Study of Pembrolizumab (MK-3475) Plus Docetaxel Versus Placebo Plus Docetaxel in Chemotherapy-naïve Metastatic Castration-resistant Prostate Cancer (mCRPC) (MK-3475-921/KEYNOTE-921)

NCT03834506 | Completed Phase 3 Results DMC FDA Drug

• 5 other identifiers: 3475-921MK-3475-921KEYNOTE-921JAPAC-CTI2018-004116-22
• Study Type: interventional
• Target: 1,030
• Locations: 20 countries
• Sites: 208

Brief Summary

The purpose of this study is to assess the efficacy and safety of the combination of pembrolizumab (MK-3475) and docetaxel in the treatment of men with metastatic castration-resistant prostate cancer (mCRPC) who have not received chemotherapy for mCRPC but have progressed on or are intolerant to Next Generation Hormonal Agent (NHA). There are two primary study hypotheses. Hypothesis 1: The combination of pembrolizumab plus docetaxel plus prednisone is superior to placebo plus docetaxel plus prednisone with respect to Overall Survival (OS). Hypothesis 2: The combination of pembrolizumab plus docetaxel plus prednisone is superior to placebo plus docetaxel plus prednisone with respect to Radiographic Progression-free Survival (rPFS) per Prostate Cancer Working Group (PCWG)-modified Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as assessed by blinded independent central review.

Conditions

Prostatic Neoplasms

Keywords

Programmed Cell Death 1 (PD 1, PD-1); Programmed Cell Death 1 Ligand 1 (PDL 1, PD-L1); Programmed Cell Death 1 Ligand 2 (PDL 2, PD-L2)

Outcome Measures

Primary Outcomes (2)

• Overall Survival (OS)

  OS was defined as the time from randomization to death due to any cause. The OS was calculated using the product-limit Kaplan-Meier (K-M) method for censored data. Participants without documented death at the time of the analysis were censored at the date of the last follow-up.

  Up to 36.5 months

• Radiographic Progression-free Survival (rPFS) Per Prostate Cancer Working Group (PCWG)-Modified Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as Assessed by Blinded Independent Central Review (BICR)

  rPFS was defined as the time from randomization to occurrence of: radiological tumor progression using RECIST 1.1 as assessed by BICR; progression of bone lesions using PCWG criteria; or death due to any cause. Radiological progression as per RECIST 1.1 was ≥20% increase in sum of diameters of target lesions and progression of existing non-target lesions. Progression of bone lesions by PCWG criteria was the appearance of ≥2 new bone lesions on bone scan, that have been confirmed to not represent tumor flare, and was persistent for ≥6 weeks. The rPFS was calculated using the product-limit K-M method for censored data. Participants without a rPFS event were censored at the date of last disease assessment.

  Up to approximately 28 months

Secondary Outcomes (10)

• Time to Initiation of the First Subsequent Anti-cancer Therapy (TFST)

  Up to approximately 28 months

• Prostate-specific Antigen (PSA) Response Rate

  Up to 36.5 months

• Objective Response Rate (ORR) Per Prostate Cancer Working Group (PCWG)-Modified Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as Assessed by Blinded Independent Central Review (BICR)

  Up to 36.5 months

• Duration of Response (DOR) Per Prostate Cancer Working Group (PCWG)-Modified Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as Assessed by Blinded Independent Central Review (BICR)

  Up to 36.5 months

• Time to Pain Progression (TTPP) as Assessed by Brief Pain Inventory-Short Form (BPI-SF) Item 3 ("Worst Pain in 24 Hours") and Opiate Analgesic Use Assessed by the Analgesic Quantification Algorithm (AQA) Score

  Up to 36.5 months

Study Arms (2)

Pembrolizumab+Docetaxel

EXPERIMENTAL

Participants receive pembrolizumab 200 mg by intravenous (IV) infusion on Day 1 of each 21-day cycle (Q3W) for up to a maximum of 35 cycles (approximately 2 years) PLUS docetaxel 75 mg/m\^2 by IV infusion on Day 1 of each 21-day cycle (Q3W) for a maximum of 10 cycles (approximately 7 months). Participants also concomitantly receive dexamethasone 8 mg by oral tablets at 12 hours, 3 hours, and 1 hour prior to docetaxel administration and prednisone 5 mg by oral tablets twice daily during each 21-day docetaxel cycle.

