Conditions: Progressive Metastatic Prostate Cancer
Keywords: Enzalutamide Androgen receptor Prostate cancer Xtandi
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 395
Healthy volunteers: no

Brief summary:
Purpose of the study was to assess the effect of enzalutamide on time to Prostate Specific Antigen (PSA) progression as compared to placebo in chemotherapy naïve participants with progressive metastatic prostate cancer who have failed androgen deprivation therapy.

Detailed description:
The study was a multinational Phase 3, randomized, double-blind, placebo-controlled efficacy and safety study of oral enzalutamide (formerly MDV3100) in asymptomatic or mildly symptomatic participants with progressive metastatic prostate cancer who have disease progression despite androgen deprivation therapy. In order to join the study, participants could not have been previously treated with cytotoxic chemotherapy. Approximately 30 Chinese participants were allocated to the pharmacokinetic (PK) cohort. Participants in the PK cohort were required to be hospitalized from Day 1 before the randomization date to at least the completion of all the assessments planned on Day 3. All participants in the PK cohort underwent blood sampling for the PK analysis. Data reported in the results section was based on data cutoff dates of 20 Sept 2015 for efficacy and safety data and 20 Jan 2016 for PK outcome measures. The study completed double-blind period and is now in the open-label period.

Arms:
arm 1: Participants received 160 mg of enzalutamide orally once a day during double blind period until Prostate-Specific Antigen (PSA) progression and radiographic disease progression were centrally confirmed and 1 of the following 2 events became applicable to the participants: (1) initiation of cytotoxic chemotherapy or (2) initiation of an investigational agent for treatment of prostate cancer. Eligible participants who received enzalutamide during double blind and who provided consent to take part in open-label period continued to receive 160 mg of enzalutamide in open-label period orally once a day until PSA progression and radiographic disease progression were centrally confirmed and 1 of the following 2 events became applicable to the participants: (1) initiation of cytotoxic chemotherapy or (2) initiation of an investigational agent for treatment of prostate cancer. arm 2: Participants received enzalutamide matching placebo orally once a day during double-blind period until PSA progression and radiographic disease progression were centrally confirmed and 1 of the following 2 events became applicable to the participants: (1) initiation of cytotoxic chemotherapy or (2) initiation of an investigational agent for treatment of prostate cancer. arm 3: Eligible participants who received enzalutamide matching placebo during double-blind period and who provided consent to take part in open-label period, received 160 mg of enzalutamide orally once a day during open-label period until PSA progression and radiographic disease progression were centrally confirmed and 1 of the following 2 events became applicable to the participants: (1) initiation of cytotoxic chemotherapy or (2) initiation of an investigational agent for treatment of prostate cancer.

Interventions: intervention 1: Enzalutamide intervention 2: Placebo
Intervention descriptions: intervention 1: Oral intervention 2: Oral

Protocol document: