i have a feeling (which isn't worth much, facts are!) that they had reports come to them. people can report adverse drug events directly to the fda, or to the drug company, which is then required to disclose to the fda. the fact that the fda mentioned permenant disability (according to the article) makes me think they must have gotten some specific reports, but i'd say anyone who wants more details should call the fda. i don't think they associated the adverse outcome with never starting another one again - just the act of stopping gilenya. not sure if it matters if they start another drug or not. but YES more details would be helpful. article above says it's rare, but how rare? #s would be nice. :-)