All DMT have Side-Effects

In light of the Teva’s challenge to Biogen’s BG-12, what next? Genzymne’s Lemtrada; if we are talking safety?

However, I would like to point out that when you move from low efficacy first-line drugs to much higher-efficacy drugs that globally inhibit immune function, then we should be expecting consequences of this, because this is the biology. 

This will include 
  • Increased risk of Cancers 
  • Increased Risk of Infections 

This is because, this is what the immune system does. It protects you from infections and the development of tumours. A very troubling infection is caused by JC virus that leads to PML, as we have no drug to deal with it and its consequences can be fatal. So if you keep your immune system low then this is a possibility.

This is a real problem with Tysabri, but has been shown to occur following B cell depletion with rituximab etc. There are reported cases of PML with Fumaderm, which contains the active ingredient in BG-12.

  Slide by Dr. Tim Vollmer

This drug can cause leucopaenia (depletion of white blood cells) and with Fumaderm there has been reported cases of Kaposi’s sarcoma and PML, which are signs of chronic leucopaenia. 

As all drugs induce side-effects it is the risk-benefit answer that we need to consider. The safety of BG-12, will become more evidence as more people take it. This will happen when it gets licensed.

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  • Tony raises a good question. I've been on Tysabri for over 4 years, going onto 5. Other than PML, is there any other risks, such as cancer, that I should be concerned about? Thanks.

  • I wonder if anyone keeps track of this? I guess Biogen is not incentivised to.

    Here is a survey idea to medical professionals around the world that will be very use full….
    After all, some have been on Tysavri for more than 10ys now ! (since the clinical trials participations)….

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