Ignite Creation Date:
2026-03-26 @ 3:18 PM
Ignite Modification Date:
2026-03-31 @ 1:27 PM
Study NCT ID:
NCT07354594
Status:
NOT_YET_RECRUITING
Last Update Posted:
2026-01-21
First Post:
2025-11-17
Is NOT Gene Therapy:
True
Has Adverse Events:
False
Brief Title:
External Beam and Radioligand Radiotherapy for mCRPC
Sponsor:
Centre hospitalier de l'Université de Montréal (CHUM)
Organization:
Study Overview
Official Title:
Adaptive External Beam and Radioligand Radiotherapy for MEtaSTatic Castration Resistant Prostate Cancer (ARREST): a Phase II Registry-based RCT
Status:
NOT_YET_RECRUITING
Status Verified Date:
2026-01
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
ARREST
Brief Summary:
Introduction 177Lu-PSMA radioligand therapy (RLT) is an emerging option for metastatic castration-resistant prostate cancer (mCRPC). However, up to half of patients fail to show meaningful clinical benefit with this therapy. A dual-modality strategy seeks to increase dose via complementary external beam radiotherapy (EBRT) in underdosed tumor regions. We hypothesize that by combining both modalities (EBRT and RLT) in an hybrid, adaptive approach, we can safely improve skeletal related events when compared to standard-of-care (SOC) 177Lu-PSMA alone.
Methodology Adaptive EBRT and RLT for mCRPC (ARREST) is a pragmatic registry-based phase 2, multi-center randomized controlled trial within the PERa prospective cohort (NCT03378856) planned to activate in 2025. Patients who are receiving SOC 177Lu-PSMA with targetable metastatic burden identified on imaging suitable for EBRT will be eligible. One hundred and thirty eligible patients will be randomized 1:1 to receive either SOC 177Lu-PSMA therapy alone (maximum 6 cycles) or to combined 177Lu-PSMA plus EBRT boost. Patients in the experimental arm will undergo FDG-PET at study entry and SPECT-CT after each cycle of radioligand therapy. Lesions selected for EBRT boost will be selected based on a set of criteria that include estimated suboptimal dose absorbed from 177LuPSMA, lesions demonstrating low PSMA but high FDG update, symptomatic lesions, and those at high risk for skeletal-related events. Selected lesions will receive single-fraction EBRT. Dose prescribed will range from 6-12 Gy with the ideal goal of a combined total biological effective dose of ≥75 Gy (α/β = 1.4) with priority to dose limits for organs at risk. A maximum treatment time of 60 minutes is permitted for each EBRT boost treatment. Patients in the experimental arm that achieve complete response measured by 177Lu-SPECT-CT and PSA will pause ARREST and resume at progression. The primary endpoint is skeletal related events at 1 year. Secondary objectives include overal survival, 177Lu-SPECT-CT and PSA response, toxicity, and quality of life. The sample size is designed to detect a 12 month imporvement in the rate of skeletal related events with a HR 1.6, two-sided alpha of 0.1 and 80% power.
Conclusion ARREST is hypothesized to safely optimize tumor dose, offering a personalized hybrid approach that may lead to improved patient outcomes. In addition, this study will permit further understanding of these two distinct radiation delivery methods and their effect on tissues, thereby refining the relative biological effectiveness model for more precise treatment planning.
Methodology Adaptive EBRT and RLT for mCRPC (ARREST) is a pragmatic registry-based phase 2, multi-center randomized controlled trial within the PERa prospective cohort (NCT03378856) planned to activate in 2025. Patients who are receiving SOC 177Lu-PSMA with targetable metastatic burden identified on imaging suitable for EBRT will be eligible. One hundred and thirty eligible patients will be randomized 1:1 to receive either SOC 177Lu-PSMA therapy alone (maximum 6 cycles) or to combined 177Lu-PSMA plus EBRT boost. Patients in the experimental arm will undergo FDG-PET at study entry and SPECT-CT after each cycle of radioligand therapy. Lesions selected for EBRT boost will be selected based on a set of criteria that include estimated suboptimal dose absorbed from 177LuPSMA, lesions demonstrating low PSMA but high FDG update, symptomatic lesions, and those at high risk for skeletal-related events. Selected lesions will receive single-fraction EBRT. Dose prescribed will range from 6-12 Gy with the ideal goal of a combined total biological effective dose of ≥75 Gy (α/β = 1.4) with priority to dose limits for organs at risk. A maximum treatment time of 60 minutes is permitted for each EBRT boost treatment. Patients in the experimental arm that achieve complete response measured by 177Lu-SPECT-CT and PSA will pause ARREST and resume at progression. The primary endpoint is skeletal related events at 1 year. Secondary objectives include overal survival, 177Lu-SPECT-CT and PSA response, toxicity, and quality of life. The sample size is designed to detect a 12 month imporvement in the rate of skeletal related events with a HR 1.6, two-sided alpha of 0.1 and 80% power.
Conclusion ARREST is hypothesized to safely optimize tumor dose, offering a personalized hybrid approach that may lead to improved patient outcomes. In addition, this study will permit further understanding of these two distinct radiation delivery methods and their effect on tissues, thereby refining the relative biological effectiveness model for more precise treatment planning.
Detailed Description:
None
Study Oversight
Has Oversight DMC:
True
Is a FDA Regulated Drug?:
False
Is a FDA Regulated Device?:
False
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?: