Efficacy and safety of mesenchymal stem cell therapies for patients with multiple sclerosis: a systematic review and single arm meta-analysis

Abstract

Background & Aim Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system, characterized by an aberrant activation of the immune system and combining demyelination with neurodegeneration. Studies on experimental models of MS revealed immunomodulatory and immunosuppressive properties of mesenchymal stem cells (MSC). However, the efficacy and safety of these treatments are not yet fully understood. Therefore, we performed a meta-analysis of available single-arm studies using clinical trials using MSC in MS patients. Methods, Results & Conclusion Methods We searched MEDLINE, EMBASE, and the Cochrane database for studies of stem cell therapy in patients with MS from its inception through November, 2018. The articles included in the search were restricted to the English language, studies using MSC therapies for treating MS. Results Fourteen studies included in the meta-analysis. The pooled mean difference in Expanded Disability Status Scale (EDSS) scores from baseline to follow-up points was -0.31 points (95%CI: −0.58 to −0.03, I2=53.7%) decreased and the pooled mean difference in size of gadolinium-enhancing lesions on an MRI was decreased by -0.24 (95%CI: -0.56 to 0.08, I2=0%) at 12-month follow-up. The pooled incidence rate of infection was 35.4% (95%CI, 32.9-37.8%) during 12-month follow-up. Conclusions Disease stability was determined by less than a 1.0 point change in EDSS in the 12 months preceding entry into the treatment phase of the study, and lack of gadolinium-enhancing lesions on an MRI and by a stable MRI disease burden over the same period. The EDSS score changes was relatively low even it was statistically significant. The published data suggest that MSC therapy for patients with MS might not be judged as effective based on the current evidence. Transient risks remain associated with the MSC injection was relatively high. Clinical benefits of MSC for MS patients need further investigation and reevaluation to test the well-designed large clinical trials. This research was supported by a grant (18172MFDS182) from the Ministry of Food & Drug Safety in 2018.