RADIANT: A Study of Radium-223 Dichloride (Xofigo) vs Enzalutamide or Abiraterone (ARPIs, Androgen Receptor Pathway Inhibitors) in Patients With Prostate Cancer That Has Spread to the Bones (mCRPC, Metastatic Castration-Resistant Prostate Cancer)

NCT ID: NCT04597125

Last Updated: 2026-01-13

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: PHASE4
• Total Enrollment: 654 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2020-11-09
• Study Completion Date: 2026-10-10

Brief Summary

Researchers in this study want to compare how well drug radium-223 dichloride (Xofigo) and new (novel) anti-hormonal (NAH) therapy work in participants with prostate gland cancer which has spread to the bone and progressed on or after one line of NAH therapy. Meanwhile researchers want to compare the safety of radium-223 dichloride and NAH therapy. Radium-223 dichloride is known as a radioactive drug that is taken up by bones after it is injected into the body. It works by giving off a type of radioactivity that travels a very short distance and kills the tumor cells that have spread to the bone without major effects to the healthy cells. It has been approved in many countries for the treatment of patients with prostate cancer which has spread to the bone. The NAH drugs used in this study will be either abiraterone acetate (Zytiga) (plus prednisone/prednisolone) or enzalutamide (Xtandi). Both of them are standard approved medications which are used in the treatment of advanced prostate cancer.

Participants in this study will receive either Radium-223 dichloride or a NAH therapy. Radium-223 dichloride will be given as an infusion into one of the veins on Day 1 of each 4-week cycle for a total of up to 6 cycles. Oral NAH therapy will be given per the standard approved dose once daily until the disease has progressed. Participants will visit the hospital or clinic every 2 weeks for the first 6 cycles, and only on the first day of each cycle from cycle 7 and onwards. Observation for each participant will last for about 2 years in total. Blood and urine samples will be collected from the participants and participants will be asked to complete questionnaires about the well-being and the pain.

Conditions

Metastatic Castrate Resistant Prostate Cancer (mCRPC)

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Arm A

Participants with bone dominant metastatic castration resistant prostate cancer (mCRPC) progressing on/after one line of NAH will be randomized to receive radium-223 dichloride

Group Type: EXPERIMENTAL

Radium-223 dichloride (Xofigo, BAY88-8223)

Intervention Type: DRUG

Participants will receive Radium-223 (BAY88-8223) every 4 weeks for a total of 6 administrations via intravenous (IV) injection

Arm B

Participants with bone dominant metastatic castration resistant prostate cancer (mCRPC) progressing on/after one line of NAH will be randomized to receive second novel anti-hormonal therapy (NAH)

Group Type: ACTIVE_COMPARATOR

NAH therapy

Intervention Type: DRUG

Participants will receive continuous NAH (either Abiraterone acetate plus prednisone/prednisolone \[AAP\] or enzalutamide) by mouth (per os) daily

Interventions

Radium-223 dichloride (Xofigo, BAY88-8223)

Participants will receive Radium-223 (BAY88-8223) every 4 weeks for a total of 6 administrations via intravenous (IV) injection

Intervention Type: DRUG

NAH therapy

Participants will receive continuous NAH (either Abiraterone acetate plus prednisone/prednisolone \[AAP\] or enzalutamide) by mouth (per os) daily

