A Study of TAK-385 in Hormone Treatment-naïve Participants With Prostate Cancer
Condition: Hormone Treatment-naïve Participants With Prostate Cancer
MeSH terms: Prostatic Neoplasms
Intervention: TAK-385
Intervention description: TAK-385 Tablets.
Intervention MeSH terms: Relugolix
Phase: Phase 1
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Sequential Assignment
Masking: None (Open Label)
Enrollment: 43.0
Sex: Male
Minimum age: 20 Years
Healthy volunteers: No

Summary:

      The purpose of this study is to evaluate the tolerability and safety of TAK-385 in hormone
      treatment-naïve participants with non-metastatic prostate cancer.
    

Eligibility criteria:

        Inclusion Criteria:

          1. Participants judged by the investigator to have the capacity to understand the study
             and follow the study rules.

          2. Participants whose written consent (signature or printed name and personal seal on
             informed consent form) can be obtained before any study procedures are performed.

          3. Japanese male participants 20 or more years of age at the time of informed consent.

          4. Participants who, if they have a female partner who could become pregnant, agree to
             practice appropriate means of contraception from the time of informed consent
             throughout the entire study treatment period and for 4 months after the last dose of
             study drug.

          5. Participants in stable medical condition, including the absence of acute exacerbations
             of chronic illnesses, serious infections, or major surgery within 4 weeks (28 days)
             prior to study treatment initiation.

          6. Participants with histologically or cytologically confirmed prostate cancer.

          7. Participants whose clinical diagnosis is T1-4 N0 M0, or Tx N0 M0 for participants who
             have undergone radical prostatectomy.

          8. Participants who are considered eligible for hormone therapy for prostate cancer.

          9. Participants who have not received hormone therapy (example, gonadotropin-releasing
             hormone [GnRH] agonist, GnRH antagonist, steroidal antiandrogen, non-steroidal
             androgen) for prostate cancer.

         10. Participants who have not undergone surgical castration.

         11. Participants with serum testosterone at screening greater than (>) 150 nanogram per
             deciliter (ng/dL).

         12. Participants meeting either of the following criteria for prostate-specific antigen
             (PSA) at screening. Untreated prostate cancer: PSA at screening > 4.0 nanogram per
             milliliter (ng/mL) Treated* prostate cancer: PSA at screening > 0.2 ng/mL.

               -  Participants who have undergone prostatectomy or either or both of high intensity
                  focused ultrasound therapy or radiotherapy (excluding 125I-brachytherapy) prior
                  to the start of this study.

         13. Eastern Cooperative Oncology Group (ECOG) Performance Status [17] of 0 or 1.

         14. Body mass index (BMI) at screening greater than or equal to (>=) 18.0 kilogram per
             square meter (kg/m^2).

        Exclusion Criteria:

          1. Participants exhibiting symptoms judged related to prostate cancer by the investigator
             (example, bone pain, pelvic pain, ureteral obstruction) who urgently require hormone
             therapy such as GnRH agonist, GnRH antagonist, or CAB/MAB therapy, chemotherapy, or
             radiotherapy.

          2. Participants who have received 5-alpha reductase inhibitors (except for participants
             who have been treated for male-pattern alopecias).

          3. Participants who have received chemotherapy for prostate cancer (including
             estramustine).

          4. Participants who have received 125I-brachytherapy.

          5. Participants who received radiotherapy (except for 125I-brachytherapy) within 16 weeks
             (112 days) before study treatment initiation.

          6. Participants who underwent prostatectomy within 16 weeks (112 days before study
             treatment initiation.

          7. Treatment with any investigational compound within the 4 weeks (28 days) prior to the
             first dose of study drug or ongoing participation in another experimental trial
             related to the treatment of prostate cancer.

          8. Diagnosis or treatment for another systemic malignancy within 2 years before study
             treatment initiation, or who had received a diagnosis of another malignancy before
             that and have evidence of residual disease. Participants with non-melanoma skin cancer
             or carcinoma in situ who have undergone complete resection will not be excluded from
             the study.

