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)
NCT ID: NCT03834506
Last Updated: 2025-07-18
Study Results
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View full resultsBasic Information
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COMPLETED
PHASE3
1030 participants
INTERVENTIONAL
2019-05-02
2023-07-18
Brief Summary
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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.
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Detailed Description
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The global study for MK-3475-921 enrolled 1030 participants. Of the 1030 total participants enrolled in the global study, 21 were also enrolled in the China extension study for MK-3475-921 (NCT04907227).
Conditions
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Study Design
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RANDOMIZED
PARALLEL
TREATMENT
TRIPLE
Study Groups
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Pembrolizumab+Docetaxel
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.
Pembrolizumab
IV infusion
Docetaxel
IV infusion
Prednisone
Oral tablets
Dexamethasone
Oral tablets
Placebo+Docetaxel
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.
Docetaxel
IV infusion
Prednisone
Oral tablets
Placebo
IV infusion
Dexamethasone
Oral tablets
Interventions
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Pembrolizumab
IV infusion
Docetaxel
IV infusion
Prednisone
Oral tablets
Placebo
IV infusion
Dexamethasone
Oral tablets
Other Intervention Names
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Eligibility Criteria
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Inclusion Criteria
* 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
Exclusion Criteria
* 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
* Has an active infection (including tuberculosis) requiring systemic therapy
* Has a history of (non-infectious) pneumonitis that required steroids or current pneumonitis
* Has known active human immunodeficiency virus (HIV), hepatitis B virus (HBV) or hepatitis C virus (HCV) infection
* Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis
* Has severe hypersensitivity (≥Grade 3) to pembrolizumab and/or any of its excipients
* Has symptomatic congestive heart failure (New York Heart Association Class III or IV heart disease)
* Has had a prior anti-cancer monoclonal antibody (mAb) prior to randomization or who has not recovered (i.e., Grade ≤1 or at baseline) from AEs due to mAbs
* Has used herbal products that may have hormonal anti-prostate cancer activity and/or are known to decrease PSA levels (e.g. saw palmetto) prior to randomization
* Has received prior treatment with radium or other therapeutic radiopharmaceuticals for prostate cancer
* Has received prior therapy with an anti-programmed cell death-1 (anti-PD-1), anti-programmed cell death-ligand 1 (anti-PD-L1), or anti PD-L2 agent or with an agent directed to another stimulatory or co-inhibitory T-cell receptor (e.g., cytotoxic T-lymphocyte-associated protein 4 \[CTLA-4\], OX-40, CD137)
* Has received prior treatment with docetaxel or another chemotherapy agent for mCRPC
* Has hypersensitivity to docetaxel or polysorbate 80
* Is currently receiving either strong or moderate inhibitors of cytochrome P450 (CYP)3A4 that cannot be discontinued for the duration of the study
* Has received prior targeted small molecule therapy or abiraterone acetate, enzalutamide, apalutamide, or darolutamide within 4 weeks prior to the first dose of study treatment, or has not recovered (i.e., Grade ≤1 or at baseline) from AEs due to a previously administered agent
