The Importance of Long-Term Treatment for Multiple Sclerosis
Treatment with a long-term, disease-modifying therapy (DMT) is crucial for most patients with MS, since disease activity and damage continues within the CNS even when no new symptoms are present. When a patient begins a treatment regimen early in his or her disease course, disease activity is slowed. This not only reduces the number and severity of symptom flare-ups, as well as delays the progression of the disease (and possibly delays any related disability), but also reduces the number of active lesions that appear on an MRI.
A 21-year prospective study of individuals (with relapsing-remitting MS) who began therapy early in the disease found that they experienced a longer lifespan than those who did not begin treatment as early. Of those who didn’t start treatment early, MS-related pulmonary infection was the most common cause of mortality over the 21-year period.
At the present, all but one of the approved treatments are only available for individuals with relapsing forms of multiple sclerosis (RMS) – largely for those with RRMS – and some are also approved for clinically isolated syndrome, prior to the diagnosis of MS. In 2019, Mayzent® (siponimod) oral tablets and Mavenclad® (cladribine) oral tablets were approved to treat RMS as well as active secondary-progressive MS (SPMS), which is a more steady form of MS that follows RRMS, but still has relapses. These are the only DMTs to be approved in recent years for active SPMS. While both are approved for RMS and active SPMS, Mayzent is also approved for clinically isolated syndrome (CIS). Another DMT, Ocrevus® (ocrelizumab), is not only approved for RMS, but is the first long-term treatment to also be approved for primary-progressive MS (PPMS).
Additionally, Gilenya® (fingolimod), is the only DMT that is also approved for the treatment of children and adolescents, ages 10 through 17, with relapsing forms of MS. Young people under the age of 18 who are diagnosed with MS are referred to having “pediatric MS”; the vast majority (98 percent) of individuals with pediatric MS are diagnosed with the relapsing form of the disease. Research (including many clinical trials) is ongoing at a rigorous pace to find additional treatments for all forms of MS.
Given via self-injection:
- Avonex® (interferon beta-1a)
- Betaseron® (interferon beta-1b)
- Copaxone® (glatiramer acetate injection)
- Extavia® (interferon beta-1b)
- Glatopa® (glatiramer acetate injection)
- Mylan’s generic version of Copaxone® (glatiramer acetate injection)
- Plegridy® (peginterferon beta-1a)
- Rebif® (interferon beta-1a)
Given via intravenous (IV) infusion:
- Lemtrada® (alemtuzumab)
- Novantrone® (mitoxantrone)
- Ocrevus® (ocrelizumab)
- Tysabri® (natalizumab)
- Aubagio® (oral teriflunomide)
- Gilenya® (fingolimod)
- Mavenclad® (cladribine)
- Mayzent® (siponimod)
- Tecfidera® (dimethyl fumarate or DMF, formerly known as BG-12)
Getting early treatment and staying on one of the long-term DMTs for MS may also delay the rate of conversion from RRMS to secondary-progressive MS (SPMS). As noted earlier, this form of MS that follows RRMS exhibits a steady worsening, with or without relapses (or flare-ups). If flare-ups do occur, they usually do not remit fully. As mentioned in the previous section, without treatment, approximately half of individuals with RRMS convert to SPMS within 10 years. However, with the introduction of 17 DMTs since the first treatment became available in 1993, those taking a DMT experience a reduced or delayed conversion rate.
For more information on long-term treatments for MS and how to select the treatment that is right for you, please see MSAA’s S.E.A.R.C.H.™ program.
Individuals who experience a more steady progression of the disease from the onset, without periodic relapses and remissions, may be diagnosed with primary-progressive MS (PPMS). To date, only one disease-modifying therapy (Ocrevus) has been approved for the long-term treatment of this form of MS, although many experimental medications are being studied with PPMS in clinical trials.