There are numerous medications that have been approved by the U.S. Food and Drug Administration (FDA) for the treatment of relapsing forms of MS, including relapsing-remitting MS (RRMS). All have been shown to reduce the number of relapses (also called attacks or exacerbations) and number of new lesions (also called plaques or scars) on magnetic resonance imaging (MRI), and they may also slow disease progression. Most MS experts recommend that people consider starting one of these medications as soon as the diagnosis of RRMS has been confirmed.
Of these medications, seven are injectable (Avonex®, Betaseron®, Copaxone®, Extavia®, Glatopa™, Plegridy®, Rebif® and Zinbryta™ [WITHDRAWN FROM THE MARKET - MARCH 2, 2018]), three are oral (Aubagio®, Gilenya® and Tecfidera®), and three are infused (Lemtrada™, Novantrone® and Tysabri®).
Novantrone is approved specifically for people with worsening RRMS — in other words, those whose RRMS is progressing in spite of treatment with one of the first-line medications -- as well as those with secondary-progressive MS. Lemtrada is approved for people with relapsing forms of MS who have had an inadequate response to at least two other disease-modifying therapies.