geron can show it's safe to derive stem cells into patients, that will be an important precedence to enhance future trials for all diseases that could benefit from this work from juvenile diabetes to other types of neurological disorders."
Doctors will also be on the lookout for potentially hazardous side effects. The cells could create benign tumors and there is a danger the patient's immune system could attempt to reject the injections, "thereby increasing the inflammation in the spinal cord instead of decreasing it," Morrison said.
In response, doctors plan to provide the patients with anti-rejection drugs for two months after the initial injection, the AP reported.
If successful, supporters see nearly endless potential for the treatment.
"This is vast," said Peter Kiernan, chairman of the board of directors of the Christopher and Dana Reeve Foundation. "This is like the dawn. It's not a comet across our sky; it's the beginning."
Treatment Requires Patience
Christopher Reeve, the actor who famously portrayed Superman on the big screen before a fall off a horse caused paralysis from the neck down, championed the cause of those with spinal cord injuries until he died in 2004. Kiernan said the Man of Steel would have taken hope in the news.
"You know Chris was an impatient man," he said. "He would say 'Why have we waited so long? Let's get to work.' Today, the hard work starts."
Even if the treatment is successful, Okarma warned that patients might have to show a little more patience.
They will not "get up and dance the next day," he told the AP, but the movement the treatment hopes to provide could be improved with physical therapy.
Michigan's Morrison said that almost any amount of movement would be a tremendous breakthrough.
"It may not be realistic to hope that this kind of therapy will allow patients with severe injuries to walk again," he said. "Even if you would restore lateral function in a subset of patients, that would be a real important advance and the trial would be a huge success."
Though the approval for the trial is new, the ferocious ethical debate surrounding the use of stem cell therapy is anything but.
In order to use the multifunctional stem cells, the embryos have to be destroyed, an act some critics have likened to murder.
Geron is using discarded embryos from in-vitro fertilization procedures that were destined to be destroyed but that has not derailed some critics.
"The current lines of human embryonic stem cells are derived from living human embryos," David Prentice of the Family Research Council told "GMA."
"There is a concern that you're cannibalizing human lives for potential treatments."
Former President George W. Bush banned federally supported embryonic stem cell research during his administration.
Newly inaugurated President Obama has said he would relax such restrictions but the FDA's decision was not influenced by political timing, Okarma told the AP.
More Diverse Treatments
The slightly less controversial use of adult stem cells has been tested in humans but embryonic cells have better potential for more diverse treatments, Kiernan said.
"When you're dealing with a problem as vexing as spinal cord injury, you don't want to enter the arena with one hand tied behind your back," he said. "This liberates the scientists to go where science can take them. It takes the politics out of science and enables them to do their job."
For Kiernan, the FDA's approval marks a significant shift that's been years in the making.
"I think the parade has started and the FDA took its rightful place at the head of the parade," he said. "We've gone through eight years of fighting to get this kind of approval. That's why we're so elated to be on our way. That's the exciting part."