GTx shares blitzed by FDA's toremifene rejection

Shares of GTx (GTXI) tumbled 34 percent in premarket trading as investors digested the sour news that the FDA is demanding data from a second late-stage trial of its bone loss drug before it makes a final ruling.

GTx is responding by asking for a meeting with regulators on toremifene (Acapodene), a therapy designed to treat bone loss triggered by hormone treatment in prostate cancer patients. The FDA's complete response letter, though, spelled out its demands for a new trial to gather hard data on the safety and efficacy of toremifene as well as data showing that the drug does not have a "detrimental effect on either time-to-disease progression or overall survival."

GHTx recently posted positive mid-stage cancer data. And in a recent Radar Report for FierceBiotech, Leerink Swann's Howard Liang noted GTx's pioneering "use of a selective estrogen receptor modulator (SERM) for prostate cancer prevention and for bone loss associated with standard prostate cancer treatment known as androgen deprivation therapy or ADT." But Acapodene has had trouble in the clinic, he added, which had significantly raised the risk of a regulatory rejection.  

- check out GTx's release