Biological: Pembrolizumab; Drug: Docetaxel; Drug: Prednisone; Drug: Dexamethasone

Placebo+Docetaxel

PLACEBO COMPARATOR

Participants receive placebo by IV infusion on Day 1 of each 21-day cycle (Q3W) for up to a maximum of 35 cycles (approximately 2 years) PLUS docetaxel 75 mg/m\^2 by IV infusion on Day 1 of each 21-day cycle (Q3W) for a maximum of 10 cycles (approximately 7 months). Participants also concomitantly receive dexamethasone 8 mg by oral tablets at 12 hours, 3 hours, and 1 hour prior to docetaxel administration and prednisone 5 mg by oral tablets twice daily during each 21-day docetaxel cycle.

Drug: Docetaxel; Drug: Prednisone; Drug: Placebo; Drug: Dexamethasone

Interventions

Pembrolizumab BIOLOGICAL

IV infusion

Also known as: MK-3475, KEYTRUDA®

Pembrolizumab+Docetaxel

Docetaxel DRUG

IV infusion

Also known as: TAXOTERE®

Pembrolizumab+Docetaxel; Placebo+Docetaxel

Prednisone DRUG

Oral tablets

Pembrolizumab+Docetaxel; Placebo+Docetaxel

Placebo DRUG

IV infusion

Also known as: Normal saline or dextrose infusion

Placebo+Docetaxel

Dexamethasone DRUG

Oral tablets

Also known as: DECADRON®

Pembrolizumab+Docetaxel; Placebo+Docetaxel

Eligibility Criteria

• Age: 18 Years+
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may not qualify if:

• Has histologically- or cytologically-confirmed adenocarcinoma of the prostate without small cell histology
• Has prostate cancer progression while on androgen deprivation therapy (or post bilateral orchiectomy) within 6 months prior to screening
• Has current evidence of metastatic disease documented by either bone lesions on bone scan and/or soft tissue disease by computed tomography/magnetic resonance imaging (CT/MRI)
• Has received prior treatment with one (but not more than one) NHA (eg, abiraterone acetate, enzalutamide, apalutamide, or darolutamide) for metastatic hormone-sensitive prostate cancer (mHSPC) or castration-resistant prostate cancer (CRPC) and either a) progressed through treatment OR b) has become intolerant of the drug
• Has ongoing androgen deprivation with serum testosterone \<50 ng/dL (\<2.0 nM)
• Participants receiving bone resorptive therapy (including, but not limited to, bisphosphonate or denosumab) must have been on stable doses prior to randomization
• Participants must agree to the following during the study treatment period and for at least 120 days after the last dose of pembrolizumab or for at least 180 days after the last dose of docetaxel (whichever is longer): Refrain from donating sperm PLUS Use contraception unless confirmed to be azoospermic (vasectomized or secondary to medical cause)
• Participants must agree to use male condom when engaging in any activity that allows for passage of ejaculate to another person of any sex
• Has provided newly obtained core or excisional biopsy (obtained within 12 months of screening) from soft tissue not previously irradiated (samples from tumors progressing in a prior site of radiation are allowed). Participants with bone only or bone predominant disease may provide a bone biopsy sample
• Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 assessed within 7 days of randomization
• Has a known additional malignancy that is progressing or has required active treatment in the last 3 years
• Has an active autoimmune disease that has required systemic treatment in past 2 years
• Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy
• Has undergone major surgery including local prostate intervention (excluding prostate biopsy) within 28 days prior to randomization and not recovered adequately from the toxicities and/or complications
• Has a gastrointestinal disorder affecting absorption or is unable to swallow tablets/capsules

Sponsors & Collaborators

• Merck Sharp & Dohme LLC: lead

Study Sites (215)

University of South Alabama, Mitchell Cancer Institute ( Site 0065)

Mobile, Alabama, 36604, United States

Location

St. Joseph Heritage Healthcare ( Site 0069)

Fullerton, California, 92835, United States

Location

University of Southern California Norris Comprehensive Cancer Center ( Site 0061)

Los Angeles, California, 90033, United States

Location

USC Norris Oncology Hematology Newport Beach ( Site 0093)

Newport Beach, California, 92663, United States

Location

University of California San Francisco ( Site 0023)

San Francisco, California, 94158, United States

Location

University of Colorado Cancer Center ( Site 0022)

Aurora, Colorado, 80045, United States

Location

Yale Cancer Center ( Site 0038)

New Haven, Connecticut, 06510, United States

Location

Moffitt Cancer Center ( Site 0080)

Tampa, Florida, 33612, United States

Location

Georgia Cancer Center at Augusta University ( Site 0026)

Augusta, Georgia, 30912, United States

Location

Mount Sinai Hospital Medical Center ( Site 0042)

Chicago, Illinois, 60608, United States

Location

Methodist Hospital- Merriillville ( Site 0008)

