CHICAGO -- A representative from pharmaceutical company Sarepta -- manufacturer of the controversial Duchenne muscular dystrophy drug Exondys 51 -- touted FDA's use of regulatory flexibility to approve Exondys 51, saying the approach has been frequently used for oncology drugs and could be a boon for the rare disease space. But one legal expert urged caution, saying FDA needs to ensure the validity of the science as it heads into implementing the 21 st Century Cures Act, which will facilitate...