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

NCT02861573 | Recruiting Phase 1 FDA Drug

• 6 other identifiers: 3475-365KEYNOTE-365MK-3475-3652023-506987-15-00U1111-1294-75772016-002312-41
• Study Type: interventional
• Target: 1,200
• Locations: 15 countries
• Sites: 21

Brief 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

Keywords

Metastatic Castration-Resistant Prostate Cancer; mCRPC; PD1; PD-1; PDL1; PD-L1

Outcome Measures

Primary Outcomes (4)

• Percentage of Participants With a Decrease of ≥50% in Prostatic Specific Antigen (PSA)

  From Baseline Measured Every 3 Weeks Until Radiographic Progression Estimated to be Approximately 2 Years

• Number of Participants with Adverse Events (AEs)

  Assessed Every 3 Weeks Over the Duration of the Study Which is Estimated to be Approximately 2 Years

• Number of Participants Discontinuing Study Drug Due to AEs

  Assessed Every 3 Weeks Over the Duration of the Study Which is Estimated to be Approximately 2 Years

• Objective Response Rate (ORR) Based on Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) Assessed by Blinded Independent Central Review (BICR)

  Assessed Over the Duration of the Study Which is Estimated to be Approximately 2 Years

Secondary Outcomes (7)

• Disease Control Rate (DCR) Based on Prostate Cancer Working Group 3 (PCWG3)-modified RECIST 1.1 Assessed by BICR

  Assessed Over the Duration of the Study Which is Estimated to be Approximately 2 Years

• Overall Survival (OS)

  Assessed Over the Duration of the Study Which is Estimated to be Approximately 2 Years

• Duration of Response (DOR) Based on PCWG3-modified RECIST 1.1 Assessed by BICR

  Assessed Over the Duration of the Study Which is Estimated to be Approximately 2 Years

• ORR Based on PCWG3-modified RECIST 1.1 Assessed by BICR

  Assessed Over the Duration of the Study Which is Estimated to be Approximately 2 Years

• Time to PSA Progression

  Assessed Over the Duration of the Study Which is Estimated to be Approximately 2 Years

Study Arms (12)

Pembrolizumab+Olaparib

EXPERIMENTAL

Participants with adenocarcinoma (AC) mCRPC in Cohort A will receive pembrolizumab 200 mg intravenously (IV) on Day 1 of each 3-week dosing cycle (Q3W) and olaparib 400 mg capsules or 300 mg tablets by mouth (PO) twice a day (BID) continuously from Day 1 of Cycle 1. Treatment with pembrolizumab will continue until progression or a maximum of 35 treatment cycles (up to 2 years). Treatment with olaparib will continue until progression. Participants who must discontinue 1 of the 2 drugs in the combination due to adverse events may continue the study with the other combination drug.

Biological: Pembrolizumab 200 mg; Drug: Olaparib 400 mg; Drug: Olaparib 300 mg

Pembrolizumab+Docetaxel+Prednisone

EXPERIMENTAL

Participants with AC mCRPC in Cohort B will receive pembrolizumab 200 mg IV on Day 1 Q3W, docetaxel 75 mg/m\^2 IV on Day 1 Q3W, and prednisone 5 mg tablet PO BID continuously from Day 1 of Cycle 1. Participants will only be permitted to receive a maximum of 10 cycles of docetaxel and prednisone. Treatment with pembrolizumab will continue for a maximum of 35 cycles (up to 2 years) or until progression. Participants who must discontinue 1 of the 2 drugs due to adverse events in the combination may continue the study with the other combination drug.

Biological: Pembrolizumab 200 mg; Drug: Docetaxel 75 mg/m^2; Drug: Prednisone 5 mg; Other: Dexamethasone 8 mg

Pembrolizumab+Enzalutamide

EXPERIMENTAL

Participants with AC mCRPC in Cohort C will receive pembrolizumab 200 mg IV on Day 1 Q3W and enzalutamide 160 mg PO every day (QD) continuously from Day 1 of Cycle 1. Treatment with pembrolizumab will continue until progression or a maximum of 35 treatment cycles (up to 2 years). Treatment with enzalutamide will continue until progression. Participants who must discontinue 1 of the 2 drugs in the combination due to adverse events may continue the study with the other combination drug.

