The recent in this field is the use of a combination of chemo and stem cells. For more on this approach, please see the recent article entitled "Novel Multiple Sclerosis Treatment Uses Chemo And Stem Cell Therapy To Restore Immune System":
Mitoxantrone – a chemotherapy drug indicated for worsening forms of relapsing MS and secondary progressive MS. It is given by intravenous infusion every 3 months. Because this drug can be very toxic, it can only be given in a limited number of doses over the course of someone’s life.
Mitoxantrone works by suppressing the immune system and reducing the overall numbers of immune cells that could be causing inflammation in MS
Mitoxantrone is associated with many side effects including cardiotoxicity
Mitoxantrone is currently the only chemotherapeutic agent approved for treatment of MS in the United States, while in parts of Europe azathioprine is approved and widely used for MS treatment. Other chemotherapeutics that have been tested in MS to date include cyclophosphamide, methotrexate, cladribine, and the mAbs alemtuzumab and rituximab.
I wonder in USA but in the EU Sativex is approved for certain types of multiple sclerosis patients. Details are in this document of the EMEA (The European equivalent to FDA)