This page collects vetted references on medical safety, regulatory guidance, and clinical background for anyone researching this topic.
Does Tysabri cause Progressive Multifocal Leukoencephalopathy Resource Guide
A focused look at the background, context, and key sources on this subject.
Reference: World Health Organization (WHO)
Authoritative source for clinical, regulatory, and public-health background reading.
Reference: National Institutes of Health (NIH)
Authoritative source for clinical, regulatory, and public-health background reading.