** Shares of Sarepta Therapeutics SRPT.O fall 18.7% to $10.83

** Sarepta would have to conduct new studies to demonstrate the safety of its Duchenne muscular dystrophy therapy, Elevidys, Endpoints News reports, citing a senior FDA official

** "We are looking at all the tools we have" - HHS spokesperson

** Sarepta did not immediately respond to a Reuters request for comment

** Including session's moves, stock down 91.2% YTD

(Reporting by Kamal Choudhury in Bengaluru)

((Kamal.Choudhury@thomsonreuters.com;))