Merrillville, Indiana, 46410, United States

Location

Karmanos Cancer Institute ( Site 0077)

Detroit, Michigan, 48201, United States

Location

Henry Ford Health System ( Site 0039)

Detroit, Michigan, 48202-2608, United States

Location

Cancer & Hematology Centers of Western Michigan ( Site 0013)

Grand Rapids, Michigan, 49503, United States

Location

Washington University School of Medicine ( Site 0057)

St Louis, Missouri, 63110, United States

Location

St. Vincent Frontier Cancer Center ( Site 0016)

Billings, Montana, 59102, United States

Location

Nebraska Cancer Specialists ( Site 0034)

Omaha, Nebraska, 68130, United States

Location

Comprehensive Cancer Centers of Nevada ( Site 0092)

Las Vegas, Nevada, 89169, United States

Location

John Theurer Cancer Center at Hackensack University Medical Center ( Site 0004)

Hackensack, New Jersey, 07601, United States

Location

Associated Medical Professionals of NY ( Site 0060)

Syracuse, New York, 13210, United States

Location

Duke Cancer Center ( Site 0010)

Durham, North Carolina, 27710, United States

Location

W. G. Bill Hefner VA Medical Center ( Site 0029)

Salisbury, North Carolina, 28144, United States

Location

University Hospitals Cleveland Medical Center ( Site 0036)

Cleveland, Ohio, 44106, United States

Location

Oregon Health Sciences University ( Site 0031)

Portland, Oregon, 97239, United States

Location

Carolina Urologic Research Center ( Site 0070)

Myrtle Beach, South Carolina, 29572, United States

Location

Inova Schar Cancer Institute ( Site 0006)

Fairfax, Virginia, 22031-4867, United States

Location

Virginia Cancer Institute ( Site 0052)

Richmond, Virginia, 23230, United States

Location

Blue Ridge Cancer Care ( Site 0086)

Roanoke, Virginia, 24014, United States

Location

Centro de Oncologia e Investigacion Buenos Aires COIBA ( Site 1013)

Berazategui, Buenos Aires, B1884BBF, Argentina

Location

Instituto de Investigaciones Clinicas ( Site 1000)

Mar del Plata, Buenos Aires, B7600FZN, Argentina

Location

Centro de Diagnostico Urologico ( Site 1008)

Buenos Aires, Buenos Aires F.D., C1120AAT, Argentina

Location

Hospital Britanico de Buenos Aires ( Site 1006)

Buenos Aires, Buenos Aires F.D., C1280AEB, Argentina

Location

Sanatorio Parque ( Site 1002)

Rosario, Santa Fe Province, S2000DSV, Argentina

Location

Instituto de Investigaciones Metabolicas [Buenos Aires, Argentina] ( Site 1011)

Buenos Aires, C1012AAR, Argentina

Location

Hospital Aleman ( Site 1004)

Buenos Aires, C1118AAT, Argentina

Location

Instituto Medico Alexander Fleming ( Site 1010)

Buenos Aires, C1426ANZ, Argentina

Location

CEMAIC ( Site 1014)

Córdoba, X5008HHW, Argentina

Location

St George Hospital ( Site 0157)

Kogarah, New South Wales, 2217, Australia

Location

Macquarie University ( Site 0151)

Macquarie University, New South Wales, 2109, Australia

Location

Port Macquarie Base Hospital ( Site 0153)

Port Macquarie, New South Wales, 2444, Australia

Location

Calvary Mater Newcastle ( Site 0148)

Waratah, New South Wales, 2298, Australia

Location

Redcliffe Hospital ( Site 0161)

Redcliffe, Queensland, 4020, Australia

Location

John Flynn Hospital & Medical Centre ( Site 0164)

Tugun, Queensland, 4224, Australia

Location

Hollywood Private Hospital ( Site 0163)

Nedlands, Western Australia, 6009, Australia

Location

Medizinische Universitat Graz ( Site 0374)

Graz, Styria, 8036, Austria

Location

Ordensklinikum Linz GmbH Elisabethinen ( Site 0373)

Linz, Upper Austria, 4020, Austria

Location

SCRI-CCCIT GesmbH ( Site 0371)

Salzburg, 5020, Austria

Location

Medizinische Universitaet Wien ( Site 0375)

Vienna, 1090, Austria

Location

Hospital de Caridade de Ijui ( Site 1038)

Ijuí, Rio Grande do Sul, 98700-000, Brazil

Location

Uniao Brasileira de Educacao e Assistencia Hospital Sao Lucas da Pucrs ( Site 1021)

