Sophiris Bio has received a green light to begin dosing patients in a Phase 2b U.S. clinical trial of topsalysin (PRX302) for prostate cancer. The go-ahead was in the form of a Federal Drug Administration approval of a substance that Sophiris uses to dilute topsalysin, according to a press release. The therapy is for an enlarged prostate as well as cancer that has yet to spread from the prostate. The multi-center trial (NCT03081481) will eval