Citi analyst Yigal Nochomovitz sees a favorable risk/reward on shares of Portola Pharmaceuticals into the May 4 FDA action date for AndexXa. With FDA approval, the stock could nearly double, Nochomovitz tells investors in a research note. His price target is $58, which reflects 90% upside from current share levels. If AndexXa fails to gain FDA approval or is again delayed, the stock is likely worth around $24 per share after removing U.S. AndexXa sales, or 20% downside from current levels. Nochomovitz thinks FDA approval of AndexXa is "more likely than not." The analyst keeps a Buy rating on Portola Pharmaceuticals.