Biological: Pembrolizumab 200 mg; Drug: Enzalutamide 160 mg

Pembrolizumab+Abiraterone+Prednisone

EXPERIMENTAL

Participants with AC mCRPC in Cohort D will receive pembrolizumab 200 mg IV on Day 1 Q3W, abiraterone acetate 1000 mg PO QD and prednisone 5 mg tablet PO BID continuously from Day 1 of Cycle 1. Treatment with pembrolizumab will continue for a maximum of 35 cycles (up to 2 years) or until progression. Participants who must discontinue 1 of the 2 drugs due to adverse events in the combination may continue the study with the other combination drug.

Biological: Pembrolizumab 200 mg; Drug: Prednisone 5 mg; Drug: Abiraterone acetate 1000 mg

Pembrolizumab+Lenvatinib: AC

EXPERIMENTAL

Participants with AC mCRPC in Cohort E will receive pembrolizumab 200 mg IV on Day 1 Q3W, and lenvatinib 20 mg PO QD continuously from Day 1 of Cycle 1. Treatment with pembrolizumab will continue for a maximum of 35 cycles (up to 2 years) or until progression. Participants who must discontinue 1 of the 2 drugs due to adverse events in the combination may continue the study with the other combination drug.

Biological: Pembrolizumab 200 mg; Drug: Lenvatinib

Pembrolizumab+Lenvatinib:t-NE

EXPERIMENTAL

Participants with neuroendocrine (t-NE) mCRPC in Cohort F will receive pembrolizumab 200 mg IV on Day 1 Q3W, and lenvatinib 20 mg PO QD continuously from Day 1 of Cycle 1. Treatment with pembrolizumab will continue for a maximum of 35 cycles (up to 2 years) or until progression. Participants who must discontinue 1 of the 2 drugs due to adverse events in the combination may continue the study with the other combination drug.

Biological: Pembrolizumab 200 mg; Drug: Lenvatinib

Pembrolizumab/Vibostolimab coformulation

EXPERIMENTAL

Participants with AC mCRPC in Cohort G will receive a coformulation fixed dose combination of 200 mg pembrolizumab and 200 mg vibostolimab (MK-7684) Q3W IV from Day 1 of Cycle 1. Treatment will continue for a maximum of 35 cycles (up to 2 years) or until progression.

Biological: Pembrolizumab/Vibostolimab coformulation

Pembrolizumab/Vibostolimab coformulation:t-NE

EXPERIMENTAL

Participants with t-NE mCRPC in Cohort H will receive a coformulation fixed dose combination of 200 mg pembrolizumab and 200 mg vibostolimab (MK-7684) Q3W IV from Day 1 of Cycle 1. Treatment will continue for a maximum of 35 cycles (up to 2 years) or until progression.

Biological: Pembrolizumab/Vibostolimab coformulation

Pembrolizumab+Carboplatin+Etoposide

EXPERIMENTAL

Participants with neuroendocrine mCRPC in Cohort I Arm 1 will receive pembrolizumab 200 mg IV on Day 1 Q3W + carboplatin titrated to an area under the plasma drug concentration-time curve \[AUC\] 5 IV on Day 1 Q3W + etoposide 100 mg/m\^2 IV on Days 1, 2, and 3 Q3W. Treatment with pembrolizumab will continue for a maximum of 35 cycles (up to 2 years) or until progression. Treatment with carboplatin+etoposide will continue for a maximum of 4 cycles (up to 2.8 months). Participants who must discontinue 1 or 2 of the 3 drugs due to adverse events in the combination may continue the study with the other combination drug/drugs.

