printable versionFDA approves brain stem cell transplant trial
BY KRISTA CONGER
For the first time, the Food and Drug Administration has approved a clinical trial to test whether a purified population of human neural, or brain, stem cells can be safely used in humans. The medical center is one site being considered for the trial, which is designed to investigate the effect of transplanted stem cells in children with Batten disease—a fatal genetic disorder.
The FDA-approved protocol, which was designed in part by Stanford physicians and researchers Stephen Huhn, MD, and Greg Enns, MD, will now be submitted to the medical center's Institutional Review Board for the consideration afforded all trials involving human subjects. Huhn and Enns are slated to co-direct the trial if the IRB approves the protocol.
Researchers speculate that the cells, which are isolated from fetal brain tissue, may provide enzymes that are missing or defective in patients with the condition. However, the planned phase-I trial is primarily designed to test the safety of the treatment.
"The most important thing as we embark on any new treatment, after completion of the animal studies, is to show that the proposed therapy causes no harm," said Huhn, an associate professor of neurosurgery and pediatrics. "The first issue is to show safety. We'll make sure the parents understand this is the beginning of a very long process."
Huhn and Enns, an assistant professor of pediatrics, have worked for several years with the Palo Alto company StemCells Inc. to conduct preliminary tests in animals and to design the human trials.
About two to four of every 100,000 children born in this country have Batten disease, which is caused by an abnormal accumulation of complex molecules in the brain. Clinical symptoms include blindness, seizures and dementia. The disease is fatal, usually by late childhood or early adulthood.
The proposed study would enroll six severely affected children up to age 12. They would be separated into two groups of three to test two different "doses" of the cells, which would be transplanted into key locations in the brain.
Previous studies in mice have indicated that these human neural stem cells can migrate to different areas of the brain and integrate into the surrounding tissue. Studies by StemCells Inc. have also shown in a direct animal model of the human Batten disease that the cells make the defective enzymes and that production of one enzyme increases post-transplantation.
Huhn and Enns have been paid consultants to StemCells Inc., but have no equity in the firm. Their paid consultancy will be terminated when the study is officially submitted for IRB approval.