As of January 2013, the FDA has approved nine disease-modifying drugs or therapies (listed below) for the treatment of relapsing forms of multiple sclerosis, including secondary-progressive MS in patients who still experience relapses.  One of the drugs, Novantrone, is specifically approved to treat secondary-progressive MS.  Four drugs, Avonex, Betaseron, Copaxone, Extavia, are approved for use in patients who have experienced a first clinical episode, called clinically isolated syndrome...