Intervention Type: DRUG

Other Intervention Names

Second novel anti-hormonal therapy

Eligibility Criteria

Inclusion Criteria

• Participants who have histologically confirmed adenocarcinoma of the prostate.
• Participants with mCRPC progressing on/after one line of an approved NAH (eg. abiraterone, enzalutamide, apalutamide, or darolutamide, after being treated for at least 3 months) in an authorized prostate cancer indication.
• One prior taxane treatment regimen (at least 2 cycles) for metastatic prostate cancer (mHSPC and mCRPC) or refusal or ineligibility of such a regimen.
• Prostate cancer progression documented by PSA according to the Prostate Cancer Working Group 3 (PCWG3) criteria or radiological progression according to RECIST, version 1.1.
• At least 2 bone metastases on bone scan within 4 weeks prior to randomization with no current or history of lung, liver, other visceral, and / or brain metastasis.
• Symptomatic prostate cancer. A worst pain score (WPS) of at least 1 on the Brief Pain Inventory-Short Form (BPI-SF) Question #3 (worst pain in last 24 hours). This is to be assessed once during the Screening period.
• Maintenance of medical castration or surgical castration with testosterone less than 50 ng/dL (1.7 nmol/L). If the participant is being treated with luteinizing hormone releasing hormone (LHRH) agonists or antagonists (participant who has not undergone orchiectomy), this therapy must have been initiated at least 4 weeks prior to randomization and must be continued throughout the study.
• Participants must be on a BHA treatment, such as bisphosphonates or denosumab treatment unless such treatment is contraindicated or not recommended per investigator's judgement and inclusion is agreed to by the medical monitor.
• Eastern Cooperative Oncology Group performance status (ECOG PS) 0 or 1.
• Life expectancy ≥ 6 months.
• Able to swallow abiraterone and prednisone/prednisolone or enzalutamide as whole tablets/capsules.
• Laboratory requirements:

• Absolute neutrophil count (ANC) ≥ 1.5 x 10^9/L
• Platelet count ≥ 100 x 10^9/L
• Hemoglobin (Hb) ≥ 9.0 g/dL (90 g/L; 5.6 mmol/L)
• Total bilirubin level ≤ 1.5 x institutional upper limit of normal (ULN) (except for participants with documented Gilbert's disease)
• Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 x ULN
• Creatinine ≤ 1.5 x ULN or estimated glomerular filtration rate (eGFR) ≥ 30 mL/min/1.73 m^2 as calculated using the Cockcroft-Gault equation
• International normalized ratio (INR) of prothrombin time (PT; PT-INR) and partial thromboplastin time (PTT) ≤ 1.5 times the ULN. Participants treated with warfarin or heparin will be allowed to participate in the study if no underlying abnormality in coagulation parameters exists per prior history; weekly evaluation of PT-INR / PTT will be required until stability is achieved (as defined by local standard of care and based on pre-study PT-INR / PTT values)
• Serum albumin > 30 g/L
• Serum potassium ≥ 3.5 mmol/L
• Capable of giving signed informed consent

Exclusion Criteria

• Active infection or other medical condition that would make prednisone / prednisolone (corticosteroid) use contraindicated.
• Any chronic medical condition requiring a higher dose of corticosteroid than 10 mg prednisone / prednisolone equivalent daily for more than 2 months.
• Pathological finding consistent with tumors with predominant neuroendocrine features or small cell carcinoma of the prostate.
• History of osteoporotic fracture
• History of visceral metastasis, or presence of visceral metastasis detected by screening imaging examinations.
• History of or known brain metastasis.
• Malignant lymphadenopathy exceeding 3 cm in short-axis diameter.
• Other malignancy treated within the last 3 years (except non-melanoma skin cancer or low-grade superficial bladder cancer)
• Imminent spinal cord compression based on clinical findings and / or magnetic resonance imaging (MRI). Participants with history of spinal cord compression should have completely recovered.
• Uncontrolled hypertension (systolic blood pressure ≥ 160 mmHg or diastolic blood pressure ≥ 95 mmHg). Participants with a history of hypertension are allowed provided blood pressure is controlled by anti-hypertensive treatment.
• Active or symptomatic viral hepatitis
• History of pituitary or adrenal dysfunction
• Any other serious illness or medical condition such as, but not limited to:

