For MS Patients, New Guidelines for Controlling Rare Brain Infection Risk Under Tysabri Treatment

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multiple sclerosis patients treated with Tysabri

The European Medicines Agency Pharmacovigilance Risk Assessment Committee (PRAC), responsible for assessing and monitoring safety issues for human medicines, completed a review on the risk for progressive multifocal leukoencephalopathy (PML) in multiple sclerosis (MS) patients treated with the medicine Tysabri (natalizumab). The issued guidelines have the objective of minimizing patients’ risk.

Recently, a study titled “Therapy with natalizumab is associated with high JCV seroconversion and rising JCV index values,” published in the online issue of the journal Neurology, Neuroimmunology and Neuroinflammation, reported that MS patients treated with Tysabri (natalizumab) have an increased risk of developing high levels of antibodies associated with a virus that can cause the rare, but very serious, brain infection PML.

MS neurologist Adil Javed, MD, PhD, and Anthony Reder, MD, from the University of Chicago, emphasized the benefits of natalizumab as a therapy for MS.

They said early detection and treatment of PML, in the asymptomatic stages of the disease, were shown to be crucial for limiting the degree of brain damage and disability.

Hence, since asymptomatic cases of PML are easily detected through magnetic resonance imaging (MRI) scans, PRAC recommends more frequent MRI scans (every three to six months) in patients at higher risk of PML, namely MS patients who have antibodies against John Cunningham virus (a sign that a person has been exposed to the virus), are undergoing treatment with Tysabri for at least two years, and were submitted to previous immunosuppressant medicines before starting on Tysabri. All three factors, once present in the same patient, establish them at a higher risk for PML development.

Results from clinical trials suggested that the risk for PML is small, and even lower than previously estimated: antibody index values of 0.9 or less, increasing significantly in patients with index values above 1.5 who are undergoing treatment with Tysabri for longer than two years. Considering these results, the PRAC guidelines note that patients at higher risk of PML have a high antibody index and are undergoing Tysabri treatment for more than two years.

PRAC recommends that in patients at higher risk of developing PML, Tysabri treatment should be carefully evaluated and the medication only continued if patient benefits clearly outweigh the risks. Patients with a low antibody index and no use of immunosuppressant drugs before initiating Tysabri should also be carefully monitored, and undergo an antibody test every six months after they have been on Tysabri therapy for a period longer than two years.

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  1. James says:

    Scenario: JC positive. With an index of 2.1
    All MRIs while onTysabri for 2 years were always negative for new lesions as well as negative for active old lesion activity…
    Stopped Tysabri, and started another medication.. Within 8 months a new lesion appeared on the MRI..And I just did not feel as good with the new Rx as opposed to Tysabri..

    After being off Tysabri for 14 months we (my team) has decided to go back on Tysabri.

    Question: Is there ANY research that shows that your body gets a RESET for a new time period to be on Tysabri after being off of it for more than a year?

    I love the stuff….

  2. Patricia Browne says:

    I was on tysarbi and went off of it because I tested positive for JC Virus my titer was considered high and that was just recent blood work. I have been off of the tysarbri for over 3 years. I want to know if I am still at risk for PML now that I am serum positive with a high titer even though I’ve stopped the drug? What information can you give me that is forthcoming. I’m tired of being stonewalled by everyone I ask. Did tysarbri cause this virus that was dormant to come out and put me at risk even though I’ve stopped the drug.

    • Shasha says:

      Tysarbri lowering the immune system may let a person catch Lyme/colds/flu etc easier. 3 years may help your body get back to normal.

      Far Infrared Sauna may help detox drugs/chemicals/bacteria/yeast/heavy metals out of a person.
      Gluten/dairy/soy/sugar/GMO may lower the immune system and nutrients absorbed in intestines. Not eating these and taking vitamins/good oils/minerals…LDN..detoxing may help the immune system and MS. LDN may help the immune system work righth and block hidden gluten. Zinc/fish oil/Vit D3/Vit C etc may help the immune system.

      Helps my immune system/MS be strong:
      No gluten/dairy/soy/sugar/GMO and vitamins/good oils, LDN and detoxing help me. Vit D3 5000IU, zinc 50mg if detoxing, 2000mg fish oil , 20000mg evening primrose oil. 2000 mg lecithin, Phosphatidylserine/DMAE, krill oil, CLA, Coenzyme Q10, Rhodiola, Mg citrate 400mg, Vit C, 5000mcg of biotin, Nature’s Plus- Source of life multiple, HCl and enzymes with meals, dairy free probiotic, Vit B12 methylcobalamin shot/spray/under the tongue kind/intrinsic factor kind, MTHF folate, coenyzme Q10, rhodiola, may help brain/body/thyroid/depression/immune system and more. Gluten is wheat/barley/rye..oats may act like gluten with avenin. GMO corn/soy/canola oil may hurt. Amour thyroid maybe needed since gluten may made antibodies to the thyroid. Coenzymated B vitamins far from synthetic kind make make me calm.

      Sunlight (helps the immune system and helps to heal the gut lining),exercise, organic food, good water..not tap water, cooking by scratch pure food….. no food in a box/bag/premade/label/restaurant which may help avoid hidden gluten. Certified gluten free food may have 20ppm of gluten…too much. Nuts not sold in the shell/meat basting/some spices may have hidden gluten and lotion/make up etc. One restaurant cooks special for me…rice/veg/tea/extra mushrooms (no meat since the woks may have MSG/gluten in them).

      EDTA/DMPS IV chelations from an Alternative doctor, 600mg of cilantro, organic sulfur, Now brand- Detox support, Far Infrared Sauna and more may help detox. Hair tests show good minerals and heavy metals. Heavy metals can block thyroid and other chemical reactions in the body/brain.

      LDN may help block hidden gluten/heal the gut lining and help the immune system, but the Celiac diet is still needed. 100% no hidden or microscopic gluten may help. Cutting back on gluten or cheating by eating gluten hurts the immune system. It may take 1 1/2 months to heal the gut lining after getting hidden gluten.

      Amour thyroid has some T3 and Calcitonin. Synthroid is only T4..may not convert to T3. Zn/Se/enough iron/strong probiotic may help convert T4 to T3 for thyroid.

      Alternative doctors/chiropractors/acupuncturists and more may help with health/vitamins etc.

      Longer version:

  3. Patricia Browne says:

    What happens if you seroconverted to JC virus with a high titer & have been off of Tysarbi for at least 3 years? Is the drug company following these patients? I’d like to know.

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