A Phase 3 Study of Deutenzalutamide in Patients With High-Risk BCR Prostate Cancer

This is a multicenter, randomized, double- blind, placebo-controlled Phase III trial to evaluate the efficacy and safety of Deutenzalutamide plus ADT versus placebo plus ADT in patients with high-risk biochemical recurrence (BCR) of prostate cancer after definitive therapy.

Inclusion Criteria: 1. Age 18 years or older men, be willing and able to provide informed consent. 2. Histologically or cytologically confirmed adenocarcinoma of the prostate at initial biopsy, without neuroendocrine differentiation, signet cell, or small cell features. 3. Prostate cancer initially treated by radical prostatectomy or radiotherapy (including brachytherapy) or both, with curative intent. Prostate cryoablation is not considered definitive therapy for this study, but its prior use is not exclusionary. 4. BCR prostate cancer, PSA doubling time (PSADT)≤9 months as calculated by the sponsor. 5. Screening PSA by the local laboratory as described in the protocol for patients who had radical prostatectomy (with or without radiotherapy) as primary treatment for prostate cancer and for patients who had radiotherapy only as primary treatment for prostate cancer . 6. Serum testosterone by the local laboratory ≥150 ng/dL (5.2 nmol/L) at screening. 7. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 at screening. 8. Estimated life expectancy of ≥12 months. 9. Able to swallow the study drug and comply with study requirements. 10. Has adequate organ function. 11. Must be willing to use reliable contraceptive measures (eg, condom) and refrain from sperm donation throughout the study and through 3 months after the last dose of study drug. Exclusion Criteria: 1. Prior or present evidence of distant metastatic disease as assessed by computed tomography (CT) or magnetic resonance imaging (MRI) for soft tissue disease and whole-body radionuclide bone scan for bone disease. Patients with soft tissue pelvic disease may be eligible if the short axis of the largest lymph node is \500 ms; 7. Hypotension as indicated by a minimum of 2 consecutive blood pressure measurements showing systolic blood pressure \160 mmHg or diastolic blood pressure \>100 mmHg at screening. 13. History of seizure or any condition that may predispose to seizure (eg, prior cortical stroke or significant brain trauma). History of loss of consciousness (unless of cardiac origin) or transient ischemic attack within 12 months before randomization. 14. Gastrointestinal disorder affecting drug absorption or swallowing. 15. History of allogeneic bone marrow transplantation or organ transplantation requiring continued medical treatment. 16. Known congenital or acquired immunodeficiency, active hepatitis, active tuberculosis, and other active infections. 17. Known hypersensitivity reaction to deutenzalutamide or any of capsule components (polyethylene glycol hydroxystearate, butylated hydroxyanisole, and butylated hydroxytoluene). 18. Contraindication to the use of androgen deprivation therapy (ADT). 19. In the investigator's opinion, the participant is unsuitable for participation in this study (eg, not consistent with the most beneficial treatment for the participant, participant compliance). 20. Ongoing drug or alcohol abuse as per investigator judgment. 21. Any concurrent disease, infection, or comorbid condition that interferes with the ability of the patient to participate in the study, which places the patient at undue risk, or complicates the interpretation of data, in the opinion of the investigator or medical monitor.