* Has received prior radiotherapy to within 2 weeks of start of study treatment. Participants must have recovered from all radiation-related toxicities, not require corticosteroids, and not have had radiation pneumonitis
* Has received a live vaccine within 30 days prior to randomization
* Has received treatment with 5α reductase inhibitors (eg, finasteride or dutasteride), estrogens, and/or cyproterone within 4 weeks prior to randomization
* Has received prior treatment with ketoconazole for prostate cancer
* Is currently participating in or has participated in a study of an investigational agent or has used an investigational device within 4 weeks prior to the first dose of study treatment
* Has a "superscan" bone scan
* Is expecting to conceive or father children within the projected duration of the study, starting with the screening visit through 120 days after the last dose of study treatment
* Has had an allogenic tissue/solid organ transplant
18 Years
MALE
No
Sponsors
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Merck Sharp & Dohme LLC
INDUSTRY
Responsible Party
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Principal Investigators
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Medical Director
Role: STUDY_DIRECTOR
Merck Sharp & Dohme LLC
Locations
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University of South Alabama, Mitchell Cancer Institute ( Site 0065)
Mobile, Alabama, United States
St. Joseph Heritage Healthcare ( Site 0069)
Fullerton, California, United States
University of Southern California Norris Comprehensive Cancer Center ( Site 0061)
Los Angeles, California, United States
USC Norris Oncology Hematology Newport Beach ( Site 0093)
Newport Beach, California, United States
University of California San Francisco ( Site 0023)
San Francisco, California, United States
University of Colorado Cancer Center ( Site 0022)
Aurora, Colorado, United States
Yale Cancer Center ( Site 0038)
New Haven, Connecticut, United States
Moffitt Cancer Center ( Site 0080)
Tampa, Florida, United States
Georgia Cancer Center at Augusta University ( Site 0026)
Augusta, Georgia, United States
Mount Sinai Hospital Medical Center ( Site 0042)
Chicago, Illinois, United States
Methodist Hospital- Merriillville ( Site 0008)
Merrillville, Indiana, United States
Karmanos Cancer Institute ( Site 0077)
Detroit, Michigan, United States
Henry Ford Health System ( Site 0039)
Detroit, Michigan, United States
Cancer & Hematology Centers of Western Michigan ( Site 0013)
Grand Rapids, Michigan, United States
Washington University School of Medicine ( Site 0057)
St Louis, Missouri, United States
St. Vincent Frontier Cancer Center ( Site 0016)
Billings, Montana, United States
Nebraska Cancer Specialists ( Site 0034)
Omaha, Nebraska, United States
Comprehensive Cancer Centers of Nevada ( Site 0092)
Las Vegas, Nevada, United States
John Theurer Cancer Center at Hackensack University Medical Center ( Site 0004)
Hackensack, New Jersey, United States
Associated Medical Professionals of NY ( Site 0060)
Syracuse, New York, United States
Duke Cancer Center ( Site 0010)
Durham, North Carolina, United States
W. G. Bill Hefner VA Medical Center ( Site 0029)
Salisbury, North Carolina, United States
University Hospitals Cleveland Medical Center ( Site 0036)
Cleveland, Ohio, United States
Oregon Health Sciences University ( Site 0031)
Portland, Oregon, United States
Carolina Urologic Research Center ( Site 0070)
Myrtle Beach, South Carolina, United States
Inova Schar Cancer Institute ( Site 0006)
Fairfax, Virginia, United States
Virginia Cancer Institute ( Site 0052)
Richmond, Virginia, United States
Blue Ridge Cancer Care ( Site 0086)
Roanoke, Virginia, United States
Centro de Oncologia e Investigacion Buenos Aires COIBA ( Site 1013)
Berazategui, Buenos Aires, Argentina
