Condition: Metastatic Castration-Resistant Prostate Cancer

Keynote 365 is a phase 1B/2 study  to assess the safety and efficacy of pembrolizumab (MK-3475) combination therapy in patients with metastatic castrate resistant prostate cancer (mCRPC). Currently enrolling cohorts are*:

Treatment emergent neuroendocrine carcinoma (t-NE)  cohorts

• Cohort I
  • Arm 1 pembrolizumab+carboplatin+etoposide
  • Arm 2 carboplatin+etoposide.

Entrance criteria for Cohort I:

• Prior androgen deprivation therapy (ADT) for metastatic prostate cancer
• < 2 chemotherapies for mCRPC
• < 2 second generation hormonal therapies for mCRPC
• No prior treatment for prostate cancer with platinum-containing drugs

Adenocarcinoma cohort:

• Cohort J
  • Arm J1 belzutifan
  • Arm J2 pembrolizumab + belzutifan (Arm J2 is not currently enrolling)

Entrance criteria for Cohort J:

• Prior docetaxel for metastatic castrate resistant prostate cancer (mCRPC)
• < 1 other chemotherapy for mCRPC
• < 2 second generation hormonal therapies

Additional criteria apply and only an HCP can determine if you are eligible.

Primary objectives :

1. Safety and tolerability of pembrolizumab combination therapies to estimate the PSA response rate for each combination cohort
2. Evaluate the Objective Response Rate (ORR) for each cohort based on RECIST 1.1 by Blinded Independent Review

* Enrollment status updated as of 18Sep2023