Ten stem cell science and spinal cord injury specialists have poked holes in the small unpublished clinical trial that was used to form the basis of the conditional approval, which question the efficacy and safety of the treatment, commenting at the request of Nature News.
Stemirac therapy involves extracting mesenchymal stem cells from an individual who suffered from a spinal cord injury to grow 50-200 million in a lab, then within 40 days of the injury intravenously infusing them back into the patient. How it works to repair damage is believed to have something to do with inflammation , and protecting existing neurons or turning into nerve cells themselves according to Professor Osamu Honma from Sapporo Medical University; this is based on an unpublished 13 patient trial which is suggested to see 12 of the 13 participants improve by 1 level on the American Spinal Injury Association Impairment Scale.
Many others remain leery as without a double blind trial design there is no way to prove improvements were not due to natural healing and physical rehabilitation after the injury says neurologist Bruce Dobkins from the University of California. He then goes on to add the trial as designed can’t reveal efficacy, and the claim of the MSCs converting to neurons in the trial is another red flag.
Another reason of concern as shown in previous research is of MSCs infused intravenously tending to get trapped in the lungs which are connected to dangerous blood clots, making it difficult to see how they would be effective in the spinal cord, according to Pamela Robey NIH stem cell researcher.
Neurosurgeon James Guest from the Miami Project to Cure Paralysis says the approval is an unfortunate step away from everything researchers have learned over 70 years about how to conduct a valid clinical trial providing burden of proof.
Standing by Honmo’s research Masanori Fukushima has emphasized some of the trial participants were too seriously injured to have had achieved natural healing. Adding he thinks the treatment is safe and is preparing to publish a paper, and he didn’t do a double blind study as Japan’s regulations don’t require it. Approximately 5,000 people a year suffer spinal cord injury in Japan, totally upwards of 100,000 patients who stand to benefit.
When Nipro Corp begins selling Stemirac it will mark long awaited activity in regenerative medicine after years of delay and disappointments. However, it’s not necessarily the entry the industry has been waiting for, which currently has moved on to exploring next-gen stem cell based therapies.
