A Clinical Study on the Efficacy and Safety of Fasudil Hydrochloride Combined With Immunotherapy in the Treatment of Metastatic Castration-resistant Prostate Cancer

Inclusion Criteria: 1. Age ≥ 18 years and \< 85 years; 2. Patients who have failed at least one chemotherapy regimen containing docetaxel and one standard novel endocrine therapy; 3. Diagnosed with CRPC, defined as: after continuous castration therapy, the castration level of testosterone is \< 50 ng/ml; disease progression within 12 weeks before enrollment: PSA levels increase consecutively for 3 times at intervals of 1 week, and serum PSA ≥ 2 ng/ml; evaluated as soft tissue progression according to RECIST criteria, or ≥ 2 new lesions on bone scan; 4. Imaging evidence indicates bone metastatic disease and/or measurable non-bone metastatic disease (lymph nodes or internal organs); Expected survival period ≥ 3 months; All patients voluntarily signed the informed consent form and were able to cooperate with treatment and follow-up; Exclusion Criteria: 1. Severe cardiovascular and cerebrovascular diseases; 2. Abnormal liver function: Total bilirubin in blood is less than 1.5 times the upper limit of normal value, and the ratio of blood ALT to AST is less than 2 times the upper limit of normal value; 3. Abnormal kidney function: Serum creatinine is less than 1.5 mg/dl or the creatinine clearance rate is greater than or equal to 60 cc/min; 4. Those allergic to the used drugs; 5. Those with tumors in other parts; 6. Abnormal thyroid function: Blood FT4 and/or TT4 levels are higher or lower than the normal value (normal blood FT4 level is 9-25 pmol/L (0.7-1.9 ng/dl), normal blood TT4 level is 64-154 nmol/L (5-12 ug/dl)); 7. Cortisol deficiency: Serum cortisol at 8 a.m. is less than 140 nmol/L (5 ug/dL).