Pilot trial of intravenous autologous culture-expanded mesenchymal stem cell transplantation in multiple sclerosis

Background: Mesenchymal stem cells (MSCs) exhibit immunomodulatory, tissue-protective, and repair-promoting properties in vitro and in animals. Clinical trials in several human conditions support the safety and efficacy of MSC transplantation. Published experience in multiple sclerosis (MS) is modest. Objective: To assess feasibility, safety, and tolerability and explore efficacy of autologous MSC transplantation in MS. Methods: Participants with relapsing-remitting multiple sclerosis (RRMS) or secondary progressive multiple sclerosis (SPMS), Expanded Disability Status Scale score 3.0-6.5, disease activity or progression in the prior 2 years, and optic nerve involvement were enrolled. Bone-marrow-derived MSCs were culture-expanded and then cryopreserved. After confirming fulfillment of release criteria, 1-2 x 10(6) MSCs/kg were thawed and administered IV. Results: In all, 24 of 26 screened patients were infused: 16 women and 8 men, 10 RRMS and 14 SPMS, mean age 46.5, mean Expanded Disability Status Scale score 5.2, 25% with gadolinium-enhancing magnetic resonance imaging (MRI) lesions. Mean cell dosage (requiring 1-3 passages) was 1.9 x 10(6) MSCs/kg (range, 1.5-2.0) with post-thaw viability uniformly 95%. Cell infusion was tolerated well without treatment-related severe or serious adverse events, or evidence of disease activation. Conclusion: Autologous MSC transplantation in MS appears feasible, safe, and well tolerated. Future trials to assess efficacy more definitively are warranted.