To evaluate the efficacy and safety of rezvilutamide in combination with androgen deprivation therapy(ADT) and standard salvage radiation therapy(SRT) or rezvilutamide in combination with ADT in prostate cancer patients with biochemical recurrence of prostate-specific antigen(PSA) persistence after radical prostatectomy(RP).

Main Inclusion Criteria:

1. Age ≥ 40 years, male.

2. Patients with histologically-confirmed diagnosis of prostate adenocarcinoma.

3. pathologically node-negative (pN0) or pathologically node cannot be assessed (pNx);

4. Patients with PSA < 0.1ng/ml within 8 weeks after radical prostatectomy (RP) and maintained for at least 6 months;

5. Biochemical recurrence (two consecutive rises in PSA with absolute values > 0.2ng/ml, the time interval ≥ 2 weeks apart ) and no local recurrence or distant metastatic lesions on conventional imaging (bone scan and CT/MRI scan);

6. Eastern Cooperative Oncology Group (ECOG) performance status score of 0 to 1;

7. Estimated life expectancy >10 year;

8. Adequate laboratory parameters

   • Absolute Neutrophil Count (ANC) ≥ 1.5 x 10^9/L
   • Platelet count (PLT) ≥ 100 x 10^9/L
   • Haemoglobin (Hb) ≥ 90 g/L
   • Serum creatinine (Cr) ≤ 1.5 x upper limit of normal(ULN) or creatinine clearance > 50 ml/min.
   • Total bilirubin (TBIL) ≤ 1.5 x ULN.
   • Glutamic oxaloacetic transaminase (AST/SGOT) or glutamic alanine transaminase (ALT/SGPT) levels ≤ 2.5 x ULN.
   • International normalised ratio (INR) ≤1.5, prothrombin time (PT) and activated partial thromboplastin time (APTT)≤1.5 x ULN .
   • Left ventricular ejection fraction (LVEF) ≥ 50%.

9. Patients able to comply with the protocol. Arm 1 subjects are proposed to receive salvage radiation therapy, while arm 2 subjects are not suitable for or refuse radiation therapy.

10. Signed informed consent.

Main Exclusion Criteria:

1. Prior hormonal therapy (antiandrogens or gonadotropin releasing hormone) or prior radiotherapy to pelvic .

2. Postoperative biochemical recurrence with PSA > 2 ng/ml.

3. Postoperative pathology containing neuro-endocrine differentiation or small cell features.

4. Prior malignancy other than prostate cancer in the past three years.

5. History of any of the following:

   • Seizure or known condition that may pre-dispose to seizure
   • Severe or unstable angina, myocardial infarction, symptomatic congestive heart failure, arterial or venous thromboembolic events (eg, pulmonary embolism, cerebrovascular accident including transient ischemic attacks), or clinically significant ventricular arrhythmias within 6 months prior to entry.
   • Active infection (eg, human immunodeficiency virus [HIV] or viral hepatitis)

6. Any other serious or uncontrolled illness which in the opinion of the investigator makes it undesirable for the patient to enter the trial.