Porto Alegre, Rio Grande do Sul, 90610-000, Brazil

Location

Centro de Novos Tratamentos Itajai - Clinica de Neoplasias Litoral ( Site 1035)

Itajaí, Santa Catarina, 88301-215, Brazil

Location

Hospital de Base de Sao Jose de Rio Preto ( Site 1022)

São José do Rio Preto, São Paulo, 15090-000, Brazil

Location

A.C. Camargo Cancer Center ( Site 1026)

São Paulo, 01509-900, Brazil

Location

Nova Scotia Health Authority QEII-HSC ( Site 0114)

Halifax, Nova Scotia, B3H 2Y9, Canada

Location

Hamilton Health Sciences-Juravinski Cancer Centre ( Site 0116)

Hamilton, Ontario, L8V5C2, Canada

Location

Grand River Hospital ( Site 0120)

Kitchener, Ontario, N2G 1G3, Canada

Location

Lakeridge Health ( Site 0117)

Oshawa, Ontario, L1G 2B9, Canada

Location

Sunnybrook Research Institute ( Site 0108)

Toronto, Ontario, M4N 3M5, Canada

Location

Princess Margaret Cancer Centre ( Site 0107)

Toronto, Ontario, M5G 2M9, Canada

Location

CHU de Quebec-Universite Laval-Hotel Dieu de Quebec ( Site 0103)

Québec, Quebec, G1R 2J6, Canada

Location

CIUSSS du Bas Saint Laurent - Hopital Regional de Rimouski ( Site 0102)

Rimouski, Quebec, G5L 5T1, Canada

Location

CIUSSS de l Estrie - CHUS - Centre Hosp. Univ. Sherbrooke ( Site 0105)

Sherbrooke, Quebec, J1H 5N4, Canada

Location

Fundacion Arturo Lopez Perez ( Site 1049)

Santiago, Region M. de Santiago, 7500921, Chile

Location

Pontificia Universidad Catolica de Chile ( Site 1047)

Santiago, Region M. de Santiago, 8330032, Chile

Location

Bradford Hill Centro de Investigaciones Clinicas ( Site 1044)

Santiago, Region M. de Santiago, 8420383, Chile

Location

Centro Investigación del Cáncer James Lind ( Site 1041)

Temuco, Región de la Araucanía, 4780000, Chile

Location

Rey y Oreilly Limitada ( Site 1048)

Temuco, Región de la Araucanía, 4810148, Chile

Location

Centro de Investigaciones Clinicas Vina del Mar ( Site 1042)

Viña del Mar, Región de Valparaíso, 2540488, Chile

Location

Peking University First Hospital ( Site 1303)

Beijing, Beijing Municipality, 100034, China

Location

The Fifth Medical Center of PLA General Hospital ( Site 1307)

Beijing, Beijing Municipality, 100071, China

Location

Beijing Cancer Hospital ( Site 1305)

Beijing, Beijing Municipality, 100142, China

Location

The First Affiliated Hospital of Xiamen University ( Site 1319)

Xiamen, Fujian, 361003, China

Location

Sun Yat Sen Memorial Hospital ( Site 1323)

Guangzhou, Guangdong, 510220, China

Location

The First Affiliated Hospital of Guangzhou Medical University ( Site 1330)

Guangzhou, Guangdong, 510230, China

Location

Harbin Medical University Cancer Hospital ( Site 1326)

Harbin, Heilongjiang, 150081, China

Location

Henan Cancer Hospital ( Site 1321)

Zhengzhou, Henan, 450008, China

Location

Hubei Cancer Hospital ( Site 1329)

Wuhan, Hubei, 430079, China

Location

Hunan Cancer Hospital ( Site 1320)

Changsha, Hunan, 410013, China

Location

Nanjing Drum Tower Hospital ( Site 1312)

Nanjing, Jiangsu, 210008, China

Location

Fudan University Shanghai Cancer Center ( Site 1300)

Shanghai, Shanghai Municipality, 200032, China

Location

Zhongshan Hospital Fudan University ( Site 1301)

Shanghai, Shanghai Municipality, 200032, China

Location

The Second Affiliated Hospital of Zhejiang University School of Medicine ( Site 1309)

Hangzhou, Zhejiang, 310009, China

Location

Zhejiang Provincial People's Hospital ( Site 1310)

Hangzhou, Zhejiang, 310014, China

Location

Hospital Pablo Tobon Uribe ( Site 1066)

Medellín, Antioquia, 050034, Colombia

Location

Biomelab S A S ( Site 1067)

Barranquilla, Atlántico, 080002, Colombia

Location

Clinica de la Costa Ltda. ( Site 1073)

