StemCells, Inc. announced that interim six-month data from the first patient cohort in the Company's Phase I/II clinical trial of its proprietary HuCNS-SC® product candidate (purified human neural stem cells) for chronic spinal cord injury continues to demonstrate a favorable safety profile, and shows considerable gains in sensory function in two of the three patients compared to pre-transplant baselines. The third patient remains stable. The data was presented by Armin Curt, M.D., principal investigator for the clinical trial, at the 51st Annual Scientific Meeting of the International Spinal Cord Society in London, England. The trial represents the first time that neural stem cells have been transplanted as a potential therapeutic agent for spinal cord injury.
"As with the three-month assessments, these three patients have tolerated the cell transplantation very well, and we have no safety concerns at this point," said Dr. Curt, Professor and Chairman of the Spinal Cord Injury Center at Balgrist University Hospital, University of Zurich. "We are very intrigued to see that two of the three patients have gained considerable sensory function. The gains in sensation have evolved in a progressive pattern below the level of injury and are unanticipated in spinal cord injury patients with this severity of injury, suggesting that the neural stem cells are having a beneficial clinical effect. Sensory function of all these patients was stable before transplantation, so the reappearance of sensation is rather unexpected."
Stephen Huhn, M.D., FACS, FAAP, Vice President and Head of the CNS Program at StemCells, added, "To see this kind of change in patients who truly have the worst-of-the-worst type of injury to the spinal cord is very exciting. To our knowledge, this is the first time a sensory change of this magnitude has been reported in patients with complete spinal cord injury following a stem cell transplantation. We clearly need to collect more data to establish efficacy, but we are encouraged. We are pushing ahead with our trial and plan to dose the first patient with an incomplete injury soon."
Patients in the study's first cohort all suffered a complete injury to the thoracic (chest-level) spinal cord. In a complete injury, there is no neurological function below the level of injury. All three patients were transplanted four to nine months after injury with a dose of 20 million cells at the site of injury. The surgery, immunosuppression and the cell transplants have been well tolerated by all the patients. There were no abnormal clinical, electrophysiological or radiological responses to the cells, and all the patients were neurologically stable through the first six months following transplantation. Changes in sensitivity to touch, heat and electrical stimuli were observed in well-defined and consistent areas below the level of injury in two of the patients, while no changes were observed in the third patient. Importantly, tests of perception of different sensory stimuli as well as measures of electrical impulse transmission across the site of injury correlate with the clinical examination, providing independent and objective confirmation of the changes in sensory function.