For treating MS, the usual dosage of Tysabri is 300 milligrams (mg) per dose. You’ll receive one dose every 4 weeks. Note: In addition to treating MS, Tysabri has other uses. Keep in mind that ...

Biogen’s hopes that one of its established multiple sclerosis drugs might also help stroke sufferers have been dashed. Natalizumab – best known as MS drug Tysabri - failed to show any benefits ...