Barranquilla, Atlántico, 080020, Colombia

Location

Instituto Nacional de Cancerologia E.S.E ( Site 1061)

Bogotá, Bogota D.C., 110321, Colombia

Location

Clinica Colsanitas S.A. Sede Clinica Universitaria Colombia ( Site 1062)

Bogotá, Bogota D.C., 111321, Colombia

Location

Sociedad de Oncología Y Hematología del Cesar S.A.S. ( Site 1068)

Valledupar, Cesar Department, 200001, Colombia

Location

Oncomedica S.A. ( Site 1057)

Montería, Departamento de Córdoba, 230002, Colombia

Location

Oncologos del Occidente S.A. ( Site 1072)

Pereira, Risaralda Department, 660001, Colombia

Location

Centro Medico Imbanaco de Cali S.A ( Site 1064)

Cali, Valle del Cauca Department, 760042, Colombia

Location

Hemato Oncologos S.A. ( Site 1065)

Cali, Valle del Cauca Department, 760042, Colombia

Location

C.H. de Saint Quentin ( Site 0481)

Saint-Quentin, Aisne, 02321, France

Location

Clinique Sainte Anne ( Site 0431)

Strasbourg, Alsace, 67000, France

Location

Centre Jean Perrin ( Site 0434)

Clermont-Ferrand, Auvergne, 63011, France

Location

Centre Leon Berard ( Site 0422)

Lyon, Auvergne, 69373, France

Location

Institut Paoli Calmettes. ( Site 0419)

Marseille, Bouches-du-Rhone, 13009, France

Location

CHU Jean Minjoz ( Site 0423)

Besançon, Doubs, 25000, France

Location

CHU de Brest -Site Hopital Morvan ( Site 0441)

Brest, Finistere, 29200, France

Location

Institut Bergonie ( Site 0421)

Bordeaux, Gironde, 33076, France

Location

Institut Claudius Regaud IUCT Oncopole ( Site 0418)

Toulouse, Haute-Garonne, 31059, France

Location

Hopital Foch ( Site 0428)

Suresnes, Hauts-de-Seine, 92151, France

Location

Institut De Cancerologie De L Ouest ( Site 0448)

Saint-Herblain, Loire-Atlantique, 44805, France

Location

Centre Hospitalier Regional du Orleans ( Site 0430)

Orléans, Loiret, 45100, France

Location

Centre D Oncologie de Gentilly ( Site 0432)

Nancy, Meurthe-et-Moselle, 54100, France

Location

C.H.U. Lyon Sud ( Site 0436)

Pierre-Bénite, Rhone, 69310, France

Location

CHU Amiens Picardie Site Sud Amiens ( Site 0438)

Amiens, Somme, 80000, France

Location

Institut Gustave Roussy ( Site 0416)

Villejuif, Val-de-Marne, 94800, France

Location

Institut Sainte Catherine ( Site 0447)

Avignon, Vaucluse, 84000, France

Location

Institut Mutualiste Montsouris ( Site 0446)

Paris, 75014, France

Location

Universitaetsklinikum Freiburg - Medizinische Klinik ( Site 0304)

Freiburg im Breisgau, Baden-Wurttemberg, 79106, Germany

Location

Universitaetsklinikum in Mannheim ( Site 0314)

Mannheim, Baden-Wurttemberg, 68167, Germany

Location

Studienpraxis Urologie ( Site 0309)

Nürtingen, Baden-Wurttemberg, 72622, Germany

Location

Universitaetsklinik fuer Urologie ( Site 0307)

Tübingen, Baden-Wurttemberg, 72076, Germany

Location

Klinikum Rechts der Isar ( Site 0300)

Munich, Bavaria, 81675, Germany

Location

Universitaetsklinik der Paracelsus Medizinischen Privatuniversitaet ( Site 0318)

Nuremberg, Bavaria, 90419, Germany

Location

Universitaetsklinikum Wuerzburg ( Site 0302)

Würzburg, Bavaria, 97080, Germany

Location

Universitaetsklinikum Goettingen ( Site 0345)

Göttingen, Lower Saxony, 37075, Germany

Location

Uniklinik RWTH Aachen ( Site 0308)

Aachen, North Rhine-Westphalia, 52074, Germany

Location

Universitaetsklinikum des Saarlandes ( Site 0348)

Homburg, Saarland, 66421, Germany

Location

Universitaetsklinikum Jena ( Site 0305)

Jena, Thuringia, 07747, Germany

Location

Charite Universitaetsmedizin Berlin ( Site 0301)

