5. If receiving disease-modifying medications (eg, interferons approved for MS, glatiramer acetate, natalizumab, fingolimod, or mitoxantrone), there must be no change in dose for at least 3 months prior to Baseline, and the subject must be willing to maintain this treatment dose for the duration of the study. If receiving AMPYRA® (dalfampridine, fampridine, 4 amino puridine), subject must be at a stable dose for at least 3 months prior to Baseline.