Biological: Pembrolizumab 200 mg; Drug: Carboplatin; Drug: Etoposide

Carboplatin+Etoposide

EXPERIMENTAL

Participants with neuroendocrine mCRPC in Cohort I Arm 2 will receive carboplatin titrated to an area under the plasma drug concentration-time curve \[AUC\] 5 IV on Day 1 Q3W + etoposide 100 mg/m\^2 IV on Days 1, 2, and 3 Q3W. Treatment will continue for a maximum of 35 cycles (up to 2 years) or until progression. Treatment with carboplatin+etoposide will continue for a maximum of 4 cycles (up to 2.8 months). Participants who must discontinue 1 of the 2 drugs due to adverse events in the combination may continue the study with the other combination drug.

Drug: Carboplatin; Drug: Etoposide

Belzutifan

EXPERIMENTAL

Participants with AC mCRPC in Cohort J will receive belzutifan 120mg QD in the initial cohort. If an efficacy signal is detected in this arm based on a totality of evidence, Cohort J may be expanded further where participants will be randomized 1:1 to receive either belzutifan 120 mg QD or belzutifan 120 mg QD and pembrolizumab 200 mg Q3W. Treatment will continue for a maximum of 35 cycles (up to 2 years) or until progression.

Biological: Belzutifan 120mg

Pembrolizumab+Belzutifan

EXPERIMENTAL

Participants with AC mCRPC in Cohort J will receive belzutifan 120mg QD in the initial cohort. If an efficacy signal is detected in this arm based on a totality of evidence, Cohort J may be expanded further where participants will be randomized 1:1 to receive either belzutifan 120 mg QD or belzutifan 120 mg QD and pembrolizumab 200 mg Q3W. Treatment will continue for a maximum of 35 cycles (up to 2 years) or until progression.

Biological: Pembrolizumab 200 mg; Biological: Belzutifan 120mg

Interventions

Pembrolizumab 200 mg BIOLOGICAL

IV Q3W

Also known as: KEYTRUDA®, MK-3475

Pembrolizumab+Abiraterone+Prednisone; Pembrolizumab+Belzutifan; Pembrolizumab+Carboplatin+Etoposide; Pembrolizumab+Docetaxel+Prednisone; Pembrolizumab+Enzalutamide; Pembrolizumab+Lenvatinib: AC; Pembrolizumab+Lenvatinib:t-NE; Pembrolizumab+Olaparib

Olaparib 400 mg DRUG

Eight 50-mg capsules PO BID

Also known as: LYNPARZA®, MK-7339

Pembrolizumab+Olaparib

Docetaxel 75 mg/m^2 DRUG

IV Q3W

Also known as: TAXOTERE®

Pembrolizumab+Docetaxel+Prednisone

Prednisone 5 mg DRUG

One 5-mg tablet PO BID

Pembrolizumab+Abiraterone+Prednisone; Pembrolizumab+Docetaxel+Prednisone

Enzalutamide 160 mg DRUG

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

Also known as: XTANDI®

Pembrolizumab+Enzalutamide

Dexamethasone 8 mg OTHER

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

Pembrolizumab+Docetaxel+Prednisone

Olaparib 300 mg DRUG

Two 150-mg tablets PO BID

Also known as: LYNPARZA®, MK-7339

Pembrolizumab+Olaparib

Abiraterone acetate 1000 mg DRUG

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

Also known as: ZYTIGA®

Pembrolizumab+Abiraterone+Prednisone

Lenvatinib DRUG

20 mg PO QD

Also known as: LENVIMA®, MK-7902

Pembrolizumab+Lenvatinib: AC; Pembrolizumab+Lenvatinib:t-NE

Pembrolizumab/Vibostolimab coformulation BIOLOGICAL

IV Q3W

Also known as: MK-7684A

Pembrolizumab/Vibostolimab coformulation; Pembrolizumab/Vibostolimab coformulation:t-NE

