The FDA's statement follows a May 1997 disapproval of Myotrophin by an agency subcommittee. An April 9 hearing on the subcommittee's recommendation was canceled.
Treatment is mostly supportive.
Jason Rubin, a spokesman for Cephalon, said the FDA asked only for information from ongoing studies of the drug, including one in Japan. He said the agency did not ask the drug companies to conduct any new trials. An FDA committee last year raised questions about Myotrophin's safety and effectiveness. In a large European trial of the medication, there were more deaths in Myotrophin-treated patients than in patients not taking the drug. In a similar trial in North America, Myotrophin-treated patients showed a slower progression of disease than untreated patients.