This study aims to compare the efficacy and safety of rezvilutamide with enzalutamide in the treatment of patients with low-volume metastatic hormone sensitive prostate cancer.

Inclusion Criteria:

1. Voluntarily participates in this clinical trial, with an understanding of the study procedures and signed informed consent;
2. Age ≥ 18 years;
3. Histologically or cytologically confirmed prostate adenocarcinoma without evidence of neuroendocrine differentiation or small cell features;
4. Metastatic hormone sensitive prostate cancer;
5. ECOG PS: 0-1;
6. Planned to receive and maintain ADT during the study period;
7. Adequate hepatic, renal, heart, and hematological functions;
8. Determined by the investigator to be able to comply with the study protocol;
9. Fertile subjects must use effective contraception or abstain from sexual activity and sperm donation until 3 months after last exposure to rezvilutamide or enzalutamide. Subjects must use condoms plus an additional effective contraceptive method during sexual activity with a fertile female partner throughout treatment and for 3 months post-treatment.

Exclusion Criteria:

1. Prior treatment with ADT, chemotherapy, surgery, external-beam radiotherapy, brachytherapy, radiopharmaceuticals, or investigational local therapy for metastatic prostate cancer, except as specifically allowed by the protocol;
2. Previous use of second-generation androgen receptor antagonists, ketoconazole, abiraterone acetate, or other investigational drugs inhibiting androgen synthesis for prostate cancer treatment; or plans to use any second-generation androgen receptor antagonist other than the study drug during the study treatment period;
3. Total PSA has decreased to undetectable levels at baseline;
4. Have participated in an interventional clinical trial or been treated with the following drugs in the past 4 weeks before randomization: 5-alpha reductase inhibitors, estrogen, progestin, and herbal products known to decrease PSA levels;
5. Planned to initiate any other anti-tumor therapies during the study;
6. Known history of hypersensitivity to rezvilutamide, enzalutamide, or any of their components;
7. Unable to swallow, chronic diarrhea or intestinal obstruction, or the presence of a variety of other factors that affect drug use and absorption;
8. History of seizure or certain conditions that may predispose to seizure;
9. Presence of clinically significant cardiovascular diseases within 6 months prior to randomization;
10. Any other malignancy within 5 years prior to randomization (except as specifically allowed by the protocol);
11. Active HBV or HCV infection;
12. History of immunodeficiency (including HIV-positive status, other acquired or congenital immunodeficiency disorders) or organ transplantation;
13. Any concomitant condition that, in the opinion of the investigator, would seriously jeopardize patient safety, confound study findings, or compromise the patient's ability to complete the study (e.g., hypertension inadequately controlled despite medication, severe diabetes, neurologic or psychiatric disorders, etc.) or any other circumstance.