Hematopoietic stem cell transplantation for multiple sclerosis

Burt RK, Cohen B, Rose J, Petersen F, Oyama Y, Stefoski D, Katsamakis G, Carrier E, Kozak T, Muraro PA, Martin R, Hintzen R, Slavin S, Karussis D, Haggiag S, Voltarelli JC, Ellison GW, Jovanovic B, Popat U, McGuirk J, Statkute L, Verda L, Haas J, Arnold R. Arch Neurol. 2005 Jun;62(6):860-4. Review.

Abstract

Hematopoietic stem cell transplantation (HSCT) was proposed as a treatment for multiple sclerosis (MS) in 1995 based on favorable results in animal models including experimental autoimmune encephalomyelitis.1 These initial or first-generation trials were developed by medical oncology subspecialists, used malignancy-specific myeloablative transplantation regimens, and selected patients with secondary progressive MS with rapid progression of disability. In general, these trials suffered from higher than anticipated toxic reactions including treatment-related and disease-related mortality, continued loss of brain volume as seen on magnetic resonance imaging (MRI), and, at least in some patients, continued progressive disability despite marked attenuation or absence of gadolinium-enhancing lesions on MRI.

Learning from these experiences, second-generation transplantation trials for MS are using MS-specific nonmyeloablative transplantation regimens and selecting for active relapses despite the use of interferon treatment in patients with less accumulated disability. While still preliminary, results using second-generation nonmyeloablative HSCT regimens are encouraging with minimal treatment-related morbidity and improvement in Expanded Disability Status Scale (EDSS) scores. The following 3 variables seem important in predicting the benefit and minimizing the toxic effects from an autologous stem cell transplantation in patients with MS: the selection of patients who still have inflammatory disease (ie, gadolinium enhancement on MRI and/or frequent active relapses), treatment early in the course before the onset of significant irreversibly progressive disability, and the use of a safer lymphoablative but nonmyeloablative HSCT conditioning regimen.