SAN FRANCISCO — Federal regulators Thursday approved what would be the first transplant of fetal stem cells into human brains.
The transplant recipients will be children who suffer from a rare, fatal genetic disorder.
The Food and Drug Administration said that doctors at Stanford University Medical Center could begin the testing on six children afflicted with Batten disease, a degenerative malady that renders its young victims blind, speechless and paralyzed before it kills them.
An internal Stanford review board must still approve the test, a process that could take weeks.
The stem cells to be transplanted in the brain aren't human embryonic stem cells, which are derived from days-old embryos. Instead, the cells are immature neural cells that are destined to turn into the mature cells that make up a fully formed brain.
Parkinson's disease patients and stroke victims have received transplants of fully formed brain cells before, but the malleable brain cells that would be used in this test have never been implanted.
Batten disease is caused by a defective gene that fails to create an enzyme needed in the brain to help dispose of brain cellular waste. The waste piles up and kills healthy cells until the patient dies. Most victims die before they reach their teens.
The idea is to inject the sick children with healthy, immature neural stem cells that will "engraft" in the brain, which will direct them to turn into cells able to produce the missing enzyme.
StemCells Inc., the Palo Alto biotechnology company developing the treatment, said it received its fetal tissue from a nonprofit California foundation that also collects tissue from miscarriages and other surgical processes.
Stanford University service chief of pediatric neurosurgery Dr. Stephen Huhn will bore small holes through each child's skull and inject the neural cells into the patients' brains. The children will be given drugs to ensure that their immune systems don't attack the new cells.