Carboplatin DRUG

IV Q3W

Also known as: PARAPLATIN®

Carboplatin+Etoposide; Pembrolizumab+Carboplatin+Etoposide

Etoposide DRUG

IV on Days 1, 2 and 3 of each cycle

Also known as: TOPOSAR™

Carboplatin+Etoposide; Pembrolizumab+Carboplatin+Etoposide

Belzutifan 120mg BIOLOGICAL

PO QD

Also known as: WELIREG™

Belzutifan; Pembrolizumab+Belzutifan

Eligibility Criteria

• Age: 18 Years+
• Gender Eligibility Details: Participants must be male and be ≥18 years of age on day of signing informed consent.
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• For Cohorts A, B, C, D, E, G, J: Has histologically- or cytologically-confirmed adenocarcinoma of the prostate without small cell histology
• For Cohorts F, H, I: Has t-NE or de novo metastatic prostate cancer defined by ≥1% neuroendocrine cells that are located in discrete regions of a recent biopsy specimen from a metastasis as determined by the investigational site and confirmed by central histology review prior to enrollment. Epstein criteria of neuroendocrine differentiation in prostate cancer is used for eligibility. Specimens must have one of the morphologies of Small cell carcinoma or Large cell neuroendocrine carcinoma (LCNEC) or Mixed (small or large cell) NE carcinoma - acinar adenocarcinoma with positive IHC confirmed by central pathology review
• Is able to provide tumor tissue from a site not previously irradiated as follows: Cohorts A, E, G and J: must provide a core or excisional biopsy from soft tissue or bone biopsy within 1 year of screening and after developing mCRPC; Cohort B: must provide an archival tumor tissue sample or tumor tissue from a newly obtained core or excisional biopsy from soft tissue if the lesion is clinically accessible; Cohorts C and D with soft tissue disease: must provide a core or excisional biopsy from a soft tissue lesion if clinically accessible within 1 year of screening and after developing mCRPC and an archival specimen if available; and Cohorts F, H, and I must provide a core or excisional biopsy from soft tissue or a bone biopsy. For de novo metastatic neuroendocrine prostate participants, biopsies must be performed within 1 year of screening. Participants with bone metastasis only must provide an archival tumor tissue specimen
• Has prostate cancer progression within 6 months prior to screening, as determined by the investigator, by means of one of the following: PSA progression as defined by a minimum of 2 rising PSA levels with an interval of ≥1 week between each assessment where the PSA value at screening should be ≥2 ng/mL; radiographic disease progression in soft tissue based on Response Evaluation Criteria In Solid Tumors Version 1.1 criteria with or without PSA progression; radiographic disease progression in bone defined as the appearance of 2 or more new bone lesions on bone scan with or without PSA progression. Participants with de novo neuroendocrine prostate cancer will not need to provide evidence of progression within 6 months
• Has ongoing androgen deprivation with serum testosterone \<50 ng/dL (\<2.0 nM). Treatment with luteinizing hormone-releasing hormone agonists or antagonists for all cohorts must have been initiated ≥4 weeks prior to first dose of study therapy and must be continued throughout the study. Participants with de novo metastatic NE prostate cancer will not be required to have been previously treated with androgen deprivation therapy (ADT). ADT must be started in these participants by the time of treatment allocation/randomization
• Participants receiving bone resorptive therapy (including, but not limited to bisphosphonate or receptor activator of nuclear factor kappa-β ligand inhibitor) must be on stable doses for ≥4 weeks prior to first dose of study therapy
