An organized set of primary and secondary sources covering clinical background, drug-safety signals, and patient-safety considerations.
A Closer Look at Tysabri exposure linked to Progressive Multifocal Leukoencephalopathy: mechanisms and evidence — detailed background and analysis.
Reference: MedlinePlus — Trusted Health Information
Authoritative source for clinical, regulatory, and public-health background reading.
Reference: Centers for Disease Control and Prevention (CDC)
Authoritative source for clinical, regulatory, and public-health background reading.