Multiple sclerosis (MS) is a neurologic condition in which communication between the brain and other parts of the body is affected, causing muscle weakness in the arms and legs and problems with coordination and balance. Initial symptoms of MS include blurred vision, color blindness, or blindness in one eye and typically appear between 20 and 40 years of age. Severity of symptoms varies by individual, ranging from complete paralysis to speech impediments to dizziness.
Classification of Disease
MS is categorized based on disease progression and pattern as relapsing-remitting MS, primary-progressive MS, secondary-progressive MS, or progressive-relapsing MS. Choice of treatment is dependent on the type and characteristics.
Approved Treatments
There is currently no cure for MS, but certain drugs have demonstrated decreased relapse rates and slower progression to disability. The majority of drugs are approved for the treatment of relapsing-remitting MS.
Interferons
Three interferon beta medications are approved for the treatment of relapsing-remitting MS: Betaseron, Avonex, and Rebif. All medications are injected into the muscle every other day or three times weekly, depending on the drug. Response rates vary by individual, but all interferon beta medications have been shown to improve impairment and disability in clinical trials. However, side effects are significant and include injection site reactions, flu-like symptoms, depression, and liver function test abnormalities.
Copaxone
Copaxone (glatiramer acetate) is a mixture of amino acids similar to myelin protein, which serves as an insulator to the nerves. Copaxone has been shown to reduce relapse rates and improve disability in individuals with MS. Like the interferons, side effects associated with Copaxone are significant and include injection site reactions, chest pain, flushing, shortness of breath, palpitations, and anxiety.
Tysabri
Tysabri (natalizumab) is approved for relapsing forms of MS and has been shown to reduce relapse rates, reduce formation of lesions in the brain, and improve health-related quality of life. However, use of Tysabri may cause a potentially fatal neurologic disease called progressive multifocal leukoencephalopathy. For this reason, Tysabri should be used with caution, following the strict guidelines of the manufacturer, and is available only at certain centers where individuals can be properly monitored. Other side effects include increased risk of melanoma and potential liver injury.
Novantrone
Novantrone (mitoxantrone) is approved for relapsing-remitting or progressive forms of MS. However, Novantrone should only be used when other therapies have failed or in those with rapidly progressive disease due to associated cardiac toxicity.
Investigational Treatments
Agents that are currently under investigation for MS treatment include alemtuzumab, azathioprine, cyclophosphamide, daclizumab, fingolimod, fumarate, intravenous immunoglobulin, laquinimod, rituximab, and teriflunomide. Although some preliminary studies have shown promise, larger studies are needed to determine if any of these agents are effective for the treatment of MS.
Tags: been shown, relapse rates, side effects, approved treatment, approved treatment relapsing-remitting, been shown reduce