• Must be abstinent from heterosexual intercourse, refrain from donating sperm, or agree to use contraception (unless confirmed to be azoospermic) during the intervention period starting with the first dose of study therapy. The length of time required to continue contraception after the last dose of study intervention for each study intervention is as follows: 7 days for abiraterone acetate and lenvatinib; 30 days for enzalutamide; and 95 days for olaparib, docetaxel, and carboplatin/etoposide. No contraception measures are required during and after the intervention period for pembrolizumab/vibostolimab coformulation
• Has a performance status of 0, 1, or 2 on the Eastern Cooperative Oncology Group (ECOG) Performance Scale for Cohorts A and C and a performance status of 0 or 1 for Cohorts B, D, E, F, G, H, I and J within 10 days of study start
• For Cohort A: Has received docetaxel for mCRPC. Prior treatment with 1 other chemotherapy for mCRPC is allowed. Up to 2 second-generation hormonal manipulations (e.g., abiraterone acetate and/or enzalutamide) are allowed. Prior docetaxel for metastatic hormone-sensitive prostate cancer is allowed if ≥4 weeks have elapsed from the last dose of docetaxel prior to day 1 of Cycle 1
• For Cohort B: Has received prior treatment with either abiraterone acetate or enzalutamide (but not both) in the prechemotherapy mCRPC state. Participants in Cohort B must have received at least 4 weeks of either abiraterone or enzalutamide treatment (but not both) who failed treatment or became intolerant of the drug
• For Cohort C: Has received prior treatment with abiraterone acetate in the pre-chemotherapy mCRPC state without prior enzalutamide. Participants in Cohort C must have received at least 4 weeks of abiraterone treatment who failed treatment or become intolerant of the drug. Participants who received abiraterone acetate in the hormone-sensitive state will not be eligible
• For Cohort D: Has not received chemotherapy for mCRPC and has either not had prior second generation hormonal manipulation for mCRPC OR has previously been treated with enzalutamide for mCRPC and failed treatment or has become intolerant of the drug. Prior docetaxel for metastatic hormone-sensitive prostate cancer is allowed if ≥4 weeks have elapsed from the last dose of docetaxel. Prior treatment with abiraterone acetate in the hormone-sensitive metastatic setting is allowed as long as there was no progression on this agent and abiraterone acetate was not discontinued due to adverse events (AEs)
• For Cohorts E, G and J: Has received docetaxel for mCRPC. Prior treatment with 1 other chemotherapy for mCRPC is allowed. Up to 2 second-generation hormonal manipulations (eg, abiraterone acetate, enzalutamide, apalutamide, darolutamide or other next-generation hormonal agents \[NHA\]) are allowed. Participants who received prior ketoconazole for metastatic disease may be enrolled. If docetaxel chemotherapy is used more than once (eg, once for metastatic hormone-sensitive and once for mCRPC), it will be considered as 1 therapy. Prior docetaxel for metastatic hormone-sensitive prostate cancer (mHSPC) is allowed if ≥4 weeks have elapsed from the last dose of docetaxel prior to Day 1 of Cycle 1
• For Cohort F, H, and I: Participants must have received prior treatment with androgen deprivation therapy (ADT) for metastatic disease. Prior treatment with up to a total of 2 chemotherapies for mCRPC is allowed, as well as up to 2 second-generation hormonal manipulations for mCRPC. Participants who received prior ketoconazole for metastatic disease may be enrolled. Docetaxel for mHSPC is allowed in addition to docetaxel for mCRPC. If docetaxel chemotherapy is used more than once (eg, once for metastatic hormone-sensitive and once for mCRPC), it will be considered as 1 therapy