Berlin, 10117, Germany

Location

Cork University Hospital ( Site 0727)

Cork, T12 YE02, Ireland

Location

Tallaght University Hospital ( Site 0730)

Dublin, D24 NROA, Ireland

Location

Mid Western Cancer Centre ( Site 0728)

Limerick, Ireland

Location

Assaf Harofeh MC ( Site 0547)

Beer Yaakov-Zerifin, 7030001, Israel

Location

Soroka Medical Center ( Site 0548)

Beersheba, 8410101, Israel

Location

Rambam Medical Center ( Site 0543)

Haifa, 3109601, Israel

Location

Hadassah Ein Kerem Medical Center ( Site 0546)

Jerusalem, 9112001, Israel

Location

Meir Medical Center ( Site 0544)

Kfar Saba, 4428164, Israel

Location

Rabin Medical Center ( Site 0545)

Petah Tikva, 4941492, Israel

Location

Chaim Sheba Medical Center ( Site 0541)

Ramat Gan, 5262000, Israel

Location

Sourasky Medical Center ( Site 0542)

Tel Aviv, 6423906, Israel

Location

Istituto Clinico Humanitas Research Hospital ( Site 0452)

Rozzano, Milano, 20089, Italy

Location

Azienda Ospedaliera Cannizzaro ( Site 0458)

Catania, 95126, Italy

Location

A.O. Universitaria di Modena ( Site 0454)

Modena, 41100, Italy

Location

Istituto Nazionale Tumori IRCCS Fondazione Pascale ( Site 0457)

Napoli, 80131, Italy

Location

Azienda Ospedaliera San Camillo Forlanini ( Site 0455)

Roma, 00152, Italy

Location

Azienda Ospedaliera Santa Maria Terni ( Site 0456)

Terni, 05100, Italy

Location

Presidio Ospedaliero Santa Chiara ( Site 0451)

Trento, 38122, Italy

Location

National Cancer Center Hospital East ( Site 0702)

Kashiwa, Chiba, 277-8577, Japan

Location

Toho University Sakura Medical Center ( Site 0703)

Sakura, Chiba, 285-8741, Japan

Location

National Hospital Organization Shikoku Cancer Center ( Site 0716)

Matsuyama, Ehime, 791-0280, Japan

Location

Kanazawa University Hospital ( Site 0701)

Kanazawa, Ishikawa-ken, 920-8641, Japan

Location

Kitasato University Hospital ( Site 0705)

Sagamihara, Kanagawa, 252-0375, Japan

Location

Yokohama City University Medical Center ( Site 0706)

Yokohama, Kanagawa, 232-0024, Japan

Location

Nara Medical University Hospital ( Site 0715)

Kashihara, Nara, 634-8522, Japan

Location

Kindai University Hospital ( Site 0714)

Sayama, Osaka, 589-8511, Japan

Location

Osaka University Hospital ( Site 0713)

Suita, Osaka, 565-0871, Japan

Location

Saitama Medical University International Medical Center ( Site 0708)

Hidaka, Saitama, 1932, Japan

Location

Dokkyo Medical University Saitama Medical Center ( Site 0707)

Koshigaya, Saitama, 343-8555, Japan

Location

Hamamatsu University Hospital ( Site 0720)

Hamamatsu, Shizuoka, 431-3192, Japan

Location

Yamaguchi University Hospital ( Site 0717)

Ube, Yamaguchi, 755-8505, Japan

Location

Chiba Cancer Center ( Site 0704)

Chiba, 260-8717, Japan

Location

Kyushu University Hospital ( Site 0718)

Fukuoka, 812-8582, Japan

Location

University of Miyazaki Hospital ( Site 0721)

Miyazaki, 889-1692, Japan

Location

Nagasaki University Hospital ( Site 0719)

Nagasaki, 852-8501, Japan

Location

Toranomon Hospital ( Site 0711)

Tokyo, 105-8470, Japan

Location

Nippon Medical School Hospital ( Site 0709)

Tokyo, 113-8603, Japan

Location

Keio University Hospital ( Site 0710)

Tokyo, 160-8582, Japan

Location

Ziekenhuis Gelderse Vallei ( Site 0485)

Ede, Gelderland, 6746 RP, Netherlands

Location

Radboud University Medical Center ( Site 0470)

Nijmegen, Gelderland, 6525 GA, Netherlands

Location

VieCuri Medisch Centrum ( Site 0487)

Venlo, Limburg, 5912 BL, Netherlands

Location

Jeroen Bosch Ziekenhuis ( Site 1200)

's-Hertogenbosch, North Brabant, 5223 GZ, Netherlands

Location

Catharina Ziekenhuis ( Site 0472)

