Intense immunosuppression followed by AHSCT is significantly superior to MTX in reducing MRI activity in severe cases of MS. These results strongly support further phase III studies with primary clinical endpoints. The study was registered as EUDRACT No. 2007-000064-24.

This study shows that AHSCT with a BEAM/ATG conditioning regimen has a sustained effect in suppressing disease progression in aggressive MS cases unresponsive to conventional therapies. It can also cause a sustained clinical improvement, especially if treated subjects are still in the relapsing-remitting phase of the disease.

Intense immunosuppression followed by autologous hematopoietic stem cell transplantation (AHSCT) has been widely used in the last 20 years for the treatment of aggressive forms of autoimmune disorders, especially multiple sclerosis (MS). All clinical studies, although small and uncontrolled, demonstrate a great efficacy of this procedure in halting inflammation and disease activity, even in those patients affected by "malignant forms" of MS. The long-term follow-up has also revealed the possible maintenance of positive results in the course of time, and this evidence is supported by immunological data that suggest the possibility of a resetting of the immune system after AHSCT. The safety of AHSCT has improved in the last years, but the transplant related mortality is still nowadays of about 1-2 %, pointing out that a careful selection of patients to submit to AHSCT is mandatory. The long clinical experience allowed to identify the ideal candidate: a young patient, with a short disease duration, with recurring and disabling relapses and the presence of inflammatory activity on brain magnetic resonance scans, unresponsive to approved therapies. A large, randomized clinical study comparing AHSCT with the best approved therapies is still necessary to confirm the role of transplantation in MS treatment.

A low-intensity conditioning regimen with AHSCT has a profound effect on MRI inflammation and relapses, but is not able to completely abrogate MRI activity and disease progression of aggressive RRMS.

Background and purpose The best therapeutic approach for aggressive relapsing–remitting multiple sclerosis remains unknown. The objective was to compare the efficacy and safety of autologous haematopoietic stem cell transplantation (aHSCT) and alemtuzumab in aggressive relapsing–remitting multiple sclerosis. Methods The time to first relapse, time to confirmed disability worsening, time to first evidence of magnetic resonance imaging (MRI) activity and time to first evidence of disease activity were compared between the two treatment groups. Secondary outcomes included the 12, 24 and 36 month annualized relapse rate (ARR) and the 6‐month confirmed Expanded Disability Status Scale (EDSS) changes at months 12 and 24. Results Fifty‐seven patients treated with aHSCT (n = 25) or alemtuzumab (n = 32) were included. At baseline, aHSCT patients had a higher EDSS (median score 6 vs. 3; P < 0.001), higher ARR (mean ARR 3.2 vs. 1.7; P = 0.001) and a higher number of baseline T1 gadolinium‐enhancing lesions on MRI (mean number 15.5 vs. 1.6; P < 0.001). NEDA‐3 (no evidence of disease activity) status was more frequently achieved in aHSCT‐treated patients than in alemtuzumab‐treated patients [75% vs. 56% of patients at the end of the observation period; hazard ratio (HR) 0.27, 95% confidence interval (CI) 0.08–0.84; P = 0.023]. aHSCT significantly reduced the risk of relapse (relapse‐free survival 84% vs. 69%; HR 0.13, 95% CI 0.02–0.63; P = 0.012) and MRI activity (MRI‐activity‐free survival 85% vs. 59%; HR 0.13, 95% CI 0.03–0.59; P = 0.009). The ARR at 36 months was significantly lower in the aHSCT group (0.05 vs. 0.35, P = 0.02). A significant effect of aHSCT in promoting EDSS improvement compared with alemtuzumab was noted (P = 0.035). Conclusions Alemtuzumab and aHSCT are effective treatment choices for aggressive multiple sclerosis. aHSCT seems to be superior to alemtuzumab in inducing complete disease control and in promoting short‐term disability improvement.