Possible JC Virus Vaccination Offers Important Implications for MS Treatment

Possible JC Virus Vaccination Offers Important Implications for MS Treatment

Two studies recently published in the journal Science Translational Medicine, revealed a possible new vaccine treatment for JC virus with important implications for multiple sclerosis (MS) treatment. The studies are entitled “JC polyomavirus mutants escape antibody-mediated neutralization” and “Broadly neutralizing human monoclonal JC polyomavirus VP1–specific antibodies as candidate therapeutics for progressive multifocal leukoencephalopathy.” The research was led by an international team of scientists at the National Cancer Institute in the United States, San Raffaele Scientific Institute in Italy, and University Hospital Zurich, University of Zurich, and Neurimmune Holding AG in Switzerland.

The JC virus is usually not harmful, unless the infected person has a weakened immune system, as is the case of MS patients under immunosuppressive medications. In these cases, the JC virus can opportunistically infect the brain and induce a rare, often fatal brain disease called progressive multifocal leukoencephalopathy (PML), which is characterized by inflammation and progressive damage of the white matter of the brain.

“In healthy people, the disease never breaks out as the immune system keeps it well under control. Once the immune system is compromised, however, such as in patients with tumors, leukemia, AIDS, autoimmune diseases and certain immunosuppressive treatments, the JC virus is able to alter its genetic information and infect the brain,” explained the co-author of both studies Dr. Roland Martin from the University of Zurich in a news release.

One well-known case is the use of the humanized monoclonal antibody Tysabri (natalizumab) as a therapy for MS, which has been associated with the development of PML. It is thought that while the antibody prevents immune cells from reaching the brain, it also blocks its immunosurveillance system. It is estimated that more than 560 MS patients in the world have developed PML, and of these, 20% died from the disease, as there is no treatment available for JC virus infection.

Now, researchers report that there is a possible vaccination approach to preventing PML, or, if a person’s brain is already infected, a treatment with virus-specific human antibodies.

In one of the studies, researchers found that antibodies in PML patients are often unable to recognize the JC virus strain that has infected the individual due to viral genetic mutations that make the virus “invisible” to the host’s immune system. In the second study, authors offer a solution, as they show that the use of broadly neutralizing antibodies obtained from a particular PML patient who recovered from the disease can be an effective therapeutic strategy for PML and JC virus infection.

The discovery of these specific antibodies allowed the development of a vaccine based on the coating protein of the JC virus. Using mouse models and 3 PML patients, researchers showed that vaccination triggers a very strong antibody immune response — a response so effective that patients were able to eliminate the JC virus from their brains.

“We made a major breakthrough,” concluded Dr. Martin. “We managed to isolate antibody-producing cells from a patient who survived PML and use them to produce neutralizing antibodies against the JC virus. These human antibodies have a major advantage: they recognize the most important mutants of the JC virus that can cause PML. They now make promising candidates for the development of a treatment for PML.”


  1. Steven Izard says:

    Yes, I tested positive for the JC Virus, and am currently taking infusions of Tysabri every 4 weeks. Last August would have been my one year for the drug, and I was wondering how much longer I could continue this medication without seriously jeopardizing my exposure to PML? I am going to see my Neurologist in January, and will discuss possibly going on Gylennia (Oral Drug), after Tysabri.

    • Denise Brown says:

      I was taken off Tysabri three years ago because I tested positive for the JC virus. I was then referred to take Gilenya. I don’t really feel that drug is working for me either. I can still walk but always tired a lot. I feel I was doing better one Tysabri. What do I do now? See doctor the end of the month.

  2. Patricia Silva, PhD says:

    Hello Steven and Denise, these are topics and options that vary from person-to-person, so only your doctor is eligible to discuss them with you and together decide on the best treatment option.

  3. debbie says:

    My mum was diagnosed in November 2015 with PML and there was no reason for her to get this virus. I am hoping someone can explain to me how you get this disease with no known cause. She was 66 and passed away December 22, 2015. She was relatively healthy up to this point

    • Sheila says:

      Can I please ask you a question I just went to a new neurologist and he did blood work and it shows I have a 1.53 postive for. Bcc
      The virus he didn’t say anything I went on line to see test results found should I worry about it
      Thank you

  4. Debbie says:

    I am hoping someone can explain to me how you get PML for no known reason. My mum was diagnosed November 2015 and passed away December 22 2015. Before this she was relatively healthy. Just trying to make sense of this horrible situation.

  5. Jess C says:

    I am 29 years old and live in Western Australia, I have been diagnosed with MS and have just received my 4th does of tysabri and just told that I am positive with the JCV with a count of 2.07 apparently I can stay on tysabri for a total time of 24 months but with then have to change medications now I have the fun of trying to find a medication to change to?

    • Emmie says:

      Hi Jess, I am 29 also from Tasmania. I tested positive for JC but not sure at what count. I have had only one tysabri infusion, and that’s the only treatment I’ve had. How are you going with it? I am in the same boat, I don’t want tysabri to work for me when I can only stay on it for 24 months. I currently have no problems, I am scared of the rebound effect once I stop and having to start a new drug that may not be as effective and end up worse than when I began. Have you talked to your doctors about it any more?

  6. Roxanne says:

    I was diagnosed with ms 12years ago and just recently was told that I have the JCV. I have had about 101 infusions of tysabri and have been doing wonderful with no problems and now I don’t know what is going to change with my treatment if anything. I still need to get my MRI and blood work done again to show me were my markers are at.

  7. Donna says:

    How close is the medical community on the development of the vaccine for JCV? Will it be coming out in 2016? My son just started talking tysabri with the hopes of getting the vaccine before he had a chance to develop JCV. Do you have a timeline when this will happen?

  8. TANYA HAGLER says:

    My husband and I are really “lucky.” He has Wegeners and I have MS. He takes rituxumab and I have taken tysabri. I tried tecfidera after tysabri. I was on it for about a year. It did not work well for me. Am looking at Lemtrada and Zinbryta. So far we are both JC neg, but who knows when it might change. I saw where PML is indicated with techfidera. How is that possible? Could it be that the patient (s) were previously on a mab and the PML just wasn’t seen until after the techfidera started? Looking forward to a JC vaccine!!

  9. Cas says:

    I have been on Gilenya for about 4 years. I just tested positive for the JVC virus. I had the symtoms of the virus. Cant take
    Shots so not sure what
    I will do. Im not incline to take anything that could lead me to get PML

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