A phase II, open-label, multi-arm study of TAS-115 for castration-resistant prostate cancer patients with bone metastases.

164Background: TAS-115, a novel multi-kinase (eg, MET, VEGFR) inhibitor has also shown to inhibits Feline McDonough Sarcoma oncogene (FMS) kinase, Anti-tumor activity against bone metastases was observed in the preclinical and phase1 study. In this phase 2 study, the efficacy and safety of TAS-115 were evaluated in castration-resistant prostate cancer (CRPC) patients (pts) with bone metastases. Methods: This was a phase 2, open-label, multi-arm study for CRPC pts with bone metastases to evaluate the clinical anti-tumor activity of TAS-115. Pts who had visceral metastases were ineligible for this study. TAS-115 was given orally, once daily, and schedule of 5 days on/2 days off each week was repeated. This study had 2 cohorts (A and B). In cohort A, TAS-115 ranging from 200 to 400 mg/day with abiraterone acetate was given to pts prior to docetaxel. In cohort B, CRPC pts who had symptomatic bone metastases, post or unfit to docetaxel, were randomized in a 1:1 to 400 or 600 mg/day of TAS-115. The primary endp...