For the first time, researchers are using embryonic stem cells in a clinical trial to treat patients with spinal cord injuries. The trial strives to test whether these cells can be safely used to treat humans.
This initial investigation of embryonic stem cells stands apart from prior trials, which have all relied on adult stem cells. If successful, it may be expanded to larger clinical trials.
Geron Corporation, a Menlo Park-based company that develops cellular technology, sponsored the trial. Overall, the trial may enroll up to 10 patients with spinal cord injuries in seven locations across the country.
The Stanford School of Medicine and Santa Clara Valley Medical Center, collaborating together, constitute the third clinical site for the trial. Cells will be grown at Stanford, while surgeries will be administered at the Valley Medical Center.
At Stanford, Gary Steinberg, professor of neurosurgery, and Marco Lee, clinical assistant professor of neurosurgery, have been authorized to implement the new treatment.
“We are very excited about this trial,” Lee said. “This trial marks the first FDA-approved, clinical, phase-one embryonic stem cell trial. If this initial clinical trial proves to be safe, the FDA will approve further trials with a larger patient pool.”
“Most of the people involved would be overjoyed if there is no adverse reaction,” Steinberg said.
Adding to the excitement is the fact that Stanford and Santa Clara are two of a limited number of institutions that will have the opportunity to carry out this research.
“Stanford is the only site west of the Mississippi,” Steinberg said. “Geron was very selective who got invited to participate.”
Northwestern University is the only other site that has been officially identified by Geron. The company has yet to disclose information on the five remaining sites.
The company wanted facilities that could rigorously carry out the clinical trial and provide the necessary medical support for participating patients. The medical centers need to be equipped to take care of patients with spinal cord injuries.
The clinical trial recruits patients who recently suffered a trauma or blunt injury to the thoracic region of the spinal cord, which stretches from the top of the shoulder blades to the bottom of rib cage. The patients qualify as paraplegic because they have lost motor abilities from the waist down, including bowel control. The participants have usually been in car accidents and have experienced a crushing fracture to the spine.
Individuals with penetrating wounds, such as bullet or knife wounds, are not qualified to enroll in the study. Researchers have been able to use embryonic stem cells to repair blunt spinal injuries in animal models, but not penetrating spinal injuries.
To participate in the trial, a patient must notify his doctors and request to opt-in within seven to 14 days of his injury.
“This requires patients to come to terms with their condition and request for the new procedure,” Lee said. Finding suitable participants for the trial can be difficult, because many patients fully cannot come to terms with their situation within two weeks of their traumatic accidents.
Since the clinical trial is currently in its preliminary stages, there are still no conclusive results. Researchers do not know if there will be adverse reactions, such as tumor formation, from the injection of stem cells into the spinal cord. Positive animal model results are not easily transferable to humans.
But scientists remain hopeful.
“There is a lot of excitement about this, but there is a lot of caution,” Steinberg said. “Advances in medicine are made in small steps, not quantum leaps. That being said, we’ve never had something like this before.”