You may not qualify if:

• Has had a prior anticancer monoclonal antibody (mAb) within 4 weeks prior to first dose study therapy or who has not recovered (i.e., Grade ≤1 or at baseline) from AEs due to mAbs administered \>4 weeks earlier
• Has had prior chemotherapy, targeted small molecule therapy abiraterone treatment, enzalutamide treatment, or radiation therapy within 2 weeks prior to first dose of study therapy or who has not recovered (ie, Grade ≤1 or at baseline) from AEs due to a previously administered agent
• Is currently participating in and receiving study therapy or has participated in a study of an investigational agent and received study drug or used an investigational device within 4 weeks of treatment allocation/randomization
• Has a diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to treatment allocation/randomization
• Has had prior treatment with therapeutic radiopharmaceuticals for prostate cancer, such as Radium-223 or Leutitium-177, within 4 weeks prior to the first dose of trial treatment
• Has an active autoimmune disease that has required systemic treatment in past 2 years
• Has a history of (noninfectious) pneumonitis/interstitial lung disease that required steroids or current pneumonitis/interstitial lung disease
• Has previously participated in any other pembrolizumab trial, or received prior therapy with an anti-programmed cell death 1 (anti-PD-1), anti-programmed cell death ligand 1 (anti-PD-L1), and anti-programmed cell death ligand 1 (anti-PD-L2)
• Has a known history of Human Immunodeficiency Virus (HIV)
• Has known active Hepatitis B or Hepatitis C
• Has received a live vaccine or live-attenuated vaccine within 30 days of the first dose of study therapy
• Has known active central nervous system metastases and/or carcinomatous meningitis
• Has a "superscan" bone scan defined as an intense symmetric activity in the bones and diminished renal parenchymal activity on baseline bone scan such that the presence of additional metastases in the future could not be evaluated
• Has had prior solid, organ or bone marrow transplant
• For Cohort A: Has experienced a seizure or seizures within 6 months of study start or is currently being treated with cytochrome P450 enzyme (CYP) inducing anti-epileptic drugs for seizures

Sponsors & Collaborators

• Merck Sharp & Dohme LLC: lead

Study Sites (21)

Call for Information (Investigational Site 2041)

Aurora, Colorado, 80045, United States

RECRUITING

Call for Information (Investigational Site 2091)

Cleveland, Ohio, 44195, United States

RECRUITING

Call for Information (Investigational Site 2094)

Portland, Oregon, 97239, United States

RECRUITING

Call for Information (Investigational Site 0008)

Pittsburgh, Pennsylvania, 15232, United States

RECRUITING

Call for Information (Investigational Site 0019)

Myrtle Beach, South Carolina, 29572, United States

RECRUITING

Call for Information (Investigational Site 2090)

Germantown, Tennessee, 38138, United States

RECRUITING

Call for Information (Investigational Site 0016)

Seattle, Washington, 98109, United States

RECRUITING

MSD Australia

North Ryde, Australia

RECRUITING

Merck Canada

Kirkland, Quebec, H9H 4M7, Canada

RECRUITING

MSD Denmark

Glostrup Municipality, Denmark

RECRUITING

MSD France

Paris, France

RECRUITING

MSD Ireland (Human Health) Ltd.

Dublin, Ireland

RECRUITING

MSD Italia S.r.l.

Rome, Italy

RECRUITING

MSD Comercializadora, S. de R.L. de C.V.

Mexico City, Mexico

RECRUITING

Merck Sharp & Dohme BV

Haarlem, Netherlands

RECRUITING

Merck Sharp & Dohme (New Zealand) Ltd.,

Auckland, New Zealand

RECRUITING

MSD Polska Sp. Z o.o.

Warsaw, Poland

RECRUITING

Merck Sharp and Dohme de Espana S.A.

Madrid, Spain

RECRUITING

MSD Sweden

Stockholm, Sweden

RECRUITING

Merck Sharp & Dohme Ilaclari Ltd. Sti

Istanbul, Turkey (Türkiye)

RECRUITING

Merck Sharp & Dohme Ltd.

London, United Kingdom

RECRUITING

Related Publications (4)

• Yu EY, Ferrario C, Linch MD, Stoeckle M, Laguerre B, Arranz JA, Todenhofer T, Fong PC, Piulats JM, Berry W, Emmenegger U, Mourey L, Joshua AM, Mar N, Appleman LJ, Conter HJ, Gravis G, Li XT, Schloss C, Poehlein C, de Bono JS. Pembrolizumab plus Abiraterone Acetate and Prednisone in Patients with Chemotherapy-naive Metastatic Castration-resistant Prostate Cancer: Results from KEYNOTE-365 Cohort D. Eur Urol Oncol. 2025 Jun;8(3):641-651. doi: 10.1016/j.euo.2024.05.013. Epub 2024 Jun 25.

