• Known additional malignancy that is progressing or has required active treatment within the past 3 years (Patients with basal cell carcinoma of the skin, squamous cell carcinoma of the skin, or carcinoma in situ, excluding carcinoma in situ of the bladder, that have undergone potentially curative therapy are not excluded).

• Patients who have received chemotherapy, biological therapy, or immunotherapy for prostate cancer within 4 weeks from baseline (6 weeks in the case of nitrosoureas or mitomycin).

• Any prior treatment with taxane chemotherapy for mCRPC.

• Patients with history of allogeneic stem cell transplantation (alloSCT), or solid organ transplantation.

• Patients who have received high-dose chemotherapy requiring hematopoietic stem cell treatment, within 2 years from baseline.

• Patients who have previously received PSMA-targeted treatment (e.g., radiotherapy, immunotherapy, or antibody-drug conjugate) or those treated with radiopharmaceuticals such as radium-223 within 6 months from baseline.

• Patients who have previously received radiotherapy (RT) to the lung > 30 Gy within 6 months of the first dose.

• Prior exposure to any anti-programmed cell death protein 1(PD-1), anti-programmed death ligand 1/2 (PD-L1/L2), or anti- cytotoxic T lymphocyte antigen-4 (CTLA-4) antibody, or any other agent specifically targeting T cell co-stimulation or immune checkpoint pathways.

• Diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy (in dosing exceeding 10 mg daily of prednisone equivalent) or any other form of immunosuppressive therapy within 7 days prior the first dose of study intervention.

• Known active central nervous system (CNS) metastases and/or carcinomatous meningitis. Patients with previously treated brain metastases may enroll if they are radiologically stable (i.e., without evidence of progression) for at least 4 weeks, as confirmed by repeat imaging during the study screening. They must also be clinically stable and must not have required steroid treatment for at least 4 weeks before receiving the first dose of the study intervention.

• Patients with the following medical history or history of surgery/procedures:

  • Deep vein thrombosis (DVT) or pulmonary embolism (PE) within 1 year from baseline.
  • Cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infection within 6 months from baseline.
  • Acute coronary syndrome (unstable angina or myocardial infarction) within 6 months from baseline.
  • Major cerebrovascular disease, such as stroke, within 6 months from baseline.
  • General anesthesia or major surgery requiring respiratory assistance within 4 weeks from baseline (video-assisted thoracoscopic surgery or open-and-closed (ONC) surgery allowed within 2 weeks).
  • Active autoimmune disease that has required systemic treatment in past 2 years except replacement therapy (e.g., thyroxine, insulin, or physiologic corticosteroid).
  • History of (noninfectious) pneumonitis/interstitial lung disease that required steroids or has current pneumonitis/interstitial lung disease.

• Patients with the following conditions:

Class III or IV heart failure according to the New York Heart Association (NYHA) classification.

• Uncontrolled hypertension (systolic blood pressure (SBP) > 160 mm Hg or diastolic blood pressure (DBP) > 90 mm Hg).

• Clinically significant cardiovascular abnormalities as determined by the investigator (e.g., Left ventricular ejection fraction (LVEF) < 50%, clinically significant heart wall abnormalities, myocardial injury or QT interval corrected by Fridericia's formula (QTcF) > 450 msec for males or > 460 msec for females).

• Uncontrolled cardiac arrhythmia.

• Known positive human immunodeficiency virus (HIV) test or other uncontrolled active infectious diseases (e.g., Hepatitis B/C).

• Myelodysplastic syndrome (MDS).

• Clinically significant urinary obstruction or hydronephrosis that may affect renal function as determined by the investigator.

  • Patients receiving nephrotoxic drugs (e.g., aminoglycosides).
  • Patients with severe claustrophobia not controlled by anxiolytics.
  • Patients with hypersensitivity to any components of the investigational product (IP)s.
  • Patients unwilling to use appropriate contraceptive methods or abstain from intercourse during the clinical trial and for at least 4 months after discontinuation of the IPs if the patient's partner is capable of childbearing, or who do not agree to refrain from sperm donation during this period.
  • Patients who have received other IPs or undergone procedures involving investigational medical devices within 4 weeks from baseline.
  • Any other conditions deemed by the investigator as making the patient ineligible for clinical trial participation.