BUZZ-Medivation: Cancer therapy not as safe as AstraZeneca's

** Drug developer's shares down 2 pct at $108.97premarket

** Says its prostate cancer therapy Xtandi was not as safeas AstraZeneca Plc's treatment Casodex in a mid-stagestudy

** Says 31 pct patients given Xtandi had serious adversereactions compared with 23.3 pct patients who were given Casodex

** Says Xtandi increased the time patients survived withoutprogression of the disease to 15.7 months, compared to 5.8months among Casodex patients

** Up to Wednesday's close, the stock more than doubledsince Xtandi was approved on Aug. 31 2012