• Any infection ≥ National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 5.0 Grade 2
• Clinically significant heart disease as evidenced by myocardial infarction, or arterial thrombotic events in the past 6 months, severe or unstable angina, or New York Heart Association (NYHA) Class II to IV heart disease or cardiac ejection fraction measurement of <50% at baseline
• Current clinical evidence of any uncontrolled cardiac arrhythmia
• Crohn's disease or ulcerative colitis
• Bone marrow dysplasia
• Moderate and severe hepatic impairment (Child-Pugh Classes B and C)
• Unmanageable fecal incontinence.
• Any condition, which in the opinion of the investigator would preclude participation in this trial (eg, history of seizure).
• Hypersensitivity to the active substances or to any excipients of radium-223 dichloride, or abiraterone acetate or enzalutamide.
• Prior therapeutic systemic radiation with any radiopharmaceutical medication for the treatment of prostate cancer, including but not limited to lutetium-177, strontium-89, samarium-153, iodine-131, rhenium-186, rhenium-188, or radium-223. Radiopharmaceutical compounds used for diagnosis purposes only are allowed.
• Prior hemibody external radiotherapy is excluded. Participants who received other types of prior external radiotherapy are allowed provided that the bone marrow function is assessed and meets the protocol requirements for Hb, ANC, and platelet count.
• Blood transfusion or erythropoietin stimulating agents 4 weeks prior to Screening and during the whole Screening period before randomization.
• Excessive intake of biotin above the recommended daily dose of 30 μg. Biotin is found in multivitamins, including prenatal multivitamins, biotin supplements, and dietary supplements for hair, skin, and nail growth at levels that may interfere with laboratory tests.
• Prior administration of an investigational therapeutic for CRPC.
• Previous (within the last 4 weeks of randomization) or concurrent participation in any interventional clinical study with investigational study drug administration.

• Minimum Eligible Age: 18 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: No

Sponsors

Bayer

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Specialist Services Medical Group

Castle Hill, New South Wales, Australia

Gosford Hospital

Gosford, New South Wales, Australia

Nepean Hospital

Kingswood, New South Wales, Australia

North West Cancer Centre

North Tamworth, New South Wales, Australia

Northern Cancer Institute

St Leonards, New South Wales, Australia

Prince of Wales Hospital NSW

Sydney, New South Wales, Australia

Illawarra Shoalhaven Local Health District

Wollongong, New South Wales, Australia

Icon Cancer Care

Brisbane, Queensland, Australia

Tasman Health Care

Southport, Queensland, Australia

The Tweed Hospital

Tugun, Queensland, Australia

Royal Adelaide Hospital

Adelaide, South Australia, Australia

Kepler Universitätsklinikum Campus III

Linz, Upper Austria, Austria

Klinik Ottakring - Wilhelminenspital

Vienna, , Austria

Fakultni nemocnice u sv. Anny

Brno, , Czechia

Krajska Zdravotní, a.s. - Nemocnice Chomutov, o.z. - Onkologické oddelení

Chomutov, , Czechia

Krajska Nemocnice Liberec

Liberec, , Czechia

Urocentrum Praha, s.r.o.

Prague, , Czechia

Všeobecná fakultní nemocnice v Praze

Prague, , Czechia

Fakultni Thomayerova Nemocnice

Prague, , Czechia

Fakultní nemocnice Bulovka

Prague, , Czechia

OBSOLETE_Docrates Klinikka

Helsinki, , Finland

Oulu University Hospital, Oulun yliopistollinen sairaala (OYS)

Oulu, , Finland

Seinäjoen keskussairaala

Seinäjoki, , Finland

Tampere University Hospital, Tampereen yliopistollinen sairaala (TAYS)

Tampere, , Finland

Hôpital Saint André - Bordeaux

Bordeaux, , France

Hôpital Morvan - Brest

Brest, , France

Centre de Lutte Contre le Cancer François Baclesse

Caen, , France

Hôpital Henri Mondor

Créteil, , France

Centre Georges Francois Leclerc Dijon

Dijon, , France

Centre Hospitalier Universitaire - Grenoble

Grenoble, , France

Institut Paoli-Calmettes - Marseille

Marseille, , France

Centre Antoine Lacassagne

Nice, , France

Institut de Cancerologie Jean Godinot

Reims, , France

Centre Eugène Marquis - Rennes Cedex

Rennes, , France

CHU Strasbourg - Hopital Hautepierre

Strasbourg, , France

Institut de Cancérologie de Lorraine - Alexis Vautrin

Vandœuvre-lès-Nancy, , France

Gustave Roussy - Departement Oncologie-Radiotherapie

Villejuif, , France

Universitätsklinikum Münster

Münster, North Rhine-Westphalia, Germany

Universitätsmedizin der Johannes Gutenberg Universität Mainz

Mainz, Rhineland-Palatinate, Germany

Hong Kong Integrated Oncology Centre (HKIOC)

