- Arm 2 Prostate cancer patients with intial response to second generation anti-hormonal therapy (examples: abiraterone, enzalutamide, TAK 700), but later relapsed. Disease relapse would be defined as progressive disease at the time of entry demonstrated either by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 (measurable disease) or by two subsequently increasing Prostate-specific antigen (PSA) values obtained at least one week apart. If clinically meaningful benefits have been identified in a non-mCRPC patient population during the escalation phase, a potential third expansion arm may be considered.