(UroToday.com) Further therapies to improve patient outcomes in metastatic castration-resistant prostate cancer (mCRPC) are required as resistance to currently approved therapies invariably develops. Immunotherapy responses have been limited in mCRPC. Bispecific T-cell engagers are a novel approach to tumor immunotherapy (blinatumomab being the only currently approved BiTE therapy) which are targeted towards a tumor antigen as well as T-cells (via anti-CD3) to induce activation of the patient’s own T-cells to promote cytokine release and tumor killing.