MS Neurologist Argues for Continued Use of Natalizumab as Disease Treatment

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In a recent study of more than 1,200 patients with multiple sclerosis (MS), a research team reported that treatment with the drug natalizumab (Tysabri) could lead to a tenfold increase in the levels of blood antibodies associated with a virus causing a rare but severe brain disease known as progressive multifocal leukoencephalopathy (PML).

The study, “Therapy with natalizumab is associated with high JCV seroconversion and rising JCV index values,” was published in the journal Neurology: Neuroimmunology and Neuroinflammation and recently discussed in a Multiple Sclerosis News Today article.

The John Cunningham virus (JCV) is responsible for PML development, especially in individuals who have a weakened immune system or are undergoing immunosuppressive treatments. PML leads to the destruction of white matter in the brain.

However, increasing levels of JCV-antibodies do not necessary translate into a higher risk for patients to develop PML, as neurologists Adil Javed, MD, PhD, and Anthony Reder, MD, from the University of Chicago, said in a corresponding editorial.

Following the study publication, Dr. Javed highlighted the benefits of natalizumab as therapy for MS auch_029791-1nd explained its mechanism of action in a University of Chicago news release. “MS is an autoimmune disease, meaning that it’s a disease of mistaken self identity. The body’s own immune system attacks myelin, an essential layer of insulation around nerve fibers. Without this protective layer, neurons in the central nervous system misfire or fail to fire at all, causing muscle weakness, balance and coordination problems, i.e. disability” he said. “Natalizumab blocks migration of immune cells into the brain and thereby leads to an immunosuppressive state in the central nervous system. It’s by this mechanism that it prevents immune cells from destroying the body’s own myelin. Due to its potent effects on the immune system and the demonstrated high efficacy of the drug in clinical trials in comparison to the older agents, natalizumab was a game changer when it came out in 2004. MS neurologists all thought, ‘why shouldn’t every MS patient be on this drug?’”

When asked if the increase in JCV antibodies in MS patients meant that they were 10 times more likely to develop PML, Dr. Javed said: “Absolutely not. When we see rising antibody levels, or titer, we assume that there must be more replication of the virus. The higher the replication rate of the virus, the higher the chance that the virus could infect brain cells. But this is all based on assumptions and circumstantial evidence. There has never been a good study that shows that rising antibody titers are proportionally correlated with higher viral replication or load. The fact remains that even though JC virus-antibody levels rise over time while on natalizumab therapy, the risk of PML over time continues to remain relatively low.”

It is believed that patients under natalizumab therapy for two years have a risk of  less than 1 in 1,000 of developing PML.

“Based on the finding of a 10-fold increase in the JC virus antibody levels during natalizumab therapy, patients should not stop taking the medication out of fear that now they have a 10-fold increase risk of getting  PML. All this study says is that more monitoring is needed. Your neurologist can track your antibody levels, and discuss with you the risk associated with the medication over time,” Dr. Javed said.

“It’s all about risk and benefits. With proper monitoring over time, it’s up to the physician and patient to determine at what point the risks outweigh the benefit and what point the medication should be stopped. If you’re negative for the JC virus, then the risk for developing PML is incredibly low and the benefits of natalizumab are huge. This medication could keep a patient very stable over a long period of time,” he added. “If you are JC positive, and your titers are low, you could still stay on the medication as long as your titers remain low.”

Dr. Javed concluded: “In my practice, if JC titers reach a certain threshold and continue to rise, I have advised patients to switch to a different MS medication. After informing the patients of the risks and benefits, it’s ultimately their choice. There are many patients who continue to stay on natalizumab irrespective of JC virus-antibody levels, due to their own personal experience with the high effectiveness of this agent.”

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  1. Shirley says:

    UNTIL MS is researched properly … It cannot be determined as an “Autoimmune” condition. They have ABSOLUTELY NO PROOF that the immune system attacks itself. It has just been a theory for decades. But, there is now proof that the brain is NOT immune protected. Please collaborate with researchers instead of trying to kill us. This is a great read and must be read by all those with this so called MS diagnoses.

    • Judy Pentz says:

      Thanks Shirley for pointing that out. I’ve known people cured of MS by having their CCSVI properly treated and my dear friend Angela who lost everything to PML due to Tysabri. Her life, her personality, marriage and everything else destroyed by doctors who refuse to acknowledge over 600 cases of PML where over a third of people have died. they have never proven the auto immune theory either. I loathe articles like this drug pushing Tysabri doctor’s.

  2. I just had my 20th infusion of Tysabri, and since I tested positive for the JCvirus, I have been researching the 3 available oral medications for MS, to replace this treatment going forward. Aubagio is the only pill out of the 3 with NO reported cases of PML, as compared to Gilenya or Techfidera. Prior to taking Tysabri, I was taking injections injections of Rebif prior to my journey with Tysabri, so I didn’t want to jump back in the injection scenario. My last 2 years of taking Tysabri has been very good in maintaining my MS relapses and exacerbation’s, but the report of PML is not a risk that I am willing to take. I just want to wake up one morning and say to the world, “Yes, I used to have MS, but not anymore.”

    • Colleen says:

      Have you looked at Rituxan? I have friends who have switched and have no relapse in between therapies. I am planning on switching to the Ocrelizumaub when it comes out in 2017 if my titres stay low for Tysabri. In the meantime, I have switched to every 6 weeks instead of every 4. I am on infusion #36 and have been positive from the start with a low titre of around 0.2. I’m praying it stays that low until I am able to switch.

  3. Colin Hinton says:

    Hi all , I have been on Tysabri for two an have years and have now gone positive. I was advised to stop Tysabri , which I have now done . I need to make a choice between Gilenya or Techfidera . I am male , 46 yo and have four kids . Tysabri has been awesome , so now I’m quite scared of going backwards and the side affects . Reading your posts now gives me more medications to discuss with my Nero. Steve very interested with your comment about Aubagio , I will research some more on this drug .
    Cheers Colin. ( Melbourne Australia )

    • Check with your neurologist on Aubagio, and let me know their response. I still find it strange that these pharmaceutical companies and the world governments can’t just collaborate with each other, and find a cure for ALL. I realize that every case of MS is different, but cause and effect is the same. I pray this will be beneficial to our Multiple Sclerosis journey through life.

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