How Does It Work?

Since I started writing about my Tysabri Travels, I’ve received a number of emails with questions about the drug and its efficacy and side effects. When I visit a number of M.S. discussion boards, one in almost every ten postings is about Tysabri. Folks in my personal life also ask about the drug, how it is administered and how it works. It’s a hot topic. 

I frequently say that it is critical for all of us to be advocates in our own health (being selective in our choice of doctors, requesting copies of our MRI photos and reports, researching treatments and other issues with our disease).  One of the biggest questions I hear relates to how Tysabri is different from the other CRAB drugs.  From the Tysabri web site:

TYSABRI is different and it works differently.

·TYSABRI is an antibody, not aninterferonorglatiramer acetate. An antibody is a protein made by yourimmune system

·TYSABRI is thought to inhibitwhite blood cellsfrom getting into the brain and attacking nerves

·Keeping these cells from attacking nerves is believed to result in fewer brain lesions that cause MS symptoms

·The way in which TYSABRI works has been studied, but the exact way that TYSABRI works is not fully known

The easiest way I explain how it works is that there is a barrier (it’s called the BBB – Blood Brain Barrier) and Tysabri works to stop white blood cells from crossing that barrier. If the white blood cells don’t cross the barrier, they can’t attack the brain. If the cells don’t attack the brain, myelin isn’t damaged, nerves aren’t exposed, and new lesions aren’t formed. 

Tysabri doesn’t work to treat the symptoms of M.S., despite the fact that many, many patients see improvements after treatments. I understand that some patients see relief from their “new normal symptoms” because the brain is being given a chance to heal (since it isn’t under attack anymore) and sometimes this healing resolves some or all of an M.S. patient’s symptoms either temporarily or semi-permanently. The main goal of Tysabri is to prevent future attacks, limit the number of relapses, and reduce a person’s level of disability from M.S.

Like with any drug, there are risks associated with Tysabri. We’ll talk about those in a future article, as we continue to ride the Ty-Train together.