An interventional study of High-Intermediate Risk Patients-cohort 1 and High Risk or Very High-Risk Patients-cohort 1 in Prostate Cancer, sponsored by London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's. Active, not recruiting at 2 sites in Canada. Open to male participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-05.
Sponsored by London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's · Not applicable, Interventional, and Treatment
This study is a prospective Phase I/II protocol enrolling men with either high intermediate-risk or high-risk or very high-risk prostate cancer. All men will have PSMA Targeted PET (using the PSMA targeting ligand PSMA 1007) and multiparametric magnetic resonance imaging (mpMRI) for delineation of intra-prostatic foci of cancer and any involved regional lymph nodes based on high SUV uptake on PET or mpMRI (T2W, DWI/ADC, DCE) appearance suspicious for cancer. Tumour delineation will be performed by fusing the PSMA PET and mpMRI with planning CT simulation images. Fiducial marker implantation for treatment guidance will be mandatory but use of other organs at risk protection strategies (i.e. GU Loc, Space-OAR) will be allowed but not mandatory. Patients will be treated with image-guided SBRT using the fiducial markers for intra-fraction motion management. Dose escalation to imaging defined targets (intra-prostatic and involved nodes on PSMA PET + MRI) will be accomplished through a simultaneous boost technique. Maintaining dose to organs at risk will take precedence over boost dose targets (targeted maximum dose of 50Gy/5 fractions to imaging defined prostatic lesion; 35Gy/5 fractions to imaging defined involved nodes).
Cohort extension: We hypothesize that integration of neoadjuvant androgen deprivation therapy will provide for pretreatment cancer downstaging and will allow us to achieve higher target doses to the imaging defined DILs than currently achieve. Additionally, we plan to include a novel sodium MRI protocol into the baseline imaging to compare DIL volumes delineated by this modality to those by mpMRI and PSMA PET and to characterize changes in sodium MRI in response to ADT alone and subsequent radiotherapy
6,370 studies on the registry are indexed under Prostatic Neoplasms; 1,400 are open to participants now.
This study's planned enrollment of 50 is below the median of 58 across 4,822 interventional studies indexed under Prostatic Neoplasms.
Browse Prostatic Neoplasms studies →London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's is the lead sponsor of 309 studies on the registry; 126 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Men with high intermediate to very high risk prostate cancer
Radiation: High-Intermediate Risk Patients-cohort 1 · Radiation: High Risk or Very High-Risk Patients-cohort 1 · Radiation: High-Intermediate Risk Patients-cohort 2 · Radiation: High Risk or Very High-Risk Patients-cohort 2
Patients will receive 35Gy/5 fractions to the whole prostate (25 Gy to proximal Seminal Vesicles) with a simultaneous boost to PET/MRI defined intra-prostatic foci to a target maximum dose of 50Gy/5 fractions. Six months of androgen deprivation therapy will commence with the end of radiotherapy (concurrent plus adjuvant)
Patients will receive 35Gy/5 fractions to the whole prostate (25Gy to whole Seminal Vesicles) with a simultaneous boost to PET/MRI defined intra-prostatic foci to a target maximum dose of 50Gy/5 fractions. Pelvic lymph nodes will receive 25Gy/5 fractions synchronous with prostate treatment with a simultaneous boost to imaging involved nodes to a maximum of 35Gy/5 fractions. Eighteen months of androgen deprivation therapy will commence with the end of radiotherapy (concurrent plus adjuvant)
Patients will receive 35Gy/5 fractions to the whole prostate (25 Gy to proximal Seminal Vesicles) with a simultaneous boost to PET/MRI defined intra-prostatic foci to a target maximum dose of 50Gy/5 fractions. Androgen deprivation therapy will commence 3 months before radiotherapy (concurrent plus adjuvant) and will continue for a total of 6 months.
Patients will receive 35Gy/5 fractions to the whole prostate (25 Gy to proximal Seminal Vesicles) with a simultaneous boost to PET/MRI defined intra-prostatic foci to a target maximum dose of 50Gy/5 fractions. Androgen deprivation therapy will commence 3 months before radiotherapy (concurrent plus adjuvant) and will continue for a total of 18 months.
6-month Toxicity
6-month gastrointestinal (GI) and genitourinary (GU) toxicity using the Common Terminology Criteria for Adverse Events version 5.0 (CTCAE v5.0).
Time frame: 6-months
6-week Toxicity
6-week gastrointestinal (GI) and genitourinary (GU) toxicity using the Common Terminology Criteria for Adverse Events version 5.0 (CTCAE v5.0).
Time frame: 6-weeks
Expansion cohort: Median minimum dose to dominant intra-prostatic lesion
Expansion cohort: Median minimum dose to dominant intra-prostatic lesion
Time frame: 6-months
Quality of Life measured by the Expanded Prostate Cancer Index Composite (EPIC-26) questionnaires
Quality of life measured by the Expanded Prostate Cancer Index Composite (EPIC-26) questionnaires.
Time frame: 5 years
Disease Free Survival
Five-year disease-free survival (DFS) as a composite of biochemical control, patient death or development of clinical metastases or institution of salvage ADT.
Time frame: 5 years
Translational Endpoint 1
Serial PSMA PET/MRI images will be collected at baseline, 6 months and 2 years to characterize the imaging response of prostate cancer to treatment and potentially identify imaging biomarkers (including pharmacokinetic, radiomic and quantitative PET and mpMRI metrics) that predict for five-year DFS
Time frame: 24 months
Translational Endpoint 2
Baseline collection of diagnostic tissue biopsy samples and serial collection of blood and urine over multiple time points (baseline, 6 months, 1 year, 2 years post radiotherapy) for correlative biologic biomarker analyses with imaging changes and disease-free survival and toxicity post treatment
Time frame: 24 Months
Translational Endpoint 3
A prostate biopsy at baseline and 2 years will allow for correlation of histopathology with PSMA PET/MRI images. Specifically, we will investigate biopsy correlations with pre-treatment PSMA PET/MRI images and whether a negative PSMA PET/MRI is correlated with a negative 2-year post treatment biopsy (shown to correlate with long term disease control
Time frame: 2 years
Translational Endpoint 4
Examine novel clinical prognostic biomarkers (i.e. percentage of Gleason Pattern 4 on biopsy, 4- year PSA response rate) and their correlation with imaging findings and 5-year Disease Free Survival
Time frame: 5 years
Translational Endpoint- Expansion cohort
Characterize intra-prostatic foci on pre, post 3-month ADT and 6 months post radiotherapy on PSMA PET/MRI + sodium MRI imaging
Time frame: 6 months
Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's