Stem cell transplantation may be a safe avenue for amyotrophic lateral sclerosis

Written by Elena Conroy

A new phase II clinical trial for ALS demonstrated that transplantation of human stem cells may be a safe option and does not accelerate the progression of the disease

To test the safety of a stem cell treatment, amyotrophic lateral sclerosis (ALS) patients received a spinal cord transplantation of human stem cells in a phase II clinical trial. The trial consisted in giving the participants escalating doses of the treatment and was carried out in multiple clinical centers. The study was recently published in Neurology, the medical journal of the American Academy of Neurology.

ALS is a disorder in which motor neurons in the brain and spinal cord degenerate. The disease results in progressive loss of muscle control, including breathing and swallowing, leading to death. There are currently no treatments that can stop the disease.

“Though there were two 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,” explained Jonathan D. Glass, a professor of neurology at Emory University School of Medicine in Atlanta and a member of the American Academy of Neurology.

The study involved 15 patients with ALS at three different university hospitals. The participants all presented their first ALS symptoms within two years from the start of the study. The cohort was divided into five treatment groups that received an increasing number of injections. The numbers of injections ranged from 10 to 40, and the number of cells injected ranged from two million to 16 million. The trial was open-label, so participants were aware they were receiving the active stem cell treatment.

All participants received bilateral injections into the cervical spinal cord between the C3 and C5 regions. The final group received injections into both the lumbar (L2-L4) and cervical cord through two separate surgical procedures. During the nine month follow-up, researchers collected information about side effects and measured progression of the disease using the ALS functional rating scale.

The results were positive with most of the side effects being related to temporary pain associated with surgery and to immunosuppressive medication. Two people developed serious complications related to the treatment. One patient developed spinal cord swelling that caused pain, sensory loss and partial paralysis and another patient developed central pain syndrome.

The participants’ functioning was compared to three historical control groups, and there was no difference in how fast the disease progressed between those who received stem cells and those who did not. However, Glass cautioned that a conclusion should not be made about effectiveness of the treatment from the small study.

“This study was not designed, nor was it large enough, to determine the effectiveness of slowing or stopping the progression of ALS,” commented Glass. “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,”

Sources:; Glass JD, Hertzberg VS, Boulis NM et al. Transplantation of spinal cord—derived neural stem cells for ALS. Neurology, doi: 10.1212/WNL.0000000000002889 (online before print) (2016)