The transplantation of human neural stem cells appears to be generally safe in patients with amyotrophic lateral sclerosis (ALS), results from a small phase II trial indicate.
The results, however, should not be used to draw conclusions regarding the effectiveness of the treatment.
In order to examine the safety of the surgical procedure, Jonathan D. Glass, MD, of Emory University School of Medicine, and colleagues enrolled 15 patients with ALS in the open-label study at 3 academic centers. The participants were divided into 5 treatment groups, with all participants receiving bilateral injections (10-40) into the cervical spinal cord (C3-C5) and the final group receiving injections in both the lumbar (L2-L4) cervical spinal cord during 2 separate procedures.
Most adverse events were transient pain related to the surgical procedures and side effects from immunosuppressant drugs. Two patients experienced more serious adverse events: one experienced acute deterioration of neurologic function including spinal cord swelling, pain, sensory loss, and partial paralysis, and one patient developed central pain syndrome.
“Though there were 2 serious complications related to the treatment, the level of acceptable risk for treating patients with ALS, where the prognosis is poor and treatments are limited, is arguably higher than that for more benign disorders,” Dr Glass said in a statement.
Disease progression was measured by the ALS Functional Rating Scale-Revised, forced vital capacity, and quantitative measures of strength. In comparison to 3 historical control groups, there was no difference in mean rates of disease progression.
“This study was not designed, nor was it large enough, to determine the effectiveness of slowing or stopping the progression of ALS,” Dr Glass said. “The importance of this study is that it will allow us to move forward to a larger trial specifically designed to test whether transplantation of human stem cells into the spinal cord will be a positive treatment for patients with ALS.”