A Safety and Efficacy Study of Abiraterone Acetate in Participants With Prostate Cancer Who Have Failed Hormone Therapy

The PSA response was measured according to PSA working group (PSAWG) criteria. All participants achieving a fall in PSA of greater than 50 percent from baseline, which has been confirmed by a second measurement at least 4 weeks after initial documentation, fulfill criteria for confirmed PSA response.

Number of participants with objective response based on assessment of confirmed complete response (CR) or confirmed partial response (PR) according to Response Evaluation Criteria in Solid Tumors (RECIST). Confirmed CR defined as disappearance of all target lesions. Confirmed PR defined as greater than or equal to 30 percent decrease in sum of the longest dimensions (LD) of the target lesions taking as a reference the baseline sum LD according to RECIST. Confirmed responses are those that persist on repeat imaging study greater than or equal to 4 weeks after initial documentation of response.

Duration of PSA response in participants on abiraterone acetate therapy was measured as the duration between PSA 50 percent decline date and PSA progression date as defined by the PSAWG criteria.

Number of participants with objective response based on assessment of confirmed CR or confirmed PR according to RECIST. Confirmed CR defined as disappearance of all target lesions. Confirmed PR defined as greater than or equal to 30 percent decrease in sum of the LD of the target lesions taking as a reference the baseline sum LD according to RECIST. Confirmed responses are those that persist on repeat imaging study greater than or equal to 4 weeks after initial documentation of response.

Disease progression was defined as greater than 25 percent increase in sum of longest diameter of target lesions compared to baseline.

Overall survival was the duration from enrollment to death. For participants who are alive, overall survival was censored at the last contact.

Concentration of testosterone in blood was measured in nanogram per deciliter (ng/dL).

An AE was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. An SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. Treatment-emergent are events between first dose of study drug and up to 28 days after last dose that were absent before treatment or that worsened relative to pretreatment state.

Concentration of Cortisol, Aldosterone, Corticosterone, 11-Deoxycortisol, Deoxycorticosterone and Dehydroepiandrostenedione Sulphate (DHEA-S) in blood was measured in nanogram per deciliter (ng/dL).

The time from start of study treatment to the development/worsening of pain due to prostate cancer requiring one or more of the following treatments: 1- Opioid therapy (therapy with morphine like medicines for 10 out of 14 consecutive days); 2- Glucocorticoid therapy; 3- Initiation of >= 5 mg of prednisolone for 10 out of 14 consecutive days; 4- Radionuclide therapy; 5- Radiation therapy (x-ray or cobalt treatment); 6- Chemotherapy (treatment of disease by chemical agents). Participants who do not experience prostate cancer pain were censored on their last day on study. Time to prostate cancer pain progression was measured by Kaplan-Meier method.

The Cmax is defined as maximum observed analyte concentration.

The Tmax is defined as actual sampling time to reach maximum observed plasma concentration. The analyte concentration associated with Tmax is referred to as Cmax.

Area under the plasma concentration time-curve from time zero to the last quantifiable concentration (AUClast).

AUC (0 - ∞)= Area under the plasma concentration versus time curve (AUC) from time zero (pre-dose) to extrapolated infinite time (0 - ∞). It is obtained from AUC (0 - t) plus AUC (t - ∞).

Plasma decay half-life is the time measured for the plasma concentration to decrease by one half.

The actual sampling time of last measurable (non-below the limit of quantification [BQL]) analyte concentration. The analyte concentration associated with Tlast is referred to as Clast.