A Study to Evaluate the Safety, Pharmacokinetics, Pharmacodynamics, and Antitumor Activity of INV-9956 in Adult Patients With Advanced Metastatic Castration Resistant Prostate Cancer

This is a Phase 1 and Phase 2 study to evaluate the safety and antitumor activity of INV-9956 in adult patients with advanced metastatic Castration Resistant Prostate Cancer. The entire study consists of two parts: Phase 1 for dose escalation and Phase 2 for dose expansion. Phase 1 dose escalation of INV-9956 follows a real time monitored, PK/PD and safety guided scheme with a traditional 3+3 design for DLT assessment. Phase 2 aims to reassure the safety profile and better define efficacy. Phase 2 consists of up to 2 cohorts by different AR gene status: * Cohort A: AR mutant CRPC * Cohort B: AR wide-type CRPC (optional) Currently enrolling patients under Phase 2.