Biomarker development trial of satraplatin in patients with metastatic castrate-resistant prostate cancer.

170 Background: While satraplatin, a fourth generation oral platinum analogue, failed to improve overall survival (OS) in an unselected metastatic castrate-resistant prostate cancer (mCRPC) population (Sternberg, JCO 2009), anti-tumor activity was demonstrated, suggesting a “platinum-sensitive” subset of patients. Predictive biomarkers may not only select patients most likely to benefit from novel “targeted” therapies but also from standard (even discarded) cytotoxic agents. Development of predictive biomarkers in mCRPC is hampered by the fact that PC is associated with a long natural history and evolving genetic changes, highlighting the need for immediate pre-treatment metastatic tissue samples for biomarker development. In this trial, we sought to determine the feasibility of obtaining metastatic biopsies in patients with mCRPC treated with satraplatin. Methods: Docetaxel-refractory mCRPC patients underwent image-guided biopsy of metastatic lesions prior to treatment with satraplatin 80 mg/m2 PO on day...