Central, , Hong Kong

Pamela Youde Nethersole Eastern Hospital

Chai Wan, , Hong Kong

Prince of Wales Hospital

Hong Kong, , Hong Kong

Queen Mary Hospital

Hong Kong, , Hong Kong

Tuen Mun Hospital

TBC, , Hong Kong

Semmelweis University

Budapest, , Hungary

Jasz-Nagykun-Szolnok Varmegyei Hetenyi Geza Korhaz

Szolnok, , Hungary

Lady Davis Carmel Medical Center

Haifa, , Israel

Tel-Aviv Sourasky Medical Center

Tel Aviv, , Israel

University Hospital Of Ferrara - Oncologia Clinica

Ferrara, Emilia-Romagna, Italy

Azienda Ospedaliero Universitaria di Modena_Policlinico - Oncologia

Modena, Emilia-Romagna, Italy

Azienda Ospedaliero Universitaria Parma - SC Oncologia Medica

Parma, Emilia-Romagna, Italy

Centro di Riferimento Oncologico di Aviano - Oncologia Medica e dei Tumori Immuno-Correlati

Aviano, Friuli Venezia Giulia, Italy

Fondazione Policlinico Universitario Agostino Gemelli IRCCS - Servizio di Radioterapia Oncologica

Rome, Lazio, Italy

Ente Ospedaliero Ospedali Galliera Di Genova - Oncologia Medica

Genoa, Liguria, Italy

Istituto Europeo di Oncologia s.r.l

Milan, Lombardy, Italy

Azienda Ospedaliero-Universitaria Ss.Antonio E Biagio E C.Arrigo Alessandria_Presidio Civile - Oncologia

Alessandria, Piedmont, Italy

Azienda Provinciale Per I Servizi Sanitari_Ospedale Santa Chiara - UO Oncologia Medica

Trento, Trentino-Alto Adige, Italy

Istituto Oncologico Veneto_Padova - UOC Oncologia 1

Padua, Veneto, Italy

The Hospital of Lithuanian University of Health SciencesLUHS

Kaunas, , Lithuania

PI Klaipedos University Hospital

Klaipėda, , Lithuania

National Cancer Institute

Vilnius, , Lithuania

Vilnius University Hospital Santaros Klinikos

Vilnius, , Lithuania

Szpital Wojewodzki im. Mikolaja Kopernika w Koszalinie - Oddzial Dzienny Chemioterapii

Koszalin, , Poland

Narodowy Instytut Onkologii im. Marii Sklodowskiej-Curie

Krakow, , Poland

Scanmed SA ZOZ Gastromed

Lublin, , Poland

Szpital Grochowski im. dr.med. Rafala Masztaka

Warsaw, , Poland

Uniwersytecki Szpital Kliniczny UM we Wroclawiu

Wroclaw, , Poland

Chelyabinsk Regional Oncology Dispensary

Chelyabinsk, , Russia

National Medical Research Radiology Center

Obninsk, , Russia

National Cancer Center Singapore - Oncology Department

Singapore, , Singapore

Singapore General Hospital

Singapore, , Singapore

National Cancer Center

Goyang-si, Gyeonggido, South Korea

Seoul National University Bundang Hospital

Seongnam-si, Gyeonggido, South Korea

Seoul St. Mary's Hospital

Seoul, Seocho-Gu, South Korea

Asan Medical Center | Ophthalmology

Seoul, Seoul Teugbyeolsi, South Korea

Seoul National University Hospital

Seoul, Seoul Teugbyeolsi, South Korea

Complexo Hospitalario Universitario De Santiago | Oncologia

Santiago de Compostela, A Coruña, Spain

Hospital Universitari Son Espases | Oncologia

Palma de Mallorca, Balearic Islands, Spain

Hospital Germans Trias I Pujol | Oncologia

Badalona, Barcelona, Spain

Hospital General Universitario De Castellon | Oncologia

Castellon, Castellón, Spain

Hospital Universitario Puerta De Hierro De Majadahonda | Oncologia

Majadahonda, Madrid, Spain

Hospital Universitario Central De Asturias | Oncologia

Oviedo, Principality of Asturias, Spain

Fundacion Centro Oncologico Regional De Galicia Jose Antonio Quiroga Y Pineyro | Oncologia

