Long-term results of autografting persons with multiple sclerosis are better in those not exposed to prior disease-modifying therapies.

Introduction: Multiple sclerosis (MS) is a disabling disease that affects young adults. Treatments for MS have increased exponentially in number, efficacy and risk. Autologous hematopoietic stem cell transplantation (aHSCT) can change the natural history of the disease. To analyze if aHSCT should be done early in the course of the disease or after failing of other therapies, we have studied the long-term results of aHSCT in a cohort of persons with MS who were given, or not, immunosuppressive drugs before the transplant.

Materials And Methods: Patients with MS referred to our center for aHSCT between June 2015 and January 2023 were prospectively entered in the study. All phenotypes of MS were included (relapsing remitting, primary progressive and secondary progressive). The follow up was assessed with the patient reported EDSS score in an online form; only patients followed by three or more years were included in the analysis. Patients were divided into two groups: Given or not disease modifying treatments (DMT) before the aHSCT.

Results: 1132 subjects were prospectively enrolled. 74 patients were followed for more than 36 months, and the subsequent analysis was done in this cohort. The response rate (RR = improvement + stabilization) at 12, 24 and 36 mo was 84%, 84% and 58% respectively for patients not receiving prior DMT and 72%, 90% and 67% for patients receiving DMT. In the whole group, the EDSS score dropped from a mean of 5.5 to 4.5 at 12 mo, to 5.0 at 24 mo and to 5.5 at 36 mo, after the aHSCT. The EDSS score was on average worsening in patients before the aHSCT, but the transplant stabilized the EDSS score at 3 years in patients with prior exposure to DMT, whereas in persons not given DMT, the transplant resulted in a significant decrease (p = .01) of the EDSS score. This indicates a positive response in all patients given aHSCT, but significantly better in those not exposed to DMT before the graft.

Conclusion: The response to aHSCT was better for persons not exposed to immunosuppressive DMT before the transplant, thus suggesting that aHSCT should be done early in the course of the disease and probably before the treatment with DMT. Additional studies are needed to further analyze the impact of the use of DMT therapies before the aHSCT in MS, as well as the timing of the procedure.