3 Small-Cap Biotech Stocks With Big Catalysts in May

May's going to be a big month for a handful of small-cap biotechs and the Food and Drug Administration. Achaogen Inc. (NASDAQ:AKAO), Akcea Therapeutics Inc. (NASDAQ:AKCA), and Portola Pharmacuticals Inc. (NASDAQ:PTLA) are expecting important approval decisions from the FDA and success for any of these companies is far from guaranteed.