Radium-223 for High-Volume Metastatic Hormone Sensitive Prostate Cancer

NCT07717099 | Not Yet Recruiting Phase 2

• 2 other identifiers: SC 2025-01 // 231612026-525550-11-00
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 12

Brief Summary

GUARD-QUANTUM is a prospective, phase II, single-arm, non-randomized, non-blinded, investigator-initiated study. The rationale behind studying this combination lies in the potential additive or synergistic benefits that may arise from concurrently targeting androgen receptor signaling pathways and bone metastases.

Conditions

Metastatic Hormone-Sensitive Prostate Cance

Keywords

Ra-223; Prostate cancer; hormone-sensitive; Androgen Pathway Modulation-Sensitive

Outcome Measures

Primary Outcomes (1)

• Treatment compliance

  Measured as the total number of cycles administered to each patient. Patients will be categorized in two groups, complete treatment compliance (complete ≥5 cycles of Ra223) and incomplete treatment compliance (complete \<5 cycles of Ra223). The proportion of patients in each category and their 95% confidence interval (CI) calculated by Clopper-Pearson will be given.

  Throughout the study treatment period, approximately 6 months

Secondary Outcomes (11)

• Prostate-specific antigen (PSA) response rates

  Throughout the study period, approximately 18 months

• Total alkaline phosphatase response rates

  Throughout the study period, approximately 18 months

• Radiographic progression-free survival (rPFS)

  Throughout the study period, approximately 18 months

• Time to pain progression

  Throughout the study period, approximately 18 months

• Time to next systemic antineoplastic therapy

  Throughout study period, approximately 18 months

Other Outcomes (2)

• Assessment of disease volume by novel imaging modalities (Prostate-Specific Membrane Antigen Positron Emission Tomography [PET-PSMA])

  Throughout the study period, approximately 18 months

• Biomarkers

  Tumor archival tissue sample at baseline. Blood samples at baseline, within 7 days before end of Cycle 3 (each cycle is 28 days) and at disease progression

Study Arms (1)

QUANTUM intervention

EXPERIMENTAL

Six intravenous administrations of Radium-223 chloride, in a dose of 55 kBq/kg body weight standard dose with a treatment interval between administrations of 4 weeks. Treatment with Ra223 could be prematurely discontinued in case of progression, unacceptable toxicity, withdrawal or death. Patients received backgrount therapy with ADT and darolutamide

Drug: Ra223; Drug: Darolutamide Oral Tablet; Other: Androgen Deprivation Therapy (ADT)

Interventions

Ra223 DRUG

Six intravenous administrations of Radium-223 chloride, in a dose of 55 kBq/kg body weight standard dose with a treatment interval between administrations of 4 weeks. Treatment with Ra223 could be prematurely discontinued in case of progression, unacceptable toxicity, withdrawal or death.

QUANTUM intervention

Darolutamide Oral Tablet DRUG

Darolutamide at 600 mg twice daily. Darolutamide administration will continue until progression, unacceptable toxicity, withdrawal or death, whichever comes first.

QUANTUM intervention

Androgen Deprivation Therapy (ADT) OTHER

Standard of care ADT (surgical or drug). Administration will continue until progression, unacceptable toxicity, withdrawal or death, whichever comes first.

QUANTUM intervention

Eligibility Criteria

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

You may qualify if:

• Patients must be fully informed about the study and sign the informed consent form (ICF) before any study specific assessment.
• Patients ≥18 years old.
• ECOG performance status of 0 to 2 and Charlson score ≤ 3 prior to study entry, after docetaxel.
• Patients with histologically or cytologically confirmed diagnosis of prostate adenocarcinoma.
• Patients should have received triplet therapy with ADT (luteinizing hormone releasing hormone analogue (LHRHA) for continuous treatment or previous bilateral orchidectomy), docetaxel and darolutamide as first-line therapy for mHSPC. The following conditions apply:
• Received ≥ 4 cycles of docetaxel.
• Treatment with docetaxel should be finished ≤ 12 weeks before the first planned dose of Ra223.
• Note: patients with prior therapies for locoregional disease are acceptable
• Patients should have recovered from any prior toxicity from ADT, darolutamide or docetaxel to CTCAE grade 1 or baseline levels.
• Presence of at least 4 bone metastasis on the screening bone scan, with or without lymph node and/or visceral metastases.
• Asymptomatic or mildly symptomatic (defined as short form question #3 in Brief Pain Inventory worst pain must be \< 4).
• Patients should be willing to initiate or continue bisphosphonates /denosumab, calcium and vitamin D supplements (Section 7.4.4) prior to the first dose of Ra223.
• Note: Patients must start treatment with a bone protecting agent (at doses used to reduce the incidence of skeletal related events) before the time of signing the ICF. A minimum of two doses is recommended before the first administration of Ra223. The first administration of Ra223 should be scheduled at least 6 weeks after the first administration of the bone protecting agent.
• T-score ≥ -2.5 on a DXA scan done in the past 12 months. A DXA scan performed during the screening period will be encouraged but not mandated.
• Adequate organ and bone marrow function as follows (subject must not have received any growth factor within 4 weeks or a blood transfusion within 7 days of the hematology laboratory):

