WASHINGTON/NEW YORK (Reuters) – A U.S. congressional committee has demanded that former drug executive Martin Shkreli appear at a hearing on drug prices to testify about his former company’s decision to raise the price of a lifesaving medicine by more than 5,000 percent, congressional aides said on Wednesday. Shkreli, who is separately facing federal criminal charges that he defrauded investors, has been served with a subpoena to appear on Jan. 26 before the U.S. House of Representatives’ Committee on Oversight and Government Reform, the aides said.