A clinical trial to test the safety of a stem cell treatment for amyotrophic lateral sclerosis (ALS), the most common form of motor neurone disease, suggests that the new therapy is safe and well-tolerated. Encouragingly, one of the 12 patients participating in the study showed some improvement, although the trial was not designed to test the treatment's efficacy.
Professor Jonathan Glass, of Emory University Medical School in the USA, and the lead author of the study, said: 'For these first 12 patients, we have met the objective of the trial, demonstrating safety for both the procedure of intraspinal injection and the presence of the neural stem cells in the spinal cords of ALS patients'.
In the trial, the researchers used a 'risk escalation' design where the first patients treated would have the least function to lose should the operation have led to serious complications.
Patients were split into groups of three, with each successive group being exposed to an increasing risk. The first group consisted of patients who had lost the ability to walk, and they received injections on only one side of their spine. The following groups consisted of patients who were injected on both sides of their spine, and who could walk. In the last group of patients, one patient showed improvement after treatment.
Although some side effects were observed, these appeared to be due to the immunosuppressive drugs patients were prescribed rather than the stem cell injections. The published study includes data from patients up to 18 months after the original surgery.
NeuralStem, a US biotech company, designed the neural stem cell treatment. Dr Karl Johe, NeuralStem chairman, and co-author of the study said that the study showed that the company's 'experience in the lumbar spinal cord has been overwhelmingly positive'. He added that the company was already trialling its therapy in the cervical spinal cord (the neck area) to better treat the breathing problems of ALS patients.
However, Dr Eva Feldman, director of research at the ALS clinic at the University of Michigan Health System, who was involved in the study said: 'We must be cautious in interpreting this data, as this trial was neither designed nor statistically powered to study efficacy'.