For patients suffering from the relapsing-remitting form of MS, Tysabri is an effective treatment. But most doctors are recommending it be used only to treat cases of rapidly-evolving and severe relapsing–remitting multiple sclerosis or (RES). This is because of side effect possibilities of Multiple Sclerosis Tysabri treatment, which are not insignificant. RES is characterized by experiencing two or more relapses in a year period, and one or more gadolinium-enhancing lesions as seen on an MRI of the brain. Usually, the initial disease modifying therapy for relapsing-remitting multiple Sclerosis will be an interferon beta-1a, interferon beta-1b or Glatiramer Acetate based treatment.
MS Tysabri treatment is actually a natalizumab treatment. Tysabri is the brand name of the drug.

 

Multiple Sclerosis Tysabri treatment approved after two trials showed evidence of effectiveness for RMMS patients

 

The original FDA approval of MS Tysabri infusion to treat relapsing forms of MS was based conclusions drawn from two controlled studies that were randomized and highly controlled. These studies became known as the AFFIRM and SENTINEL trials.
In the AFFIRM trial, over 900 patients with RMMS were randomly given Multiple Sclerosis Tysabri treatment or placebo intravenously. This was done for two years every 4 weeks. The MS Tysabri treatment showed a 68 percent reduction in annual relapse rates compared with placebo treatment. The difference was 0.26 vs.0.81.
In the SENTINEL trial, over 1000 patients with relapsing MS who were still experiencing disease activity while receiving interferon beta-1a treatment were randomly chosen to also receive MS Tysabri infusions or placebo every four weeks. All of the participants continued to receive interferon beta-1a throughout the trial. The study was stopped about a month early because two of the patients developed progressive multifocal leukoencephalopathy. The MS Tysabri treatment showed a 54 percent reduction in annualized relapse rate compared with placebo after one year.

 

Progressive Multifocal Leukoencephalopathy (PML) the main worry with Multiple Sclerosis Tysabri treatment

 

The main concern about the Multiple Sclerosis Tysabri treatment is the remote possibility of developing Progressive Multifocal Leukoencephalopathy as a side effect of the infusions. The fact is that three people did develop Progressive Multifocal Leukoencephalopathy while using Tysabri. Two of them died and one became severely disabled. Tis caused the drug to be pulled from the market temporarily. But after new monitoring procedures for PML became available, the drug was allowed back on the market. And a crystal clear link was never really established. Before considering MS Tysabri, careful consideration should be given and a discussion with your doctor is certainly in order. And if you do proceed, careful monitoring is advised by all means.