Study of Pembrolizumab (MK-3475) in Participants With Metastatic Castration-Resistant Prostate Cancer (mCRPC) Previously Treated With Chemotherapy (MK-3475-199/KEYNOTE-199)

This is a study of pembrolizumab (MK-3475, KEYTRUDA®) in participants with metastatic castration-resistant prostate cancer (mCRPC) previously treated with docetaxel-based chemotherapy. Participants will be enrolled into one of three cohorts: Cohort 1 (participants with programmed cell death ligand 1 [PD-L1]-positive, measurable disease), Cohort 2 (participants with PD-L1 negative, measurable disease), or Cohort 3 (participants with bone-metastases and non-measurable disease).


Study Type: Interventional
Allocation: Non-Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Phase II Trial of Pembrolizumab (MK-3475) in Subjects With Metastatic Castration-Resistant Prostate Cancer (mCRPC) Previously Treated With Chemotherapy (KEYNOTE-199)
Estimated Enrollment: 250
Study Start Date: June 2016
Estimated Study Completion Date: December 2019
Estimated Primary Completion Date: September 2018 (Final data collection date for primary outcome measure)

Arms:
- Experimental: Cohort 1: PD-L1 positive with measurable disease
- Experimental: Cohort 2: PD-L1 negative with measurable disease
- Experimental: Cohort 3: Bone-metastases with non-measurable disease