MITO - X MITO among premarket losers December, 20 2019 09:12 AM Stealth BioTherapeutics Corp. Stealth BioTherapeutics (NASDAQ:MITO) -56% after elamipretide flunks late-stage PMM study.More news on: Stealth BioTherapeutics Corp, Valeritas Holdings, Inc., Abeona Therapeutics Inc., Stocks on the move, Read more ...