Study of Abiraterone Acetate in Subjects With Metastatic Castration Resistant Prostate Cancer

Study Overview
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Brief Summary
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Abiraterone acetate is an orally effective CYP17 inhibitor, which is metabolized into abiraterone in the body, and its inhibitory activity against CYP17 is 10-30 times that of ketoconazole. Clinical studies have shown that abiraterone acetate can significantly reduce the level of prostate specific antigen (PSA) in PCa patients, and help to reduce tumors, extending the lifespan of patients with advanced PCa for several years, and the toxicity is acceptable.

Official Title
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A Randomised, Double-Blind, Multicentre Phase Ⅲ Study to Evaluate Abiraterone Acetate Versus Placebo Combined With Prednisone in Subjects With Asymptomatic or Mild Symptoms Without Chemotherapy, Metastatic Castration Resistant Prostate Cancer.

Conditions
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Metastatic Castration Resistant Prostate Cancer

Intervention / Treatment
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* Drug: Abiraterone Acetate
* Drug: Placebo
* Drug: Prednisone


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - 1.18 years and older, Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1, Life expectancy ≥ 6 months. 2. Prostate cancer. 3. Serum testosterone <50 ng/dL (or 1.7 nmol/L). 4. Prostate cancer progression or lesion metastasis. 5. Restriction of antiandrogen therapy. 6. Restriction of Radiation therapy. 7. The treatment period of ketoconazole for prostate cancer was not exceed 7 days. 8. Has not used opioid analgesics and azole drugs within 4 weeks before the first dose. 9. Question 3 of the Concise Pain Questionnaire (BPI-SF) scored from 0-3 points. 10. Adequate laboratory indicators. 11. Must be able to swallow tablets. 12. No pregnant or breastfeeding women, and a negative pregnancy test. 13. Understood and signed an informed consent form. Exclusion Criteria: Prostate pathology results are neuroendocrine prostate cancer. Has received cytotoxic chemotherapy or biological therapy for metastatic castration resistant prostate cancer. Has contraindications to the use of prednisone. A chronic disease that exceeds the prednisone dose in the study. Uncontrolled high blood pressure. Active or symptomatic viral hepatitis or other chronic liver disease. Visceral metastasis or brain metastasis. Pituitary or adrenal dysfunction. Active autoimmune diseases require the use of hormone therapy. Clinically significant heart disease. Participated in other clinical trials within 4 weeks.

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
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Abiraterone acetate group<br>Subjects in this group administered 4 tablets abiraterone acetate once daily and 5mg prednisone twice daily, in 28-day cycle on fasting conditions. | Drug: Abiraterone Acetate<br>* Subjects administered 4 tablets abiraterone acetate twice daily in 28-day cycle.<br>Drug: Prednisone<br>* Subjects administered 5mg prednisone twice daily in 28-day cycle.<br>|
| Placebo Comparator: Placebo group<br>Subjects in this group administered 4 tablets abiraterone acetate blank analog tablet once daily and 5mg prednisone twice daily, in 28-day cycle on fasting conditions. | Drug: Placebo<br>* Subjects administered 4 tablets abiraterone acetate blank analog tablet twice daily in 28-day cycle.<br>Drug: Prednisone<br>* Subjects administered 5mg prednisone twice daily in 28-day cycle.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to PSA progression (TTPP） | The time interval between the administration of the drug and the progression of serum prostate specific antigen (PSA). | Baseline up to 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prostate specific antigen remission time | It was ≥50% lower than the baseline, and was confirmed as remission after re-testing after ≥4 weeks. | Baseline up to 24 months | 
| Objective Response Rate (ORR) | The percentage of participants with a best overall response defined as complete response (CR) or partial response (PR). | Baseline up to 24 months | 
| Eastern Cooperative Oncology Group (ECOG) | The ECOG scoring standard is an indicator of the general health status and tolerance to treatment from the patient's physical strength. ECOG physical status score standard from 0 to 5. Starting with the dose until the score increases from the baseline. | Baseline up to 24 months | 
| Overall Survival (OS) | Time from date of randomization to date of death due to any cause. | Baseline up to 24 months | 
| To pain progression time | Time from the start of medication to the progression of pain. | Baseline up to 24 months | 
| Quality of life assessment scale (FACT-P) | Functional Assessment of Cancer Therapy- Prostate Cancer (FACT-P) total score, Functional Assessment of Cancer Therapy- General (FACT-G) total score, trial outcome index, functional well-being, physical well-being, prostate cancer subscale, and Functional Assessment of Cancer Therapy (FACT) Advanced Prostate Symptom Index-6 (FAPSI-6). | Baseline up to 24 months | 
| Prostate specific antigen remission rate | The remission rate was defined as the proportion of remissions to the total number of people. | Baseline up to 24 months |