The FDA has removed the hold on clinical trial dosing of Tysabri in multiple sclerosis (MS) in the U.S. Biogen Idec and Elan Corp. expect to begin an open label, multi-center safety extension study of Tysabri monotherapy in the U.S. and internationally in the coming weeks. Patients who previously participated in the Phase III MS program are eligible for entry. Biogen Idec and Elan had previously voluntarily suspended Tysabri from the U.S. market and all ongoing clinical trials based on repo...