- Two or more relapses in 18 months time on interferon (IFN), glatiramer acetate (GA), natalizumab or cytotoxic therapy with EDSS increase of 1.0 or greater for participants with EDSS at screening of 3.0 to 3.5 (0.5 or greater for participants with EDSS at screening of 4.0 to 5.5) sustained at least 4 weeks after at least one of these relapses OR one relapse on IFN, GA, natalizumab or cytotoxic therapy with EDSS increase of 1.5 or greater (1.0 for subjects with EDSS at screening of 5.5) sustained at least 4 weeks, together with MRI changes consistent with poor prognosis. More information on this criterion can be found in the protocol.