Trial Purpose

The purpose of this study is to assess the safety and efficacy of pembrolizumab (MK-3475) combination therapy in patients with metastatic castrate resistant prostate cancer (mCRPC). There will be nine cohorts in this study: Cohort A will receive pembrolizumab + olaparib, Cohort B will receive pembrolizumab + docetaxel + prednisone, Cohort C will receive pembrolizumab + enzalutamide, Cohort D will receive pembrolizumab + abiraterone + prednisone Cohort E will receive pembrolizumab+lenvatinib, Cohort F will receive pembrolizumab+lenvatinib, Cohort G will receive pembrolizumab/vibostolimab coformulation (MK-7684A), Cohort H will receive pembrolizumab/vibostolimab coformulation and Cohort I will receive pembrolizumab+carboplatin+etoposide in Arm 1 and carboplatin+etoposide in Arm 2. Outcome measures will be assessed individually for each cohort.

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When speaking to your doctor, please have the trial identifier number available.

About The Study

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Phase 1

Tests the medicine or vaccine in a small group of 20 to 100 volunteers who are usually healthy, but not always. The trial often takes place in a hospital.

Phase 2

Tests the medicine or vaccine in approximately 100 to 500 volunteers. In the case of medicines, volunteers usually have the disease or condition the investigational medicine is designed to treat. In vaccine studies, the volunteers are usually healthy.

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  • Actual study start date 17 November 2016
  • Estimated primary completion date 30 May 2025
  • Estimated study completion date 30 May 2025


Only a qualified healthcare professional can determine your eligibility. However, this information may be useful in starting a conversation with your doctor.

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Metastatic Castration-resistant Prostate Cancer

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Age Range

18 - No Age Maximum

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Trial locations

Locations provided may not reflect the most current site information. Please call the number provided in the location results to confirm.