A Coruña, , Spain

Hospital Universitari Vall D Hebron | Oncologia

Barcelona, , Spain

Institut Catala D'oncologia | Oncologia

Barcelona, , Spain

Hospital De La Santa Creu I Sant Pau | Oncologia

Barcelona, , Spain

Hospital Universitario Puerta Del Mar | Oncologia

Cadiz, , Spain

Hospital Universitario De Jaen | Oncologia

Jaén, , Spain

Hospital Universitario Lucus Augusti | Oncologia

Lugo, , Spain

Hospital Universitario 12 De Octubre | Oncologia

Madrid, , Spain

Hospital Universitario Virgen De La Victoria | Oncologia

Málaga, , Spain

Fundacion Instituto Valenciano De Oncologia | Oncologia

Valencia, , Spain

Kaohsiung Medical University Chung-Ho Memorial Hospital

Kaohsiung City, Kaohsiung, Taiwan

Taichung Veterans General Hospital

Taichung, , Taiwan

National Cheng Kung University Hospital

Tainan, , Taiwan

Taipei Veterans General Hospital

Taipei, , Taiwan

Chang Gung Memorial Hospital at Linkou

Taoyuan District, , Taiwan

Baskent Universitesi Seyhan Hastanesi

Adana, , Turkey (Türkiye)

Hacettepe Universitesi Tip Fakultesi

Ankara, , Turkey (Türkiye)

Ankara Yildirim Beyazit Universitesi Tip Fakültesi

Ankara, , Turkey (Türkiye)

Ankara Universitesi Tip Fakultesi Hastanesi

Ankara, , Turkey (Türkiye)

Trakya Univ. Tip Fak.

Edirne, , Turkey (Türkiye)

Gaziantep Universitesi Tip Fakultesi

Gaziantep, , Turkey (Türkiye)

Istanbul Universitesi Istanbul Tip Fakultesi Hastanesi

Istanbul, , Turkey (Türkiye)

Istanbul Egitim ve Arastirma Hastanesi

Istanbul, , Turkey (Türkiye)

Istanbul Universitesi Cerrahpasa-Cerrahpasa Tip Fakultesi

Istanbul, , Turkey (Türkiye)

TC Saglik Bakanligi Goztepe ProfDr Suleyman Yalcin Sehir Has

Istanbul, , Turkey (Türkiye)

Medipol Universitesi Tip Fakultesi

Istanbul, , Turkey (Türkiye)

Marmara University Medical Faculty | Pediatric Nephrology

Istanbul, , Turkey (Türkiye)

Ege Universitesi Tip Fakultesi Hastanesi

Izmir, , Turkey (Türkiye)

Izmir Tepecik Egitim ve Arastirma Hastanesi

Izmir, , Turkey (Türkiye)

Dokuz Eylul Universitesi Arastirma Uygulama Hastanesi

Izmir, , Turkey (Türkiye)

Izmir Ekonomi Universitesi Medikal Point Hastanesi

Izmir, , Turkey (Türkiye)

Erciyes Universitesi Tip Fakultesi

Kayseri, , Turkey (Türkiye)

Mersin Universitesi Tip Fakultesi

Mersin, , Turkey (Türkiye)

Ondokuz Mayis Universitesi Tip Fakultesi Saglik Uygulama ve Arastirma Merkezi

Samsun, , Turkey (Türkiye)

Royal Berkshire NHS Foundation Trust¦Royal Berkshire Hospital - Oncology

Reading, Berkshire, United Kingdom

NHS Greater Glasgow & Clyde | Beatson West of Scotland Cancer Centre - Clinical Research Unit

Glasgow, Scotland, United Kingdom

Countries

Australia; Austria; Czechia; Finland; France; Germany; Hong Kong; Hungary; Israel; Italy; Lithuania; Poland; Russia; Singapore; South Korea; Spain; Taiwan; Turkey (Türkiye); United Kingdom

Related Links

https://clinicaltrials.bayer.com/

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Other Identifiers

2023-505830-89-00

Identifier Type: OTHER

Identifier Source: secondary_id

2019-000476-42

Identifier Type: EUDRACT_NUMBER

Identifier Source: secondary_id

20510

Identifier Type: -

Identifier Source: org_study_id