You may not qualify if:

• Subjects with any of the following could not enroll in this study:
• Presence of tumor lesion in central nervous system through radiologically confirmed diagnosis.
• Patients experiencing progression during previous ADT or meeting criteria for castration resistant prostate cancer (CRPC).
• Note: Prior ADT is allowed.
• External irradiation, brachytherapy, or local treatment (including radiofrequency ablation, cryotherapy, high intensity focused ultrasound, etc.) within 4 weeks prior to the first dose of study treatment.
• Received prior chemotherapy for prostate cancer other than as part of first-line triplet therapy for mHSPC.
• Major surgery within 4 weeks prior to treatment.
• Prior hemibody external radiotherapy.
• Corticosteroids are allowed only at a dose ≤ 10 mg of prednisone (or equivalent) no matter the indication.
• Receiving abiraterone treatment as part of the first-line triplet therapy for mHSPC.
• Note: An increased risk of death and fractures was observed in a clinical study in which Ra223 was added to abiraterone acetate and prednisone/prednisolone in patients with asymptomatic or mildly symptomatic CRPC and this is the rationale to not include patients with this combination.
• Plan to receive any other antitumor therapies during this trial.
• Treatment with an investigational drug within the previous 4 weeks, or planned during the treatment period.
• Any other serious illness or medical condition such as, but not limited to:
• Any uncontrolled infection ≥ Grade 2 according to NCI-CTCAE v6.0;

Sponsors & Collaborators

• Alianza multidisciplinar para la investigación de los tumores genitourinarios -GUARD: lead
• Bayer: collaborator
• MFAR: collaborator

Study Sites (12)

Hospital Clínic de Barcelona

Barcelona, 08036, Spain

Location

Hospital Santa Creu i Sant Pau

Barcelona, 08041, Spain

Location

Complejo Hospitalario Universitario Materno-Infantil de Gran Canaria (CHUIMI)

Las Palmas de Gran Canaria, 35016, Spain

Location

Hospital Clínico San Carlos

Madrid, 28040, Spain

Location

Hospital Universitario 12 de Octubre

Madrid, 28041, Spain

Location

Hospital Universitario La Paz

Madrid, 28046, Spain

Location

Hospital Universitario HM Sanchinarro

Madrid, 28050, Spain

Location

Hospital Universitario Central de Asturias (HUCA)

Oviedo, 33011, Spain

Location

Hospital Universitario Marqués de Valdecilla

Santander, 39008, Spain

Location

Complejo Hospitalario Universitario de Santiago (CHUS)

Santiago de Compostela, 15706, Spain

Location

Instituto Valenciano de Oncología (IVO)

Valencia, 46009, Spain

Location

Hospital Clínico Universitario de Valladolid (HCUV)

Valladolid, 47003, Spain

Location

MeSH Terms

Conditions

Prostatic Neoplasms

Interventions

Radium-223; darolutamide; Androgen Antagonists

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)

Hormone Antagonists; Hormones, Hormone Substitutes, and Hormone Antagonists; Physiological Effects of Drugs; Pharmacologic Actions; Chemical Actions and Uses

Study Officials

• David Lorente, M.D., Ph.D.

  Instituto Valenciano de Oncología

  STUDY CHAIR

• Guillermo de Velasco, M.D., Ph.D.

  Hospital Universitario 12 de Octubre

  STUDY CHAIR

Central Study Contacts

GUARD Secretary

CONTACT

0034933931838; info@guardconsortium.org

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 2, 2026
• First Posted: July 21, 2026
• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): December 1, 2029
• Study Completion (Estimated): December 1, 2029
• Last Updated: July 21, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

ES (12)