A Study of Abiraterone Acetate Plus Prednisone in Patients With Metastatic Castration-Resistant Prostate Cancer Who Have Failed Docetaxel-Based Chemotherapy

Overall survival was defined as the time interval from the date of randomization to the date of death from any cause.

Percentage of participants who achieved PSA response (defined as >= 50% PSA decline from baseline) according to PSAWG criteria were reported. PSAWG criteria- Decline from baseline and reach response criteria: >= 50% increase over the nadir and the increase in the absolute-value by at least 5 ng/mL (or back to the baseline), which is confirmed by a second value 4 or more weeks later; Decline from baseline but not reach response criteria: >=25% increase over the nadir and the increase in the absolute-value by at least 5 ng/mL, which is confirmed by a second value 4 or more weeks later; and No decline from baseline: >=25% increase over the baseline and the increase in the absolute-value by at least 5 ng/mL, which is confirmed by a second value 4 or more weeks later.

ORR was defined as the percentage of participants with measurable disease at baseline achieving a complete response (CR) or partial response (PR) according to modified response evaluation criteria in solid tumors (RECIST) criteria. RECIST criteria for CR: disappearance of all target lesions and non-target lesions and normalization of tumor marker level. PR: At least a 30% decrease in the sum of the longest diameter (LD) of target lesions, taking as reference the baseline sum LD.

FACT-P assesses symptoms/problems related to prostate carcinoma and its treatment. It is a combination of the FACT- General + the Prostate Cancer Subscale (PCS) (Range 1-156, higher scores better). The FACT-General (FACT-G) is a 28 item Quality of Life (QOL) measure that provides a total score as well as subscale scores: Physical (0-28), Functional (0-28), Social (0-28), and Emotional (0-24) Well-being. The total range was between 1-108, higher scores better. Functional Assessment of Cancer Therapy-Treatment Outcome Index (FACT-TOI) is derived from the sum of the Physical Well-Being, Functional Well-Being, and Prostate Cancer subscale scores; a sensitive measure of patient-reported health (Range 1-104, higher scores better). PCS is a 12-item prostate cancer subscale that asks about symptoms and problems specific to prostate cancer (Range 0-48, higher scores better).

Time to Pain progression calculated as number of days from date of randomization to date of pain progression. Pain progression- worsening of pain due to metastatic bone disease defined as increase of >=30% in worst pain over past 24 hours on BPI-SF numeric rating scale at 2 consecutive evaluations 4 weeks apart without decrease in analgesic usage score (in 2 corresponding consecutive evaluation in analgesic usage score, if there is missing visit, use existing visit only) or increase in analgesic usage score >=30% at 2 consecutive evaluations 4 weeks apart. BPI-SF is 11-item questionnaire which includes 4 questions that assess pain intensity and 7 questions that assess impact of pain on daily functions. Total score (average of individual questions) ranges from 0=No pain to 10=Pain as bad as you can imagine; Higher scores= greater pain. Analgesic usage was scored on scale of 0 to 3 where 0=no analgesic, 1=non-opioid analgesics, 2=opioids for moderate pain and 3=opioids for severe pain.

Percentage of participants experiencing pain palliation were reported. A participant is responder if experienced >=30% reduction in Brief Pain Inventory - Short Form (BPI-SF) worst pain intensity score over 24 hours observed at 2 consecutive evaluations 4 weeks apart without any increase in analgesic usage score (best response). Analgesic usage was scored on a scale of 0 to 3 where 0=no analgesic, 1=non-opioid analgesics, 2=opioids for moderate pain and 3=opioids for severe pain. BPI-SF is 11-item self-reported questionnaire designed to assess severity and impact of pain on daily functions. It includes 4 questions that assess pain intensity (worst, least, average, right now) and 7 questions that assess impact of pain on daily functions (general activity, mood, walking ability, normal work, relations with other people, sleep, enjoyment of life). Total score (average of individual questions) ranges from 0=No pain to 10=Pain as bad as you can imagine; Higher scores indicate greater pain.

The Brief Fatigue Inventory (BFI) is a brief participant-reported questionnaire that measures the severity of fatigue based on the worst fatigue experienced during the past 24-hours. BFI has nine items. Three items ask patients to rate the severity of their fatigue at its "worst," "usual," and "now" during normal waking hours, with 0 being "no fatigue" and 10 being "fatigue as bad as you can imagine." Six items assess the amount that fatigue has interfered with different aspects of the patient's life during the past 24 hours. The interference items include general activity, mood, walking ability, normal work (includes both work outside the home and housework), relations with other people, and enjoyment of life. The interference items are measured on a 0-10 scale, with 0 being "does not interfere" and 10 being "completely interferes." BFI Total Score is the average of the nine items, ranging from 0 (no fatigue) to 10 (high fatigue).