 Zacks Investment Research upgraded shares of CymaBay Therapeutics NASDAQ:CBAY from a hold rating to a buy rating in a research note issued to investors on Monday morning, Zacks.com reports. Zacks Investment Research currently has 4.50 target price on the biopharmaceutical companys stock. According to Zacks, CymaBay Therapeutics Inc. is a biopharmaceutical company. It is focused ... 