News

European patient shows signs of PML

24 October 2014

The pharmaceutical sponsor of Tecfidera (BG-12), Biogen Idec, has this week reported one case of Progressive Multifocal Leukoencephalopathy (PML) in an individual currently being treated with Tecfidera in Europe.

Over 100 000 people around the world have been treated with Tecfidera, and this is the first reported case of PML in someone receiving this treatment. It is not yet clear the treatment history of this individual, and the extent to which Tecfidera has contributed.

Progressive multifocal leukoencephalopathy (PML) is a rare and potentially fatal viral brain infection characterised by progressive damage to the white matter of the brain. It is caused by the JC virus (JCV), which is present in about half of the general population, but only manifests in people whose immune system has been suppressed, including those on immunosuppressive medication. PML in people with MS is known to be a relatively rare safety risk of natalizumab treatment, with most cases of PML occurring after more than two years of natalizumab treatment.

This event should not be a cause for alarm in people currently taking this medication, and it is very important that people should not make any changes to their current medication regimen without first seeking medical advice. If you have any concerns about your current treatment plan, please speak to your neurologist.

Related News

Media Release

Early results show world-first adaptive trial in action for progressive MS

17 September 2026

A potential treatment for progressive multiple sclerosis (MS) will continue in a world-first multi-arm, multi-stage adaptive trial after showing encouraging early signs, with recruitment set to expand across Australia.

MS News

Alpha lipoic acid shows promise in Stage 1 of Octopus trial in progressive MS

17 September 2026

Results from Stage 1 of the Octopus trial find one of the trial treatments, alpha lipoic acid, shows promise in progressive MS and will continue into trial Stage 2.

MS News

Women and MS: one of the disease’s biggest mysteries

9 September 2026

Why does MS affect women more often than men? How does female biology impact MS activity? Discover what recent research is revealing about risk, hormones, immunity and EBV.

Read More

Newsletter subscription

  • This field is for validation purposes and should be left unchanged.

European patient shows signs of PML