A phase I/IIa clinical trial of autologous hematopoietic stem cell transplantation in amyotrophic lateral sclerosis

Objective: To verify the safety and potential effect on ALS progression of a low-intensity immunosuppressive regimen followed by autologous hematopoietic stem cell transplantation (aHSCT) in amyotrophic lateral sclerosis (ALS) patients. Methods: ALS eligible patients underwent a set of clinical and laboratory evaluations at T-4 (screening), T-1 (pre-treatment visit), and for the 12 consecutive months after treatment (T3, T6, T9, T12). We evaluated the tolerability of the procedure, its efficacy on clinical course and quality of life (QoL). Results: Eight of the 11 ALS patients enrolled received the established immunoablative protocol. The procedure was well tolerated and side effects were those expected. One patient died 4 months after the conditioning regimen and another patient underwent tracheotomy just before T3 for a sudden respiratory failure, but he is still alive 4 years after the procedure without being ventilated any more. A third patient died 10 months after conditioning. In the other cases, there was no statistical difference in all functional measures and QoL pre- and post-treatment; however, a transitory slopes’ reduction of ALSFRS-R and seated SVC% after the conditioning procedures was reported. Moreover, although not statistically significant, trends of reduction of CD4 + and increment of CD8 + were found. Conclusions: aHSCT was overall well tolerated, but it was not followed by any significant modification in disease progression. Considering the negative results of this small trial, further studies aimed to evaluate the possible efficacy of the aHSCT using a higher-intensity regimen should be carefully and with caution evaluated.