Study of Pembrolizumab (MK-3475) Combination Therapies in Metastatic Castration-Resistant Prostate Cancer (MK-3475-365/KEYNOTE-365)

Summary

The purpose of this study is to assess the safety and efficacy of pembrolizumab (MK-3475) combination therapy in participants with metastatic castration resistant prostate cancer (mCRPC). There will be ten 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, Cohort I will receive pembrolizumab+carboplatin+etoposide in Arm 1 and carboplatin+etoposide in Arm 2 and Cohort J will receive belzutifan in Arm1 and Pembrolizumab+belzutifan in Arm 2. Outcome measures will be assessed individually for each cohort.

Conditions

• Metastatic Castration-Resistant Prostate Cancer

Interventions

BIOLOGICAL

Pembrolizumab 200 mg

IV Q3W

DRUG

Olaparib 400 mg

Eight 50-mg capsules PO BID

DRUG

Docetaxel 75 mg/m^2

IV Q3W

DRUG

Prednisone 5 mg

One 5-mg tablet PO BID

DRUG

Enzalutamide 160 mg

Four 40-mg capsules, four 40-mg tablets, or two 80-mg tablets PO QD

OTHER

Dexamethasone 8 mg

Premedication for Cohort B given PO at 12, 3, and 1 hours prior to docetaxel infusion Q3W

DRUG

Olaparib 300 mg

Two 150-mg tablets PO BID

DRUG

Abiraterone acetate 1000 mg

Two 500-mg or four 250-mg tablets PO QD

DRUG

Lenvatinib

20 mg PO QD

BIOLOGICAL

Pembrolizumab/Vibostolimab coformulation

IV Q3W

DRUG

Carboplatin

IV Q3W

DRUG

Etoposide

IV on Days 1, 2 and 3 of each cycle

BIOLOGICAL

Belzutifan 120mg

PO QD

Sponsors & Collaborators

• Merck Sharp & Dohme LLC

  lead INDUSTRY

Principal Investigators

• Medical Director · Merck Sharp & Dohme LLC

Study Design

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

MALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2016-11-17

Primary Completion

2027-10-22

Completion

2028-07-24

FDA Drug

Yes

Countries

• United States
• Australia
• Canada
• Denmark
• France
• Ireland
• Italy
• Mexico
• Netherlands
• New Zealand
• Poland
• Spain
• Sweden
• Turkey (Türkiye)
• United Kingdom

Study Locations