Instituto de Investigaciones Clinicas ( Site 1000)
Mar del Plata, Buenos Aires, Argentina
Centro de Diagnostico Urologico ( Site 1008)
Buenos Aires, Buenos Aires F.D., Argentina
Hospital Britanico de Buenos Aires ( Site 1006)
Buenos Aires, Buenos Aires F.D., Argentina
Sanatorio Parque ( Site 1002)
Rosario, Santa Fe Province, Argentina
Instituto de Investigaciones Metabolicas [Buenos Aires, Argentina] ( Site 1011)
Buenos Aires, , Argentina
Hospital Aleman ( Site 1004)
Buenos Aires, , Argentina
Instituto Medico Alexander Fleming ( Site 1010)
Buenos Aires, , Argentina
CEMAIC ( Site 1014)
Córdoba, , Argentina
St George Hospital ( Site 0157)
Kogarah, New South Wales, Australia
Macquarie University ( Site 0151)
Macquarie University, New South Wales, Australia
Port Macquarie Base Hospital ( Site 0153)
Port Macquarie, New South Wales, Australia
Calvary Mater Newcastle ( Site 0148)
Waratah, New South Wales, Australia
Redcliffe Hospital ( Site 0161)
Redcliffe, Queensland, Australia
John Flynn Hospital & Medical Centre ( Site 0164)
Tugun, Queensland, Australia
Hollywood Private Hospital ( Site 0163)
Nedlands, Western Australia, Australia
Medizinische Universitat Graz ( Site 0374)
Graz, Styria, Austria
Ordensklinikum Linz GmbH Elisabethinen ( Site 0373)
Linz, Upper Austria, Austria
SCRI-CCCIT GesmbH ( Site 0371)
Salzburg, , Austria
Medizinische Universitaet Wien ( Site 0375)
Vienna, , Austria
Hospital de Caridade de Ijui ( Site 1038)
Ijuí, Rio Grande do Sul, Brazil
Uniao Brasileira de Educacao e Assistencia Hospital Sao Lucas da Pucrs ( Site 1021)
Porto Alegre, Rio Grande do Sul, Brazil
Centro de Novos Tratamentos Itajai - Clinica de Neoplasias Litoral ( Site 1035)
Itajaí, Santa Catarina, Brazil
Hospital de Base de Sao Jose de Rio Preto ( Site 1022)
São José do Rio Preto, São Paulo, Brazil
A.C. Camargo Cancer Center ( Site 1026)
São Paulo, , Brazil
Nova Scotia Health Authority QEII-HSC ( Site 0114)
Halifax, Nova Scotia, Canada
Hamilton Health Sciences-Juravinski Cancer Centre ( Site 0116)
Hamilton, Ontario, Canada
Grand River Hospital ( Site 0120)
Kitchener, Ontario, Canada
Lakeridge Health ( Site 0117)
Oshawa, Ontario, Canada
Sunnybrook Research Institute ( Site 0108)
Toronto, Ontario, Canada
Princess Margaret Cancer Centre ( Site 0107)
Toronto, Ontario, Canada
CHU de Quebec-Universite Laval-Hotel Dieu de Quebec ( Site 0103)
Québec, Quebec, Canada
CIUSSS du Bas Saint Laurent - Hopital Regional de Rimouski ( Site 0102)
Rimouski, Quebec, Canada
CIUSSS de l Estrie - CHUS - Centre Hosp. Univ. Sherbrooke ( Site 0105)
Sherbrooke, Quebec, Canada
Fundacion Arturo Lopez Perez ( Site 1049)
Santiago, Region M. de Santiago, Chile
Pontificia Universidad Catolica de Chile ( Site 1047)
Santiago, Region M. de Santiago, Chile
Bradford Hill Centro de Investigaciones Clinicas ( Site 1044)
Santiago, Region M. de Santiago, Chile
Centro Investigación del Cáncer James Lind ( Site 1041)
Temuco, Región de la Araucanía, Chile
Rey y Oreilly Limitada ( Site 1048)
Temuco, Región de la Araucanía, Chile
Centro de Investigaciones Clinicas Vina del Mar ( Site 1042)
Viña del Mar, Región de Valparaíso, Chile
Peking University First Hospital ( Site 1303)
Beijing, Beijing Municipality, China
The Fifth Medical Center of PLA General Hospital ( Site 1307)
Beijing, Beijing Municipality, China
Beijing Cancer Hospital ( Site 1305)
Beijing, Beijing Municipality, China
The First Affiliated Hospital of Xiamen University ( Site 1319)
Xiamen, Fujian, China
Sun Yat Sen Memorial Hospital ( Site 1323)
Guangzhou, Guangdong, China
The First Affiliated Hospital of Guangzhou Medical University ( Site 1330)
Guangzhou, Guangdong, China
Harbin Medical University Cancer Hospital ( Site 1326)
Harbin, Heilongjiang, China
Henan Cancer Hospital ( Site 1321)
