Autologous haematopoietic stem cell transplantation in multiple sclerosis: outcomes and predictors from German real-world data

Background Autologous haematopoietic stem cell transplantation (aHSCT) represents a treatment option for highly aggressive multiple sclerosis (MS). Here, we report outcome analyses from the two largest German centres performing aHSCT in MS. Methods In this retrospective analysis, people with (pw) MS who underwent aHSCT between 2007 and 2025 were included. Outcomes comprise no evidence of disease activity (NEDA-3), 3-month confirmed disability changes on the Expanded Disability Status Scale and transplantation-related mortality (TRM). Predictors of treatment response were evaluated according to the European Committee for Treatment and Research in Multiple Sclerosis and the European Society of Blood and Marrow Transplantation consensus criteria. Results A total of 109 pwMS were included: 55 (50.5%) with relapsing-remitting MS (RRMS), 23 (21.1%) with secondary progressive MS (SPMS) and 31 (28.4%) with primary progressive MS (PPMS). Median follow-up after aHSCT was 20.1 months. Overall, 82.8% (SE 4.9%) of pwMS maintained NEDA-3. PwRRMS had significantly higher NEDA-3 rates (Kaplan-Meier (KM) estimate 91%, SE 5%) than those with SPMS (KM 80.1%, SE 10.5%, p=0.018) or PPMS (KM 70.6%, SE 11.4%, p=0.035). Patients meeting core consensus criteria achieved NEDA-3 more often (KM 94.4%, SE 5.4%) than those meeting the extended criteria (KM 84.4%, SE 8.5%, p=0.199) or those outside the criteria (KM 73.7%, SE 8.8%, p=0.004). In progressive MS, a disease duration of <5 years indicated a potential prediction of NEDA-3 stability. TRM was 0.9% (n=1/109). Conclusions In this heterogeneous cohort, comprising a substantial proportion of people with progressive MS, aHSCT provided sustained NEDA-3 stability and a marked reduction in inflammatory disease activity, particularly in RRMS, with a potential benefit in progressive MS.