How effective is the drug Tysabri for MS?

Tysabri is the brand name of natalizumab, a disease modifying therapy. It is classed as a highly effective drug for people with more active relapsing remitting multiple sclerosis (RRMS). It was the first highly effective drug of its kind, first approved by NICE in 2007.

Trials show that people with RRMS taking Tysabri had around 70 per cent fewer relapses than those taking a placebo. People with highly active MS showed a decrease of 81 per cent in relapses as a result of taking the drug.

MRIs from clinical trials showed people taking Tysabri had fewer, smaller, or no new areas of active MS lesions. It may also help slow down the build-up of disability associated with MS, for example, less disabling relapses, less activity and inflammation, and less acquired disability.

For many, it is a very effective drug. It is taken monthly, by infusion (directly into the vein), at an infusion centre.

To answer the question, do people get better when taking Tysabri, it is important to note that ultimately you will still have MS. However, you can experience significant improvements from a relapse. If you experience disabling relapses one after another, this can be really quite debilitating. Tysabri is a treatment to stop these relapses and reduce the severity of any that are experienced. In doing this, it can help to prevent any acquired disability.

In summary, medications that modify the course of the disease are aiming for no relapses, therefore no further acquired disability and symptoms, no inflammation and ultimately no evidence of disease activity (NEDA).