  PMID: 38926066 RESULT

• Yu EY, Berry WR, Gurney H, Retz M, Conter HJ, Laguerre B, Fong PCC, Ferrario C, Todenhofer T, Gravis G, Piulats JM, Emmenegger U, Shore ND, Romano E, Mourey L, Li XT, Poehlein CH, Schloss C, Appleman LJ, de Bono JS. Pembrolizumab and Enzalutamide in Patients with Abiraterone Acetate-Pretreated Metastatic Castration-Resistant Prostate Cancer: Cohort C of the Phase 1b/2 KEYNOTE-365 Study. Eur Urol Oncol. 2024 Jun;7(3):509-518. doi: 10.1016/j.euo.2023.10.008. Epub 2023 Nov 7.

  PMID: 37940446 RESULT

• Fong PC, Kwiatkowski M, Mosca A, Valderrama BP, Li C, Huang YH, Zedan AH, Kuc K, Wiechno P, Laguerre B, Gonzalez-Billalabeitia E, Osipov M, Sener Dede D, Goh JC, Daugaard G, Zhu P, Imai K, Liu Y, Arranz Arija JA. Vibostolimab Coformulated with Pembrolizumab in Participants with Docetaxel-pretreated Metastatic Castration-resistant Prostate Cancer: KEYNOTE-365 Cohort G. Eur Urol Focus. 2026 Mar;12(2):168-173. doi: 10.1016/j.euf.2025.07.018. Epub 2025 Aug 11.

  PMID: 40796417 DERIVED

• Yu EY, Kolinsky MP, Berry WR, Retz M, Mourey L, Piulats JM, Appleman LJ, Romano E, Gravis G, Gurney H, Bogemann M, Emmenegger U, Joshua AM, Linch M, Sridhar S, Conter HJ, Laguerre B, Massard C, Li XT, Schloss C, Poehlein CH, de Bono JS. Pembrolizumab Plus Docetaxel and Prednisone in Patients with Metastatic Castration-resistant Prostate Cancer: Long-term Results from the Phase 1b/2 KEYNOTE-365 Cohort B Study. Eur Urol. 2022 Jul;82(1):22-30. doi: 10.1016/j.eururo.2022.02.023. Epub 2022 Apr 6.

  PMID: 35397952 DERIVED

Related Links

• Merck Clinical Trials Information
• Plain Language Summary

MeSH Terms

Interventions

pembrolizumab; olaparib; Docetaxel; Prednisone; enzalutamide; Dexamethasone; Abiraterone Acetate; lenvatinib; Carboplatin; Etoposide; belzutifan

Intervention Hierarchy (Ancestors)

Taxoids; Cyclodecanes; Cycloparaffins; Hydrocarbons, Alicyclic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Diterpenes; Terpenes; Pregnadienediols; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Pregnadienetriols; Steroids, Fluorinated; Androstenes; Androstanes; Coordination Complexes; Podophyllotoxin; Tetrahydronaphthalenes; Naphthalenes; Polycyclic Aromatic Hydrocarbons; Hydrocarbons, Aromatic; Glucosides; Glycosides; Carbohydrates

Study Officials

• Medical Director

  Merck Sharp & Dohme LLC

  STUDY DIRECTOR

Central Study Contacts

Toll Free Number

CONTACT

1-888-577-8839; Trialsites@msd.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 3, 2016
• First Posted: August 10, 2016
• Study Start: November 17, 2016
• Primary Completion (Estimated): October 22, 2027
• Study Completion (Estimated): July 24, 2028
• Last Updated: February 17, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will share

Locations

IT (1); IE (1); SE (1); ES (1); US (7); DK (1); AU (1); CA (1); FR (1); ME (1); PL (1); TU (1); NZ (1); NL (1); GB (1)