Sarepta Therapeutics gets stop work order from US defense dept

* Says the order related to Ebola contract

* Shares fall 6 pct in after-market trade

Aug 3 (Reuters) - Sarepta Therapeutics Inc, which gets a majority of its revenue from government drug research contracts, said the United States Department of Defense ordered it to stop work on the Ebola portion of a contract, citing funding constraints.

Sarepta's shares fell 6 percent to a low of $8.20 in after-market trade. They closed at $8.73 on the Nasdaq on Friday.

The stop-work order does not apply to the ongoing Marburg portion funded under the same hemorrhagic fever virus therapeutics contract, Sarepta said in a regulatory filing.

The stop-work order will remain in effect till Sept. 1, before which the DoD will either lift it, extend the stop-work period or end the Ebola portion of the contract.