Zhengzhou, Henan, China
Hubei Cancer Hospital ( Site 1329)
Wuhan, Hubei, China
Hunan Cancer Hospital ( Site 1320)
Changsha, Hunan, China
Nanjing Drum Tower Hospital ( Site 1312)
Nanjing, Jiangsu, China
Fudan University Shanghai Cancer Center ( Site 1300)
Shanghai, Shanghai Municipality, China
Zhongshan Hospital Fudan University ( Site 1301)
Shanghai, Shanghai Municipality, China
The Second Affiliated Hospital of Zhejiang University School of Medicine ( Site 1309)
Hangzhou, Zhejiang, China
Zhejiang Provincial People's Hospital ( Site 1310)
Hangzhou, Zhejiang, China
Hospital Pablo Tobon Uribe ( Site 1066)
Medellín, Antioquia, Colombia
Biomelab S A S ( Site 1067)
Barranquilla, Atlántico, Colombia
Clinica de la Costa Ltda. ( Site 1073)
Barranquilla, Atlántico, Colombia
Instituto Nacional de Cancerologia E.S.E ( Site 1061)
Bogotá, Bogota D.C., Colombia
Clinica Colsanitas S.A. Sede Clinica Universitaria Colombia ( Site 1062)
Bogotá, Bogota D.C., Colombia
Sociedad de Oncología Y Hematología del Cesar S.A.S. ( Site 1068)
Valledupar, Cesar Department, Colombia
Oncomedica S.A. ( Site 1057)
Montería, Departamento de Córdoba, Colombia
Oncologos del Occidente S.A. ( Site 1072)
Pereira, Risaralda Department, Colombia
Centro Medico Imbanaco de Cali S.A ( Site 1064)
Cali, Valle del Cauca Department, Colombia
Hemato Oncologos S.A. ( Site 1065)
Cali, Valle del Cauca Department, Colombia
C.H. de Saint Quentin ( Site 0481)
Saint-Quentin, Aisne, France
Clinique Sainte Anne ( Site 0431)
Strasbourg, Alsace, France
Centre Jean Perrin ( Site 0434)
Clermont-Ferrand, Auvergne, France
Centre Leon Berard ( Site 0422)
Lyon, Auvergne, France
Institut Paoli Calmettes. ( Site 0419)
Marseille, Bouches-du-Rhone, France
CHU Jean Minjoz ( Site 0423)
Besançon, Doubs, France
CHU de Brest -Site Hopital Morvan ( Site 0441)
Brest, Finistere, France
Institut Bergonie ( Site 0421)
Bordeaux, Gironde, France
Institut Claudius Regaud IUCT Oncopole ( Site 0418)
Toulouse, Haute-Garonne, France
Hopital Foch ( Site 0428)
Suresnes, Hauts-de-Seine, France
Institut De Cancerologie De L Ouest ( Site 0448)
Saint-Herblain, Loire-Atlantique, France
Centre Hospitalier Regional du Orleans ( Site 0430)
Orléans, Loiret, France
Centre D Oncologie de Gentilly ( Site 0432)
Nancy, Meurthe-et-Moselle, France
C.H.U. Lyon Sud ( Site 0436)
Pierre-Bénite, Rhone, France
CHU Amiens Picardie Site Sud Amiens ( Site 0438)
Amiens, Somme, France
Institut Gustave Roussy ( Site 0416)
Villejuif, Val-de-Marne, France
Institut Sainte Catherine ( Site 0447)
Avignon, Vaucluse, France
Institut Mutualiste Montsouris ( Site 0446)
Paris, , France
Universitaetsklinikum Freiburg - Medizinische Klinik ( Site 0304)
Freiburg im Breisgau, Baden-Wurttemberg, Germany
Universitaetsklinikum in Mannheim ( Site 0314)
Mannheim, Baden-Wurttemberg, Germany
Studienpraxis Urologie ( Site 0309)
Nürtingen, Baden-Wurttemberg, Germany
Universitaetsklinik fuer Urologie ( Site 0307)
Tübingen, Baden-Wurttemberg, Germany
Klinikum Rechts der Isar ( Site 0300)
Munich, Bavaria, Germany
Universitaetsklinik der Paracelsus Medizinischen Privatuniversitaet ( Site 0318)
Nuremberg, Bavaria, Germany
Universitaetsklinikum Wuerzburg ( Site 0302)
Würzburg, Bavaria, Germany
Universitaetsklinikum Goettingen ( Site 0345)
Göttingen, Lower Saxony, Germany
Uniklinik RWTH Aachen ( Site 0308)
Aachen, North Rhine-Westphalia, Germany
Universitaetsklinikum des Saarlandes ( Site 0348)
Homburg, Saarland, Germany
Universitaetsklinikum Jena ( Site 0305)
Jena, Thuringia, Germany
Charite Universitaetsmedizin Berlin ( Site 0301)
Berlin, , Germany
Cork University Hospital ( Site 0727)
Cork, , Ireland
Tallaght University Hospital ( Site 0730)
Dublin, , Ireland
Mid Western Cancer Centre ( Site 0728)
Limerick, , Ireland
