A Study of SHR2554 Alone or in Combination With SHR3680 in the Treatment of mCRPC

Inclusion Criteria:

1. Histologically or cytologically confirmed prostate cancer;
2. Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) of 0 or 1;
3. Radiographic evidence of metastasis;
4. Sustained therapy of luteinizing hormone-releasing hormone analogue（LHRHA）or received bilateral orchiectomy; patients who did not receive bilateral orchiectomy are willing to receive sustained therapy of LHRHA;
5. Evidence of prostate cancer progression under the sustained therapy of LHRHA or bilateral orchiectomy;
6. Adequate hepatic, renal, heart, and hematological functions;
7. Patients have given voluntary written informed consent before performance of any study-related procedure not part of normal medical care,with the understanding that consent may be withdrawn by the subject at any time without prejudice to future medical care.

Exclusion Criteria:

1. Have received any anti-tumor therapy in the past 4 weeks,including radiotherapy, chemotherapy, operation, targeted therapy, immunotherapy, and endocrinotherapy;
2. Planned to initiate any other anti-tumor therapies during the study;
3. Unable to swallow, chronic diarrhea and intestinal obstruction, or the presence of a variety of other factors that affect drug use and absorption;
4. Clinically significant cardiovascular diseases;
5. History of seizure or certain conditions that may predispose to seizure;
6. Severe concurrent disease and infection that, in the judgment of the investigator, would make the patient inappropriate for enrollment.