A man with prostate cancer has died after receiving a second dose of Sophiris Bio Inc.'s topsalysin during a trial testing the inactivated pore-forming protein therapy. Investigators are now holding off on administering second doses to two additional patients as they seek further details of the death. Meanwhile, company shares (NASDAQ:SPHS) fell 40.3 percent to $2.24 on Monday, amid initial uncertainty about how soon the cause of the death would become clear.