Transplants of a fetal neural stem cell product seem safe, according to a 12-month study on six children with a horrible neurodegenerative disease called neuronal ceroid lipofuscinosis or Batten disease. Furthermore, the company reported results from an autopsy of a treated patient who died from the disease. (See Girl dies in stem cell trial for Batten disease ). These indicate that the injected cells engraft and survive in the brain for close to a year.
Whether cells can survive after transplant is considered a crucial requirement for whether many cell therapies can work at all, and StemCells Inc, the company sponsoring the trial, explicitly thanked the child’s parents for allowing the autopsy to be performed.
Batten disease is a progressive neural degenerative disease in which brain cells poison themselves because they lack a crucial enzyme that clears away unnecessary fats and proteins. The hope is that transplanted cells can make enough of the enzyme to stall toxic build-up in the host cells as well.
As is typical in clinical trials, the small study, which lacked a control group, was not designed to assess whether the experimental procedure could help patients, only whether or not it would harm them. A summary of data and results can be found in this press release. Each patient received injections to 8 spots in the brain totaling approximately 500 million or a billion cells. Adverse events were reported, but none could be attributed to the stem cell injections.
StemCells Inc received permission in December launch a similar trial for Pelizaeus-Merzbacher Disease (PMD), also a fatal brain disorder that affects mainly young children.
Other companies that have received or applied for approval using fetal stem cell based products for neurodegenerative disease include ReNeuron (which received permission from the UK MHRA to test cells for stroke in January) and NeuralStem (its trial for Lou Gehrig’s disease was put on hold by the US FDA in February).
NeuralStem and StemCells Inc have been conducting a very heated exchange and lawsuit about who holds the rights to use neural stem cells therapeutically. See warring press releases from NeuralStem and Stem Cells Inc from this May.
As an aside, StemCells Inc has also sent a letter to the Children’s Hospital of Orange County, warning that its intellectual property rights might lay claim to a neural stem cell bank that CHOC has been building up and developing for years. CHOC responded by ceasing to distribute the lines. This has been reported here. I’ve spoken to players involved, and basically the people with the power to put cooperative agreements together don’t have much incentive to do so. StemCells is trying to bring a product to market. CHOC is focused on treating patients and avoiding lawsuits. Making a resource available for basic and translational research isn’t high on the to-do list of executives at either entity. (Last I checked, they were in the process of setting up a meeting and reviewing terms.)
For some examples of what it takes to turn a stem-cell product into a treatment for neural diseases, see our article Stem cells and neurodegenerative disease: cool science and skepticism