Reduced-Dose SABR for Prostate Cancer

(POTEN-C Trial)

Recruiting at7 trial locations

Age: 18+

Sex: Male

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 2

Waitlist Available

Sponsor: University of Texas Southwestern Medical Center

No Placebo Group

Prior Safety Data

Trial Summary

What is the purpose of this trial?

Reduction of dose to or 'sparing' of neurovascular structures during stereotactic ablative body radiotherapy (SAbR) for localized prostate cancer will improve retention of sexual potency, while retaining excellent oncologic control and other secondary health-related quality of life (HRQOL) endpoints. Primary Objectives: • To compare the decline in patient health-related quality of life (HRQOL) instrument-defined erectile dysfunction following stereotactic ablative body radiotherapy (SAbR) with or without neurovascular sparing Secondary Objectives: * Assess acute (within 3 months of treatment) and chronic (\>3 months after treatment) SAbR related GU and GI toxicities, as well as serial impact on HRQOL metrics over time * Assess biochemical progression free survival, local recurrence, distant recurrence, and survival * Evaluate simplified 'practical' secondary HRQOL sexual potency endpoints that can be compared to prior literature. Exploratory Objectives: * Evaluate feasibility of MRI BOLD/TOLD to be integrated as hypoxia monitoring sequences to standard already planned diagnostic and/or treatment planning MRI on the study in five patient pilot. * Evaluate quality of spacer placement and its effect on dose to neurovascular structures * Evaluate rate local recurrence in the area of sparing adjacent to the neurovascular elements by biopsy in those with biochemical progression.

Research Team

Eligibility Criteria

Men over 18 with localized prostate cancer, good performance status, and a desire to retain sexual function. They must have a PSA ≤20 ng/ml, prostate volume ≤80 grams without severe urinary symptoms or prior treatments for prostate cancer. Participants need an adequate testosterone level and no evidence of metastatic disease.

Inclusion Criteria

My prostate cancer has a Gleason score of 7 or less.

EPIC sexual domain composite score 60-100

I am 18 years old or older.

Exclusion Criteria

My MRI shows disease very close to major nerves and blood vessels.

History of significant psychiatric illness

More than half of my biopsy samples tested positive for cancer.

Treatment Details

Interventions

• 30Gy (Gray) planning target volume (PTV) (Radiation)

Trial Overview The trial is testing whether sparing neurovascular structures during stereotactic ablative body radiotherapy (SAbR) for localized prostate cancer helps maintain erectile function better than standard SAbR, while still providing effective cancer control.

Participant Groups

Group I: SAbR WITH Neurovascular sparing Experimental Treatment 1 Intervention

* GTV represents MR defined dominant radiographic disease, if identifiable. * CTV encompasses the full prostate. At physician's discretion, the insertion of the seminal vesicle upon the prostate on slices containing prostate may be included. * PTV1_30Gy represents a 3mm expansion on the CTV, excluding the neurovascular structures on the side to be spared (left or right). PTV1 will receive 6 Gy per fraction for 5 fractions (30 Gy). * PTV2_SAbR40Gy OR PTV2_SAbR45Gy will be generated by subtracting a 5mm expansion around the neurovascular elements to be spared (at least one side, left or right) from PTV1. These neurovascular structures consist of the neurovascular bundle, penile bulb, and internal pudendal arteries (see 4.1.5.2.16). PTV2 will receive 8-9 Gy per fraction for 5 fractions (40-45 Gy).

Group II: SAbR WITHOUT Neurovascular sparing Active Control 1 Intervention

* GTV represents MR defined dominant radiographic disease, if identifiable. * CTV encompasses the full prostate. At physician's discretion, the insertion of the seminal vesicle upon the prostate on slices containing prostate may be included. * PTV1_30Gy will not be used or created on this arm * PTV2_SAbR40Gy OR PTV2_SAbR45Gy will be generated by a 3mm expansion on the CTV. PTV2_SAbR will receive 8-9 Gy per fraction for 5 fractions (40-45 Gy).

Who Is Running the Clinical Trial?

University of Texas Southwestern Medical Center

Lead Sponsor

Trials

1,102

Recruited

1,077,000+

Daniel K. Podolsky

University of Texas Southwestern Medical Center

Chief Executive Officer since 2008

MD from Harvard Medical School

Robert L. Bass

University of Texas Southwestern Medical Center

Chief Medical Officer since 2019

MD from University of Texas Southwestern Medical School

Boston Scientific Corporation

Industry Sponsor

Trials

758

Recruited

867,000+

Michael F. Mahoney

Boston Scientific Corporation

Chief Executive Officer since 2016

MBA from Wake Forest University, BBA in Finance from the University of Iowa

Kenneth Stein

Boston Scientific Corporation

Chief Medical Officer since 2020

MD from Harvard Medical School, MMSc in Clinical Investigation from Harvard-MIT Division of Health Sciences and Technology