Mini-Autologous Hematopoietic Stem Cell Transplantations as a New Treatment Modality for Multiple Sclerosis Patients

Abstract

Conventional therapies do not provide satisfactory control of multiple sclerosis (MS) due to their inability to eradicate self-specific T cell clones. Recently, high-dose immunosuppressive therapy with autologous hematopoietic stem cell transplantation (AHSCT) was proposed as a new and promising therapy for MS patients. Taking into account the information about high risk of transplant-related mortality and severe side effects of myeloablative conditioning regimens, the rationale to use non-myeloablative regimens sounds reasonable. The goal of our research was to study the safety and efficacy of mini-AHSCT in MS patients. Fifty three patients with MS (secondary progressive – 16 patients, primary progressive – 12, progressive-relapsing – 3 and relapsing-remitting – 22) were included in this study (mean age - 30.0, range: 17–47; male/female – 23/30). The conditioning regimen included reduced or modified BEAM. Median EDSS at base-line was 4.0 (range 1.5 – 8.0). The median follow-up duration was 7 months (range 6 – 20 months). Neurological and quality of Life (QoL) evaluation was performed at baseline, at discharge, at 3, 6, 9, 12 months, and every 6 months thereafter AHSCT. MRI examinations were performed at baseline, at 6, 12 months, and at the end of follow-up. Transplantation procedure was well tolerated by the patients with no transplant-related deaths. Among 29 patients included in the efficacy analysis 15 patients (52%) experienced clinical stabilization; 14 (48%) – improvement. EDSS improved by 0.5 points in 11 patients, by 1.0 points in 2 patients, by 2.0 points in 1 patient. One patient progressed after 6 months stabilization. No active, new or enlarging lesions were registered in patients without disease progression. Out of 27 patients included in QoL analysis 21 exhibited QoL improvement and 4 – stabilization during the follow-up; QoL worsened in 2 patients. All the patients without disease progression were off therapy throughout the post-transplant period. In conclusion, mini-AHSCT may be considered as a new, safe and effective treatment for MS. The results of mini-AHSCT in MS patients are promising both in terms of clinical and patient-reported outcomes. The collection of long-term follow-up data is worthwhile to verify these findings. The rationale of evolution from myeloablative to non-myeloablative transplant regimens should be confirmed by the further studies.