...The therapy in question is Tysabri, and for many MS patients it appears to halt progression of the degenerative neurological disorder. But a year ago... corporate partners Biogen and Elan "voluntarily" withdrew their drug because of FDA pressure and litigation fear after two patients developed a rare brain infection. That infection might have been linked to Tysabri, since the drug works by suppressing parts of the immune system. But these patients also had other immuno-suppressive therapies, and in any case the MS patients were almost all willing to run the risk.... But shortly before the deadline, the FDA announced it...