          9. Participants taking drugs with moderate to strong cytochrome P450 3A4 (CYP3A4)
             inhibitory or inducing effects, or any medications, supplements, or food products with
             P-glycoprotein (P-gp) inhibitory effects, in the 2 weeks (14 days) prior to study
             treatment initiation.

         10. Participants who have received TAK-385 in a past clinical study.

         11. Participants for whom it would be difficult to collect blood from a peripheral vein.

         12. Participants with uncontrolled and clinically significant nervous, circulatory,
             pulmonary, hepatic, renal, metabolic, gastrointestinal, urogenital, or endocrine
             disorders, or other abnormalities (except for the targeted disease) that could affect
             study participation or the study results. Also, participants meeting any of criteria a
             through c below.

             A. Participants with uncontrolled diabetes (Hemoglobin A1c [HbA1C] > 8 percent [%] at
             screening). However, participants whose HbA1c is brought under control with diabetes
             medications may be rescreened.

             B. Participants with uncontrolled hypertension (systolic blood pressure > 150
             millimeter of mercury (mmHg) and diastolic blood pressure > 90 mmHg at 2 separate
             measurements taken no more than 60 minutes apart at screening). Participants whose
             blood pressure is brought under control by antihypertensive medication may be
             rescreened.

             C. Participants with myocardial infarction, unstable symptomatic ischemic heart
             disease, arrhythmias of common terminology criteria for adverse events (CTCAE) Grade >
             2, thromboembolism (deep vein thrombosis, pulmonary embolism, or symptomatic
             cerebrovascular events), or other heart diseases (example, pericardial effusion,
             restrictive cardiomyopathy). However, chronic stable atrial fibrillation controlled by
             stable anticoagulant therapy will be allowed.

         13. Participants with bilateral hydronephrosis or bladder neck outlet obstruction.

         14. Known hypersensitivity to TAK-385, TAK-385 excipients, or gonadotropin-releasing
             hormone (GnRH) antagonists.

         15. Participants with a past history of gastrointestinal tract treatments (including
             gastrectomy) or gastrointestinal disease that could affect the drug absorption or
             tolerability (malabsorption, esophageal reflux, peptic ulcer, erosive esophagitis).

         16. Participants positive for hepatitis B surface antigens (HBsAg), hepatitis C antibodies
             (HCV), human immunodeficiency virus (HIV) antibodies, or serologic test for syphilis,
             or with life-threatening disease other than cancer, at screening.

         17. Clinically relevant electrocardiogram (ECG) abnormalities, or the following ECG
             abnormalities, at screening.

               -  Q-wave infarction, unless identified 6 or more months prior to TAK-385 treatment
                  initiation.

               -  QTcF interval > 450 millisecond (msec) (when calculating the QTc interval,
                  Fridericia's equation [QT/RR0.33] will be used).

         18. Participants with congenital QT prolongation.

         19. Current use of Class 1A or Class 3 antiarrhythmic medications.

         20. New York Heart Association Class III or IV heart failure.

         21. Participants with clinical laboratory abnormalities suggesting clinically relevant
             underlying disease, or with any of the following abnormal results, at screening.

               -  Serum creatinine >= 2.0 mg/dL.

               -  Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) >= 1.5*upper
                  limit of normal (ULN) for the study site.

               -  Total bilirubin >= 2*ULN for the study site.

               -  Neutrophil count less than (<) 1,500 per cubic millimeter (/mm^3), platelet count
                  < 100,000 per microliter (/mcL), hemoglobin < 10.0 g/dL.

               -  Results of heart-related tests (creatine kinase MB [CK-MB] and cardiac troponin
                  T) exceeding the study sites reference value.

         22. Participants found to have clinical problems on the basis of examination findings, ECG
             findings, or chest X-ray findings at screening.

         23. Participants considered unlikely by investigators to be able to follow the study
             protocol or considered ineligible for the study by investigators for other reasons.