Assaf Harofeh MC ( Site 0547)
Beer Yaakov-Zerifin, , Israel
Soroka Medical Center ( Site 0548)
Beersheba, , Israel
Rambam Medical Center ( Site 0543)
Haifa, , Israel
Hadassah Ein Kerem Medical Center ( Site 0546)
Jerusalem, , Israel
Meir Medical Center ( Site 0544)
Kfar Saba, , Israel
Rabin Medical Center ( Site 0545)
Petah Tikva, , Israel
Chaim Sheba Medical Center ( Site 0541)
Ramat Gan, , Israel
Sourasky Medical Center ( Site 0542)
Tel Aviv, , Israel
Istituto Clinico Humanitas Research Hospital ( Site 0452)
Rozzano, Milano, Italy
Azienda Ospedaliera Cannizzaro ( Site 0458)
Catania, , Italy
A.O. Universitaria di Modena ( Site 0454)
Modena, , Italy
Istituto Nazionale Tumori IRCCS Fondazione Pascale ( Site 0457)
Napoli, , Italy
Azienda Ospedaliera San Camillo Forlanini ( Site 0455)
Roma, , Italy
Azienda Ospedaliera Santa Maria Terni ( Site 0456)
Terni, , Italy
Presidio Ospedaliero Santa Chiara ( Site 0451)
Trento, , Italy
National Cancer Center Hospital East ( Site 0702)
Kashiwa, Chiba, Japan
Toho University Sakura Medical Center ( Site 0703)
Sakura, Chiba, Japan
National Hospital Organization Shikoku Cancer Center ( Site 0716)
Matsuyama, Ehime, Japan
Kanazawa University Hospital ( Site 0701)
Kanazawa, Ishikawa-ken, Japan
Kitasato University Hospital ( Site 0705)
Sagamihara, Kanagawa, Japan
Yokohama City University Medical Center ( Site 0706)
Yokohama, Kanagawa, Japan
Nara Medical University Hospital ( Site 0715)
Kashihara, Nara, Japan
Kindai University Hospital ( Site 0714)
Sayama, Osaka, Japan
Osaka University Hospital ( Site 0713)
Suita, Osaka, Japan
Saitama Medical University International Medical Center ( Site 0708)
Hidaka, Saitama, Japan
Dokkyo Medical University Saitama Medical Center ( Site 0707)
Koshigaya, Saitama, Japan
Hamamatsu University Hospital ( Site 0720)
Hamamatsu, Shizuoka, Japan
Yamaguchi University Hospital ( Site 0717)
Ube, Yamaguchi, Japan
Chiba Cancer Center ( Site 0704)
Chiba, , Japan
Kyushu University Hospital ( Site 0718)
Fukuoka, , Japan
University of Miyazaki Hospital ( Site 0721)
Miyazaki, , Japan
Nagasaki University Hospital ( Site 0719)
Nagasaki, , Japan
Toranomon Hospital ( Site 0711)
Tokyo, , Japan
Nippon Medical School Hospital ( Site 0709)
Tokyo, , Japan
Keio University Hospital ( Site 0710)
Tokyo, , Japan
Ziekenhuis Gelderse Vallei ( Site 0485)
Ede, Gelderland, Netherlands
Radboud University Medical Center ( Site 0470)
Nijmegen, Gelderland, Netherlands
VieCuri Medisch Centrum ( Site 0487)
Venlo, Limburg, Netherlands
Jeroen Bosch Ziekenhuis ( Site 1200)
's-Hertogenbosch, North Brabant, Netherlands
Catharina Ziekenhuis ( Site 0472)
Eindhoven, North Brabant, Netherlands
Antoni van Leeuwenhoek Ziekenhuis ( Site 0480)
Amsterdam, North Holland, Netherlands
Ziekenhuis Hilversum ( Site 0466)
Hilversum, North Holland, Netherlands
Ziekenhuisgroep Twente ( Site 0469)
Hengelo, Overijssel, Netherlands
Medisch Centrum Leeuwarden ( Site 0477)
Leeuwarden, Provincie Friesland, Netherlands
Reinier de Graaf Groep ( Site 0484)
Delft, South Holland, Netherlands
Hagaziekenhuis ( Site 1201)
The Hague, South Holland, Netherlands
Chelyabinsk Regional Clinical Oncological Dispensary ( Site 0565)
Chelyabinsk, Chelyabinsk Oblast, Russia
Krasnoyarsk Regional Clinical Oncological Dispensary ( Site 0585)
Krasnoyarsk, Krasnoyarsk Krai, Russia
SBIH City clinical hospital named after D.D. Pletniov ( Site 0575)
Moscow, Moscow, Russia
Russian Scientific Center of Radiology ( Site 0559)
Moscow, Moscow, Russia
Central Clinical Hospital with Polyclinic ( Site 0562)
Moscow, Moscow, Russia
National Medical Research Radiological Center ( Site 0556)
Moscow, Moscow, Russia
Volga District Medical Center Federal Medical and Biological Agency ( Site 0572)
Nizhny Novgorod, Nizhny Novgorod Oblast, Russia
