Prophylactic Radiotherapy to Prevent Bone Complications in Patients With Metastatic Solid Cancers

NCT07540650 | Not Yet Recruiting Phase 2

• 1 other identifier: ORI2025-23
• Study Type: interventional
• Target: 90
• Locations: 1 country
• Sites: 1

Brief Summary

This is a prospective, randomized, single-center clinical trial evaluating whether early prophylactic radiotherapy to high-risk asymptomatic or minimally symptomatic bone metastases reduces the 1-year rate of skeletal-related events (SREs) in patients with metastatic solid cancers. Patients will be randomized in a 1:1 ratio to receive either standard of care systemic therapy or observation, or prophylactic radiotherapy in addition to standard of care. The primary endpoint is the 1-year rate of SREs. Secondary endpoints include adverse events, quality of life, economic burden, pain-free survival, and overall survival.

Conditions

Bone Metastases; Metastatic Solid Tumor

Keywords

prophylactic radiotherapy; early radiotherapy

Outcome Measures

Primary Outcomes (1)

• 1-year rate of skeletal-related events (SREs)

  Number of participants experiencing at least one skeletal-related event (pathological fracture, spinal cord compression, need for radiation to bone, need for surgery to bone, or tumor-related hypercalcemia) within 12 months after randomization.

  From randomization to 12 months after randomization

Secondary Outcomes (7)

• Incidence of adverse events

  Up to 12 months after randomization

• EORTC QLQ-C30 global health status score

  Baseline, 3 months, 6 months, and 12 months after randomization

• EQ-5D-5L index score

  Baseline and follow-up visits up to 12 months after randomization

• Brief Pain Inventory (BPI) pain intensity score

  Baseline and follow-up visits up to 12 months after randomization

• Pain-free survival

  From randomization to 12 months after randomization

Study Arms (2)

Prophylactic Radiotherapy + Standard of Care

EXPERIMENTAL

Participants receive prophylactic external-beam radiotherapy (25 Gy in 5 fractions) to up to five high-risk asymptomatic or minimally symptomatic bone metastases, in addition to standard of care systemic therapy or observation.

Radiation: Prophylactic External Beam Radiotherapy; Other: Standard of Care

Standard of Care

ACTIVE COMPARATOR

Participants receive standard of care systemic therapy or observation according to tumor type and clinical guidelines, without prophylactic radiotherapy.

Other: Standard of Care

Interventions

Prophylactic External Beam Radiotherapy RADIATION

External beam radiotherapy delivered to up to five high-risk asymptomatic or minimally symptomatic bone metastases at a total dose of 25 Gy in 5 fractions.

Prophylactic Radiotherapy + Standard of Care

Standard of Care OTHER

Systemic therapy or observation according to tumor type and clinical guidelines.

Prophylactic Radiotherapy + Standard of Care; Standard of Care

Eligibility Criteria

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

You may qualify if:

• Age ≥18 years
• Histologically confirmed solid malignancy
• Metastatic disease confirmed by imaging (CT, MRI, or PET-CT)
• Presence of up to five high-risk bone metastases
• High-risk bone metastases defined according to protocol criteria
• Asymptomatic or minimally symptomatic bone metastases (not requiring opioid analgesics)
• ECOG performance status 0-2
• Ability to provide written informed consent

You may not qualify if:

• Prior radiotherapy to the index bone metastases preventing safe treatment planning
• Symptomatic bone metastases requiring immediate palliative radiotherapy
• Evidence of spinal cord compression
• Bone metastases causing significant pain requiring opioid analgesics
• Oligometastatic disease suitable for radical treatment
• Leptomeningeal disease
• ECOG performance status ≥3
• Life expectancy less than 3 months
• Any condition that, in the investigator's opinion, would interfere with study participation or assessment

Sponsors & Collaborators

• Institute of Oncology Ljubljana: lead

Study Sites (1)

Institute of Oncology Ljubljana

Ljubljana, 1000, Slovenia

Location

MeSH Terms

Conditions

Neoplasm Metastasis

Interventions

Standard of Care

Condition Hierarchy (Ancestors)

Neoplastic Processes; Neoplasms; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Quality Indicators, Health Care; Quality of Health Care; Health Services Administration; Health Care Quality, Access, and Evaluation

Central Study Contacts

Eva Ćirić, MD

CONTACT

+38615879623; eciric@onko-i.si

Klavdija Korošec

CONTACT

+38631630065; kkorosec@onko-i.si

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: NONE
• Masking Details: This is an open-label study due to the nature of the intervention (radiotherapy), which does not allow blinding of participants or investigators.
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Participants are randomized in a 1:1 ratio to one of two parallel groups: 1. standard of care systemic therapy or observation, or 2. prophylactic external-beam radiotherapy in addition to standard of care systemic therapy or observation.

Study Record Dates

• First Submitted: April 2, 2026
• First Posted: April 20, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): February 1, 2029
• Study Completion (Estimated): February 1, 2029
• Last Updated: April 20, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

SL (1)