A Study of Androgen Receptor (AR) Antagonist Apalutamide in Chinese Participants With Metastatic Castration-Resistant Prostate Cancer

Study Overview
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Brief Summary
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The purpose of this study is to evaluate pharmacokinetics (PK) following a single dose and multiple dose treatment and the safety of apalutamide in Chinese participants with metastatic castration resistant prostate cancer (mCRPC) at dose of 240 milligram (mg).

Official Title
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A Phase 1 Study of Androgen Receptor (AR) Antagonist Apalutamide in Chinese Subjects With Metastatic Castration-Resistant Prostate Cancer

Conditions
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Prostatic Neoplasms

Intervention / Treatment
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* Drug: Apalutamide


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to (<=) 2 Histologically or cytologically confirmed adenocarcinoma of the prostate without neuroendocrine differentiation or small cell features Metastatic disease as documented by bone scan or metastatic lesions by computed tomography or magnetic resonance imaging scans (visceral or lymph node disease). Lymph nodes in the pelvis must measure at least 1.5 centimeter in a short axis to be considered target lesion according to the modified Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 based on the Prostate Cancer Working Group 2 (PCWG2) criteria Castration-resistant prostate cancer (PC) demonstrated during continuous androgen deprivation therapy (ADT), defined as 3 rises of prostate-specific antigen (PSA), at least 1 week apart, with the last PSA greater than or equal to (>=) 2 nanogram per milliliter (ng/mL) Prior hormonal interventions (including 1st generation antiandrogens [flutamide, bicalutamide, nilutamide], steroids, estrogens, finasteride, dutasteride) for PC are allowed. These therapies, except for gonadotropin releasing hormone analogs (GnRH) analogs and prednisone/prednisolone, must have been discontinued for minimally 4 weeks (2 weeks only for flutamide, nilutamide, or finasteride) before first dose of study drug Exclusion Criteria: Known brain metastases Chemotherapy, or immunotherapy within 2 weeks or 5 half-lives of the drug prior to the first dose of study drug, whichever is longer, with a maximum of 4 weeks. Prior treatment with second-generation anti-androgens (example [eg], enzalutamide) Administration of an investigational therapeutic within 2 weeks or 5 half-lives of the drug prior to the first dose of study drug, whichever is longer, with a maximum of 4 weeks. And participant use radiopharmaceutical agents (eg, strontium-89) or investigational immunotherapy (eg, sipuleucel-T) within 12 weeks prior to the first dose of study drug Prior treatment with cytochrome 17 inhibitors (eg, abiraterone acetate, orteronel, galeterone, systemic ketoconazole)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Apalutamide<br>Participants will receive a single oral dose of apalutamide 240 milligram (mg) during pharmacokinetics (PK) Week Day 1 and will be monitored for one week (that is; PK Week) to assess PK and safety of drug. Subsequently, participants will further receive daily treatment of apalutamide from Cycle 1 Day 1 onwards until disease progression, withdrawal of consent, lost to follow-up, or the occurrence of unacceptable toxicity. Each treatment cycle consists of 28 days. After final analysis (FA), participants who are receiving apalutamide in the open-label treatment phase may continue receiving single oral dose apalutamide 240 mg once daily in a long-term extension (LTE) phase if they continue to derive benefit from treatment (based on investigator assessment). | Drug: Apalutamide<br>* The participants will receive apalutamide 240 mg once daily orally.<br>* Other names: JNJ-56021927;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma Concentration of Apalutamide | Plasma concentration of apalutamide will be reported. | Predose; postdose up to 168 hours (hrs) (Cycle1 Day 7), Cycle 2 (pre-dose; on Day 1 and 15 of cycle 2) and Cycle 3 (pre-dose; up to 24 hrs post-dose). Each cycle is of 28 days | 
| Number of Participants with Adverse Events | An adverse event is any untoward medical event that occurs in a participant administered an investigational product, and it does not necessarily indicate only events with clear causal relationship with the relevant investigational product. | Up to 30 days of last study treatment (approximately 18 months) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline in Serum Prostate Specific Antigen (PSA) at Weeks 4 and 12 | Change from baseline in serum PSA levels will be determined. | Baseline, at Weeks 4 and 12 or earlier for those who discontinue therapy (up to approximately 4 months). | 
| Maximal Decline in Prostate Specific Antigen | Maximal decline in PSA levels will be determined. | Up to 30 days of last study treatment (approximately 18 months) |