Omsk Clinical Oncology Dispensary ( Site 0568)
Omsk, Omsk Oblast, Russia
SBHI Samara Regional Clinical Oncology Dispensary ( Site 0576)
Samara, Samara Oblast, Russia
Leningrad Regional Oncology Center ( Site 0588)
Saint Petersburg, Sankt-Peterburg, Russia
Clinical Research Center of specialized types medical care-Oncology ( Site 0570)
Saint Petersburg, Sankt-Peterburg, Russia
Russian Scientific Center of Radiology and Surgical Technologies ( Site 0567)
Saint Petersburg, Sankt-Peterburg, Russia
SPb SBHI City Clinical Oncological Dispensary ( Site 0571)
Saint Petersburg, Sankt-Peterburg, Russia
Tomsk National Research Medical Center of Russian Academy of Sciences ( Site 0579)
Tomsk, Tomsk Oblast, Russia
National Cancer Center ( Site 0174)
Goyang-si, Kyonggi-do, South Korea
Seoul National University Bundang Hospital ( Site 0175)
Seongnam-si, Kyonggi-do, South Korea
Seoul National University Hospital ( Site 0171)
Seoul, , South Korea
Asan Medical Center ( Site 0176)
Seoul, , South Korea
Samsung Medical Center ( Site 0172)
Seoul, , South Korea
Instituto Catalan de Oncologia - ICO ( Site 0330)
L'Hospitalet de Llobregat, Barcelona, Spain
Hospital Consorci Sanitari Parc Tauli ( Site 0335)
Sabadell, Barcelona, Spain
Hospital Universitario Marques de Valdecilla ( Site 0336)
Santander, Cantabria, Spain
Hospital Josep Trueta ( Site 0321)
Girona, Gerona, Spain
Hospital del Mar ( Site 0333)
Barcelona, , Spain
Hospital Clinic ( Site 0323)
Barcelona, , Spain
Hospital Universitario Ramon y Cajal ( Site 0328)
Madrid, , Spain
Hospital Clinico San Carlos ( Site 0324)
Madrid, , Spain
Hospital Universitario HM Sanchinarro ( Site 0322)
Madrid, , Spain
Hospital Universitario Virgen de la Victoria ( Site 0337)
Málaga, , Spain
Hospital Virgen del Rocio ( Site 0329)
Seville, , Spain
National Cheng Kung University Hospital ( Site 0134)
Tainen, Tainan, Taiwan
China Medical University Hospital ( Site 0132)
Taichung, , Taiwan
Taichung Veterans General Hospital ( Site 0133)
Taichung, , Taiwan
National Taiwan University Hospital ( Site 0131)
Taipei, , Taiwan
Taipei Veterans General Hospital ( Site 0135)
Taipei, , Taiwan
University Hospitals Bristol NHS Foundation Trust ( Site 0530)
Bristol, Bristol, City of, United Kingdom
Cambridge University Hospitals NHS Trust ( Site 0540)
Cambridge, Cambridgeshire, United Kingdom
Torbay Hospital ( Site 0532)
Torquay, Devon, United Kingdom
Weston Park Hospital ( Site 0539)
Sheffield, England, United Kingdom
Royal Marsden Hospital ( Site 0526)
Sutton, England, United Kingdom
Mount Vernon Cancer Centre ( Site 0536)
Northwood, Hertfordshire, United Kingdom
Barts Cancer Institute ( Site 0483)
London, London, City of, United Kingdom
University of North Midlands NHS Foundation Trust ( Site 0527)
Stoke-on-Trent, Staffordshire, United Kingdom
Countries
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References
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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.
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.
Provided Documents
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Document Type: Study Protocol and Statistical Analysis Plan
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Merck Clinical Trials Information
Plain Language Summary
Other Identifiers
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MK-3475-921
Identifier Type: OTHER
Identifier Source: secondary_id
KEYNOTE-921
Identifier Type: OTHER
Identifier Source: secondary_id
JAPAC-CTI
Identifier Type: REGISTRY
Identifier Source: secondary_id
2018-004116-22
Identifier Type: EUDRACT_NUMBER
Identifier Source: secondary_id
3475-921
Identifier Type: -
Identifier Source: org_study_id
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