Inclusion Criteria:
* 1\. ≥40 years old, male;
* 2\. Postoperative pathology showed prostate adenocarcinoma;
* 3\. Postoperative pathological stage pN0 or pNx;
* 4\. PSA decline \< 0.1ng/ml within 8 weeks after radical prostate cancer surgery for at least 6 months
* 5\. Biochemical recurrence (PSA rose twice in a row, with an interval of ≥2 weeks and absolute value \> 0.2ng/ml), and traditional imaging (bone scan and CT/MRI scan) did not show local recurrence and distant metastasis.
* 6\. Have one or more of the following risk factors:
* Postoperative CAPRA-S score ≥6 points;
* The pathological score of radical surgery for prostate cancer was Gleason 8-10;
* The highest postoperative biochemical recurrence PSA \> 0.5ng/ml;
* Postoperative pathological stage PT3/T4;
* PSADT \< 10 months;
* 7\. ECOG status is 0-1;
* 8\. Life expectancy greater than 10 years;
* 9\. Adequate hematological and organ function tests within 4 weeks prior to the first study treatment, as defined below:
* Neutrophil count (ANC)≥1.5×10\^9/L (no granulocyte colony-stimulating factor for 2 weeks prior to cycle 1, day 1);
* Platelet count (PLT)≥100×10\^9/L (no transfusion within 2 weeks prior to day 1 of cycle 1);
* Hemoglobin (Hb) ≥90g/L
* Serum creatinine (Cr)≤1.5×ULN or creatinine clearance \> 50ml/min;
* Total bilirubin (BIL)≤1.5×ULN;
* Aspartate aminotransferase (AST/SGOT) or alanine aminotransferase (ALT/SGPT) level ≤2.5×ULN;
* International Standardized ratio (INR) ≤1.5, prothrombin time (PT) and activated partial thromboplastin time (APTT) ≤1.5×ULN;
* Left ventricular ejection fraction (LVEF) ≥50%;
* 10\. The subject is willing and understands to sign the informed consent and is able to comply with the agreement.
Exclusion Criteria:
* 1\. Previously received endocrine therapy for prostate cancer (including but not limited to goserrelin, levoprorelin, digarek, bicalutamide, abiraterone acetate, darotamine, apatamide, enzalutamide, etc.) or pelvic radiotherapy;
* 2\. Postoperative biochemical recurrence, but PSA more than 2 ng/ml;
* 3\. Postoperative pathology contains non-adenocarcinoma components, such as neuroendocrine differentiation or small cell features;
* 4\. Is currently participating in or has participated in an investigational drug study;
* 5\. Known or suspected allergy to reverumide and reverumide excipients;
* 6\. Inability to swallow, chronic diarrhea, intestinal obstruction, or other factors that affect drug use and absorption;
* 7\. Have a history of epilepsy, or a medical condition that can induce seizures within the 12 months prior to C1D1 (including a history of transient ischemic attacks, cerebral stroke, traumatic brain injury with disturbance of consciousness requiring hospitalization);
* 8\. Active heart disease in the 6 months prior to C1D1, including severe/unstable angina, myocardial infarction, symptomatic congestive heart failure, and medically treatable ventricular arrhythmias;
* 9\. Have had any other malignancies within the 3 years prior to C1D1 (except for carcinoma in situ that has been in complete remission and malignancies that the investigator determined to be slowly progressing);
* 10\. Granulocyte colony-stimulating factor was used for support 2 weeks before C1D1;
* 11\. Blood transfusion within 2 weeks before C1D1;
* 12\. Active HBV and HCV infected persons (HBV copy number ≥10\^4 copies /mL, HCV copy number ≥10\^3 copies /mL);
* 13\. A history of immunodeficiency (including HIV positive, other acquired, congenital immunodeficiency diseases) or a history of organ transplantation;
* 14\. Male subjects whose partner is a fertile woman refuse surgical sterilization or use of effective contraception during the trial period and for 3 months after the last dose of riverutamide.
* 15\. The investigator determines subjects who may affect the conduct of clinical studies, who may not be able to comply with the protocol or cooperate with the protocol, and who pose research risks.
