Approved Long-Term Treatments
The first three long-term MS treatments to be approved were dubbed the "A-B-C" drugs because of their brand names: Avonex®, Betaseron®, and Copaxone®. These are interferon beta-1a, interferon beta-1b, and glatiramer acetate, respectively. All were approved by the Food and Drug Administration (FDA) for treating RRMS. These drugs have been approved by the Food and Drug Administration (FDA) for treating either RRMS or all relapsing forms of MS. Some of the drugs have also been approved for “clinically isolated syndrome” (CIS), which refers to the initial symptom a patient reports prior to a diagnosis of MS.These drugs have been used for several years and research shows that people are doing well on these medications for long periods of time (some for more then 20).
The fourth drug to be approved by the FDA was Novantrone® (mitoxantrone), and this was the first drug indicated for RRMS, SPMS and worsening RRMS. News then arrived of a fifth FDA-approved drug Rebif® (interferon beta-1a) for relapsing types of MS. This is the same drug as Avonex, but is injected differently and in more frequent and higher doses.The sixth drug now available for MS is Tysabri® (natalizumab), which is approved for relapsing forms of MS.
Several large clinical trials have been conducted to study each of these drugs separately for their effects on MS. Although differences exist in study design and specific findings, trials generally showed these common results:
Reduced the number of relapses
Reduced the severity of relapses
Reduced the development of new areas of inflammation as seen on MRI
Showed some evidence of delaying short-term disease progression
Each of the approved treatments has side effects which are usually manageable. At this time Novantrone is the only drug that has a set limit of doses, which is necessary to avoid cardiotoxicity (heart damage). After its original approval, Tysabri was temporarily suspended after two individuals (taking Tysabri in combination with Avonex) developed progressive multifocal leukoencephalopathy (PML), which is an often-fatal viral infection of the brain. Since that time, Tysabri has been re-approved and patients are closely monitored through the “TOUCH Prescribing Program.” The other drugs appear safe provided the person taking the drug is not experiencing any adverse effects and blood tests continue to be normal.