A Study to Evaluate Enzalutamide After Abiraterone in Metastatic Castration-Resistant Prostate Cancer
Condition: Metastatic Castration-Resistant Prostate Cancer
MeSH terms: Prostatic Neoplasms
Intervention: Enzalutamide
Intervention description: Participants received 160 mg of enzalutamide (soft capsules) orally once daily.
Phase: Phase 4
Study type: Interventional
Primary purpose: Treatment
Intervention model: Single Group Assignment
Masking: None (Open Label)
Enrollment: 215.0
Sex: Male
Minimum age: 18 Years
Healthy volunteers: No
Keywords: MDV3100; Xtandi; Abiraterone; Metastatic Castration-Resistant Prostate Cancer; Enzalutamide

Summary:

      The objective of this study was to evaluate the efficacy and safety of enzalutamide treatment
      in patients with progressive metastatic castration-resistant prostate cancer previously
      treated with abiraterone acetate.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Subject has histologically confirmed adenocarcinoma of the prostate without
             neuro-endocrine differentiation or small cell features.

          -  Subject has metastatic disease documented by bone scan or by soft tissue disease
             observed by Computed Tomography/Magnetic Resonance Imaging (CT/MRI) at screening, or
             within ≤30 days prior to Day 1.

          -  In the setting of castrate levels of testosterone ≤1.7 nmol/L (or ≤50 ng/dL), subject
             has progressive disease at study entry defined as PSA rise determined by a minimum of
             2 rising PSA levels with an interval of ≥ 1 week between each assessment. The PSA
             value at the screening visit should be ≥ 2 ng/mL WITH or WITHOUT:

               -  Soft tissue disease progression defined by Response Evaluation Criteria In Solid
                  Tumors (RECIST 1.1) at screening, or within ≤30 days prior to Day 1. Measurable
                  disease is not required for entry. Lymph nodes ≥ 2 cm are considered measurable
                  disease (Prostate Cancer Clinical Trials Working Group (PCWG2)).

               -  Bone disease progression defined by at least 2 new lesions on bone scan at
                  screening, or within ≤30 days prior to Day 1.

          -  Subject must have received a minimum of 24 weeks of treatment with abiraterone acetate
             within its approved label indication and has discontinued use at least 4 weeks prior
             to start of study drug at Day 1.

          -  If the subject has received previous treatment with chemotherapy for prostate cancer,
             this must be limited to no more than one prior line of docetaxel, and must have been
             used prior to abiraterone acetate therapy.

          -  Subject receives and will continue to receive ongoing androgen deprivation with
             Luteinizing-hormone-releasing hormone (LHRH) analogue therapy throughout the course of
             the study or has had a bilateral orchiectomy.

          -  Subject is asymptomatic or mildly symptomatic from prostate cancer:

               -  The score on Brief Pain Inventory - Short Form (BPI-SF) Question #3 must be < 4.

               -  No use of opiate analgesics for prostate cancer-related pain currently or anytime
                  within 4 weeks prior to screening.

        Exclusion Criteria:

          -  Subject has prior use of ketoconazole for the treatment of prostate cancer.

          -  Subject has prior use of cabazitaxel.

          -  Subject has prior use of enzalutamide.

          -  Subject has received ANY anti-neoplastic therapy (including antiandrogens and
             chemotherapy) following abiraterone acetate discontinuation and prior to start of
             study drug at Day 1.

          -  Subject has a known or suspected hypersensitivity to enzalutamide, or any components
             of the formulation used.

          -  Subject has known or suspected brain metastases or active leptomeningeal disease.

          -  Subject has history of seizure or any condition that may predispose to seizure (e.g.,
             prior stroke or significant brain trauma).