Update on Stem Cell Trials for Spinal Cord Injury

In our spring newsletter, we reported on the results of the trial being carried out by the company “Asterias”, in which people who have suffered spinal cord injuries are receiving surgical injections of oligodendrocyteprecursor cells (OPCs) derived from human embryonic stem cells (hECSs) into their spinal cords. The OPC trial was based on research carried out by Hans Keirstead at the RIRC, and the current trial is called the “ST-OPCI SCiStar study”. On November 14, Asterias announced that enrollment in the trial had been accelerated with three patients having received cell injections in early November. In addition to the patient cohorts that previously received doses of 2 million and 10 million cells, two patients have now received the maximum dose of 20 million cells, which is thought to be roughly comparable to what the rats received in the initial study.

The two patients who received the 20 million cell dose are cervical AIS-A, meaning complete loss of motor and sensory function below the cervical injury site. AIS-8 patients have similar cervical injuries and complete motor loss but retain some sensory function, and Asterias believes AIS-8 patients may be particularly responsive to AST-OPCI due to the larger amount of intact spinal tissue remaining at the injury site. The company plans to report 6 month efficacy and safety data in January 2017. The “ST-OPCI SCiStar study” is an FDA approved trial that has been extensively reviewed by scientific and medical experts. The data from the trial will be fully analyzed and reported. The carefully controlled and FDA approved clinical trial that Asterias is running is in stark contrast to literally hundreds of “Stem Cell Clinics” that are popping up all over the United States that deliver untested “stem cell” products to those who are able to pay. In September, the FDA held a 2-day public meeting on possible changes in rules for stem cell clinics in the United States. Surprisingly, there are few rules and little oversight of such clinics, raising concerns that clients may be getting noncompliant cell-based interventions.

Tighter regulations may not sound like a good thing, and some people came to the meeting to testify that they had benefitted from treatments they had received from stem cell clinics. On the other hand, FDA regulations are an important reason why we can trust that the medications and treatments that we receive (and pay for) have been tested for safety and effectiveness. Patient safety IS at stake, and very few of us can afford to pay tens of thousands of dollars for something that doesn't work. The problem is that in an un-regulated market, it's not possible for most consumers to distinguish between treatments that have been tested and shown to be safe and effective vs. treatments that have never actually been tested at all. As Dr. Larry Goldstein wrote in an e-mail: “Thoughtful FDA regulation of the growing stem cell industry is essential to help consumers distinguish fraudulent claims from legitimate clinical trials, research and therapy development”.

The other huge problem is that the term “stem cell” is now being used for a number of different cell types and treatments. Clinic websites advertise different products, but there's no oversight or independent validation of claims that a particular product is actually what the clinic says it is. There's no playbook that consumers can use to figure it all out.

And there are more examples of some really ugly consequences. In July, the highly respected New England Journal of Medicine published a scientific report on a man who developed a tumor in his spinal cord after receiving infusions of different types of stem cells and a transplant of “fetal neural stem cells” into his spinal cord. Berkowitz et al., 2016, Glioproliferative lesion of the spinal cord as a complication of “Stem-Cell Tourism” (http://www.nejm.or g/doi/fu ll/ I 0.1056/NE!Mc 1600188). The patient developed pain that got worse over time and increasing paraplegia. A biopsy of the tumor revealed a mass comprised of cells from another human being that were proliferative (meaning that the tumor was growing). This article concludes: “The unregulated commercial stem-cell industry is not only potentially harmful to individual patients but also undermines attempts to study stem-cell therapies in clinical trials. This case provides further support for the conclusions of an article advocating increased investigation of commercial stem-cell clinics and increased patient education regarding the risks of stem-cell tourism. Such experimental treatments must be studied in a safe, regulated environment.” So, as we've cautioned before, y'all be careful out there!