Eindhoven, North Brabant, 5623 EJ, Netherlands

Location

Antoni van Leeuwenhoek Ziekenhuis ( Site 0480)

Amsterdam, North Holland, 1066 CX, Netherlands

Location

Ziekenhuis Hilversum ( Site 0466)

Hilversum, North Holland, 1213 XZ, Netherlands

Location

Ziekenhuisgroep Twente ( Site 0469)

Hengelo, Overijssel, 7555 DL, Netherlands

Location

Medisch Centrum Leeuwarden ( Site 0477)

Leeuwarden, Provincie Friesland, 8934 AD, Netherlands

Location

Reinier de Graaf Groep ( Site 0484)

Delft, South Holland, 2625 AD, Netherlands

Location

Hagaziekenhuis ( Site 1201)

The Hague, South Holland, 2545 AA, Netherlands

Location

Chelyabinsk Regional Clinical Oncological Dispensary ( Site 0565)

Chelyabinsk, Chelyabinsk Oblast, 454087, Russia

Location

Krasnoyarsk Regional Clinical Oncological Dispensary ( Site 0585)

Krasnoyarsk, Krasnoyarsk Krai, 660133, Russia

Location

SBIH City clinical hospital named after D.D. Pletniov ( Site 0575)

Moscow, Moscow, 105077, Russia

Location

Russian Scientific Center of Radiology ( Site 0559)

Moscow, Moscow, 117485, Russia

Location

Central Clinical Hospital with Polyclinic ( Site 0562)

Moscow, Moscow, 121359, Russia

Location

National Medical Research Radiological Center ( Site 0556)

Moscow, Moscow, 125284, Russia

Location

Volga District Medical Center Federal Medical and Biological Agency ( Site 0572)

Nizhny Novgorod, Nizhny Novgorod Oblast, 603074, Russia

Location

Omsk Clinical Oncology Dispensary ( Site 0568)

Omsk, Omsk Oblast, 644013, Russia

Location

SBHI Samara Regional Clinical Oncology Dispensary ( Site 0576)

Samara, Samara Oblast, 443031, Russia

Location

Leningrad Regional Oncology Center ( Site 0588)

Saint Petersburg, Sankt-Peterburg, 188663, Russia

Location

Clinical Research Center of specialized types medical care-Oncology ( Site 0570)

Saint Petersburg, Sankt-Peterburg, 197758, Russia

Location

Russian Scientific Center of Radiology and Surgical Technologies ( Site 0567)

Saint Petersburg, Sankt-Peterburg, 197758, Russia

Location

SPb SBHI City Clinical Oncological Dispensary ( Site 0571)

Saint Petersburg, Sankt-Peterburg, 198255, Russia

Location

Tomsk National Research Medical Center of Russian Academy of Sciences ( Site 0579)

Tomsk, Tomsk Oblast, 634050, Russia

Location

National Cancer Center ( Site 0174)

Goyang-si, Kyonggi-do, 10408, South Korea

Location

Seoul National University Bundang Hospital ( Site 0175)

Seongnam-si, Kyonggi-do, 13620, South Korea

Location

Seoul National University Hospital ( Site 0171)

Seoul, 03080, South Korea

Location

Asan Medical Center ( Site 0176)

Seoul, 05505, South Korea

Location

Samsung Medical Center ( Site 0172)

Seoul, 06351, South Korea

Location

Instituto Catalan de Oncologia - ICO ( Site 0330)

L'Hospitalet de Llobregat, Barcelona, 08908, Spain

Location

Hospital Consorci Sanitari Parc Tauli ( Site 0335)

Sabadell, Barcelona, 08208, Spain

Location

Hospital Universitario Marques de Valdecilla ( Site 0336)

Santander, Cantabria, 39008, Spain

Location

Hospital Josep Trueta ( Site 0321)

Girona, Gerona, 17007, Spain

Location

Hospital del Mar ( Site 0333)

Barcelona, 08003, Spain

Location

Hospital Clinic ( Site 0323)

Barcelona, 08036, Spain

Location

Hospital Universitario Ramon y Cajal ( Site 0328)

Madrid, 28034, Spain

Location

Hospital Clinico San Carlos ( Site 0324)

Madrid, 28040, Spain

Location

Hospital Universitario HM Sanchinarro ( Site 0322)

Madrid, 28050, Spain

Location

Hospital Universitario Virgen de la Victoria ( Site 0337)

Málaga, 29016, Spain

Location

Hospital Virgen del Rocio ( Site 0329)

Seville, 41013, Spain

Location

National Cheng Kung University Hospital ( Site 0134)

