N/A
N=86
Targeted Radiotherapy in Androgen-suppressed Prostate Cancer Patients.
Prostate Cancer · Metastasis · Toxicity Due to Radiotherapy · Circulating Tumour DNA
Bottom Line
View on ClinicalTrials.gov: NCT03644303 ↗Enrolled (actual)
86
Serious AEs
1.2%
Results posted
May 2026
Primary outcome: Primary: Median Progression-Free Survival (PFS) — 6.0 months — p=0.001
Study Design & Population
- Study type
- Interventional
- Phase
- N/A
- Interventions
- SBRT + ADT (Radiation)
- Age
- Adult, Older Adult · 18+ yrs
- Sex
- Male
- Sponsor
- Royal Marsden NHS Foundation Trust
- Primary completion
- Mar 2025
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Median Progression-Free Survival (PFS) |
6.0 | 0.001 sig |
| SECONDARY Progression-Free Survival (PFS) Events |
67; 14 | — |
| SECONDARY Progression-Free Survival (PFS) Estimates |
46.6; 30.2; 17.5 | — |
| SECONDARY Local Control Rate Following SBRT |
5; 67 | — |
| SECONDARY Median Overall Survival (OS) |
29.5 | — |
| SECONDARY Overall Survival (OS) Events |
33; 48 | — |
| SECONDARY Overall Survival (OS) Estimates |
95.0; 92.4; 75.1 | — |
| SECONDARY Median Time to Administration of Next Line of Therapy or Death |
21.4 | — |
| SECONDARY Administration of Next Line of Therapy or Death Events |
50; 31 | — |
| SECONDARY Time to Administration of Next Line of Therapy or Death |
83.8; 65.8; 49.7 | — |
| SECONDARY Health Related Quality of Life |
77; 77; 76; 76; 78; 78 | — |
| SECONDARY Number of Participants With Incidence and Severity of Treatment Induced Symptoms (RTOG) |
38; 44; 44; 55; 2; 32 | — |
| SECONDARY Number of Participants With Incidence and Severity of Treatment Induced Symptoms (CTCAE) |
51; 46; 53; 47; 2; 26 | — |
| SECONDARY Prostate Specific Antigen (PSA) Values |
7.0; 5.0; 4.5; 3.4; 6.3; 1.8 | — |
Summary
This multi-center, phase II trial will be conducted in men with castration resistant prostate cancer. The aim of the TRAP trial is to test whether a new precise radiotherapy technique called stereotactic body radiotherapy (SBRT) can slow down the growth of metastatic prostate cancer. If SBRT is effective it will represent a new treatment option in these patients, providing more prolonged control without having to resort to chemotherapy and its potentially unpleasant side effects.
In this trial, the investigators will identify men who, despite being on next generation androgen deprivation treatment (Abiraterone or Enzalutamide) have developed one or two new sites of worsening (growing) disease but the rest of their cancer is still responding to hormonal therapy. If it is the case that SBRT can successfully treat the cancer which is resistant to current treatment then the investigators hope they will be able to better control the spread of cancer in these patients for longer.
The investigators also hope that they will be able to use the tell-tale products (gene markers) that are released into the bloodstream in these patients, or identify characteristics on novel imaging such as magnetic resonance imaging (MRI) to help identify patients in the future who will benefit the most.
Eligibility Criteria
Inclusion Criteria
- Be willing and able to provide written informed consent for the trial and be ≥18 years of age on day of signing informed consent.
- Have metastatic Castration Resistant Prostate Cancer (CRPC) based on biochemical or pathological diagnosis and be on Enzalutamide or Abiraterone.
- Have had a minimum of 6 months on Enzalutamide or Abiraterone with evidence of response (PSA, radiological or symptomatic)
- Have 1 - 2 metastatic lesions progressing on imaging (CT, bone scan, MRI or other local imaging) or a clinical or imaging diagnosis of progression of a non-irradiated primary site with the remainder of their metastases currently controlled by Enzalutamide or Abiraterone.
- Have had no previous radical radiation to the index area (defined as unable to deliver SBRT doses in this protocol without taking normal tissues beyond tolerance).
- Have a Performance Status (PS) assessed using the Eastern Co-operative Oncology Group (ECOG) criteria of 0 - 1.
- Have an oligoprogressing site, including those that have developed on treatment, in bone, lymph node, prostate or lung but not in liver, brain, adrenal or other sites.
- Patients may be symptomatic in the oligoprogressing area. However, there is no urgent need to start radiotherapy.
Exclusion Criteria
- A clinical need exists to switch therapy immediately (e.g. suspicion of rapid clinical progression, urgent need for palliative radiotherapy).
- Evidence of previous invasive cancer in the last 5 years, with the exception of non-melanoma skin cancer (non-invasive malignancies such as non-muscle invasive bladder cancer are not excluded).
- There is a contra-indication to radiotherapy (e.g. inflammatory bowel disease).
- There is a contra-indication to MRI where required for radiotherapy (e.g. cardiac pacemaker, internal defibrillator, shrapnel injury or claustrophobia).
Data sourced from ClinicalTrials.gov (NCT03644303). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.