(UroToday.com) The American Urologic Association (AUA) annual meeting included a late-breaking abstract session with a presentation by Dr. Michel Pavic discussing results of the AB12003 trial assessing masitinib plus docetaxel as first-line treatment of metastatic castration-resistant prostate cancer (mCRPC). Masitinib is an oral, small molecule drug that targets mast cell and macrophage activity. These innate immune cells are critical components of the tumor microenvironment and are associated with prostate cancer progression. Previously, a small trial (AB07004) showed that masitinib plus docetaxel slowed progression in patients with mCRPC.