Tainen, Tainan, 704, Taiwan

Location

China Medical University Hospital ( Site 0132)

Taichung, 40447, Taiwan

Location

Taichung Veterans General Hospital ( Site 0133)

Taichung, 40705, Taiwan

Location

National Taiwan University Hospital ( Site 0131)

Taipei, 10048, Taiwan

Location

Taipei Veterans General Hospital ( Site 0135)

Taipei, 11217, Taiwan

Location

University Hospitals Bristol NHS Foundation Trust ( Site 0530)

Bristol, Bristol, City of, BS2 8ED, United Kingdom

Location

Cambridge University Hospitals NHS Trust ( Site 0540)

Cambridge, Cambridgeshire, CB2 0QQ, United Kingdom

Location

Torbay Hospital ( Site 0532)

Torquay, Devon, TQ2 7AA, United Kingdom

Location

Weston Park Hospital ( Site 0539)

Sheffield, England, S10 2SJ, United Kingdom

Location

Royal Marsden Hospital ( Site 0526)

Sutton, England, SM2 5PT, United Kingdom

Location

Mount Vernon Cancer Centre ( Site 0536)

Northwood, Hertfordshire, HA6 2RN, United Kingdom

Location

Barts Cancer Institute ( Site 0483)

London, London, City of, EC1A 7BE, United Kingdom

Location

University of North Midlands NHS Foundation Trust ( Site 0527)

Stoke-on-Trent, Staffordshire, ST4 6QG, United Kingdom

Location

Related Publications (2)

• Petrylak DP, Ratta R, Matsubara N, Korbenfeld E, Gafanov R, Mourey L, Todenhofer T, Gurney H, Kramer G, Bergman AM, Zalewski P, De Santis M, Armstrong AJ, Gerritsen W, Pachynski R, Byun SS, Retz M, Levesque E, McDermott R, Bracarda S, Manneh R, Levartovsky M, Li XT, Schloss C, Poehlein CH, Fizazi K. Pembrolizumab Plus Docetaxel Versus Docetaxel for Previously Treated Metastatic Castration-Resistant Prostate Cancer: The Randomized, Double-Blind, Phase III KEYNOTE-921 Trial. J Clin Oncol. 2025 May 10;43(14):1638-1649. doi: 10.1200/JCO-24-01283. Epub 2025 Mar 5.

  PMID: 40043230 RESULT

• Petrylak DP, Ratta R, Gafanov R, Facchini G, Piulats JM, Kramer G, Flaig TW, Chandana SR, Li B, Burgents J, Fizazi K. KEYNOTE-921: Phase III study of pembrolizumab plus docetaxel for metastatic castration-resistant prostate cancer. Future Oncol. 2021 Sep;17(25):3291-3299. doi: 10.2217/fon-2020-1133. Epub 2021 Jun 8.

  PMID: 34098744 DERIVED

Related Links

• Merck Clinical Trials Information
• Plain Language Summary

MeSH Terms

Conditions

Prostatic Neoplasms; Parkinson Disease 4, Autosomal Dominant Lewy Body

Interventions

pembrolizumab; Docetaxel; Prednisone; Saline Solution; Dexamethasone; Calcium Dobesilate

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Intervention Hierarchy (Ancestors)

Taxoids; Cyclodecanes; Cycloparaffins; Hydrocarbons, Alicyclic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Diterpenes; Terpenes; Pregnadienediols; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Crystalloid Solutions; Isotonic Solutions; Solutions; Pharmaceutical Preparations; Pregnadienetriols; Steroids, Fluorinated; Benzenesulfonates; Benzene Derivatives; Hydrocarbons, Aromatic; Arylsulfonates; Arylsulfonic Acids; Sulfonic Acids; Sulfur Acids; Sulfur Compounds

Results Point of Contact

• Title: Senior Vice President, Global Clinical Development
• Organization: Merck Sharp & Dohme LLC

ClinicalTrialsDisclosure@msd.com

1-800-672-6372

Study Officials

• Medical Director

  Merck Sharp & Dohme LLC

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 6, 2019
• First Posted: February 8, 2019
• Study Start: May 2, 2019
• Primary Completion: June 20, 2022
• Study Completion: July 18, 2023
• Last Updated: July 18, 2025
• Results First Posted: June 18, 2023

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will share

Locations

GB (8); CA (9); ES (11); RU (14); IE (3); IL (8); AU (4); BR (5); CO (10); US (28); CL (6); JP (20); AR (9); NL (11); TW (5); KR (5); CN (15); IT (7); DE (12); FR (18)