Study of Hypo-fractionated Proton Radiation for Low Risk Prostate Cancer

September 2, 2025 updated by: Proton Collaborative Group

A Phase III Prospective Randomized Trial of Standard-fractionation vs. Hypo-fractionation With Proton Radiation Therapy for Low Risk Adenocarcinoma of the Prostate

The purpose of this study is to compare the effects (good and bad) on patients with prostate cancer by comparing the standard dose of radiation therapy (44 treatments over 8½-9 weeks) with a higher daily dose of radiation (5 treatments over 1-2 weeks) to see if the effects of the treatments are similar or better.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

150

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Arizona
      • Phoenix, Arizona, United States, 85054
        • Mayo Clinic Cancer Center
    • Illinois
      • Warrenville, Illinois, United States, 60555
        • Northwestern Medicine Chicago Proton Center
    • Maryland
      • Baltimore, Maryland, United States, 21201
        • Maryland Proton Treatment Center
    • Oklahoma
      • Oklahoma City, Oklahoma, United States, 73142
        • Oklahoma Proton Center
    • Virginia
      • Hampton, Virginia, United States, 23666
        • Hampton University Proton Therapy Institute

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Histologically confirmed prostate adenocarcinoma within 365 days prior to randomization.
  • History/physical examination with digital rectal examination of the prostate and baseline toxicity assessment within 90 days prior to randomization.
  • Histological evaluation of prostate biopsy with assignment of a Gleason score to the biopsy material;Gleason score must be in the range of 2-6. > 6 cores are strongly recommended.
  • PSA values < 10 ng/ml within 90 days prior to randomization. Either done prior to biopsy or at least 21 days after prostate biopsy.
  • Clinical stages T1a-T2a N0 M0 (AJCC Criteria 7th Ed.). Staging must be done by treating investigator.
  • No pelvic lymph nodes > 1.5 cm in greatest dimension unless the enlarged lymph node is biopsied and negative.
  • Patients must be at least 18 years old.
  • ECOG performance status 0-1 (appendix I) documented within 90 days prior to randomization.
  • IPSS score <= 16.
  • Patients must give IRB approved, study specific, informed consent.
  • Patients must complete all mandatory tests listed in section 4.0 within the specified time frames.
  • Patients must be able to start treatment within 56 days of randomization.

Exclusion Criteria:

  • Previous prostate cancer surgery to include: prostatectomy, hyperthermia and cryosurgery.
  • Previous pelvic radiation for prostate cancer.
  • Androgen deprivation therapy prior to radiation is allowed. However, it is not acceptable if continued during radiation or as adjuvant therapy.
  • Active rectal diverticulitis, Crohn's disease affecting the rectum, or ulcerative colitis.
  • Prior systemic chemotherapy for prostate cancer.
  • History of proximal urethral stricture requiring dilatation.
  • Current and continuing anticoagulation with warfarin sodium (Coumadin, heparin, low-molecular weight heparin, Clopidogrel bisulfate (Plavix),or equivalent. (Unless it can be stopped to manage treatment related toxicity, to have a biopsy if needed, or for marker placement).
  • Any major medical, addictive or psychiatric illnesses which would affect the consent process, completion of treatment and/or interfere with follow-up. Consent by legal authorized representative is not permitted in this study.
  • Evidence of any other cancer within the past 5 years and < 50% probability of a 5 year survival. (Prior or concurrent diagnosis of basal cell or non-invasive squamous cell cancer of the skin is allowed).

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Other: Proton Radiation Hypofractionation
5 fractions (7.6 Gy(RBE) x 5)
Radiation: Proton Radiation Hypofractionation
Dose: 38 Gy(RBE); 7.6 GY(RBE) five days a week in 5 treatments over 1-2 weeks
Other Names:
  • Particle Therapy
Active Comparator: Proton Radiation Standard Fractionation
44 fractions (1.8 Gy(RBE) x 44)
Radiation: Proton Radiation Standard Fractionation
Dose: 79.2 GY(RBE); 1.8 GY(RBE) five days a week in 44 treatments over 8.5-9 weeks
Other Names:
  • Particle Therapy

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
To assess if hypo-fractionation will result in 2-year freedom from failure (FFF) that is non-inferior to 2-year FFF following standard fractionation. FFF will be measured by recurrence, metastasis, PSA or start of salvage therapy.
Time Frame: At 5 years post treatment completion +/- 90 days
The events for FFF will be the first occurrence of clinical failure (local recurrence, regional recurrence, or distant metastasis), biochemical failure by the Phoenix definition (PSA ≥ 2 ng/ml over the current nadir PSA),or the start of salvage therapy including androgen deprivation.
At 5 years post treatment completion +/- 90 days

Secondary Outcome Measures

Outcome Measure
Time Frame
To determine the incidence of grade 2 or greater GU and GI toxicity in each of the regimens.
Time Frame: At 6 months and 2 years post randomization
At 6 months and 2 years post randomization

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Proton Collaborative Group

Investigators

  • Study Chair: Carlos Vargas, MD, Proton Collaborative Group

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

November 1, 2010

Primary Completion (Estimated)

December 1, 2027

Study Registration Dates

First Submitted

October 27, 2010

First Submitted That Met QC Criteria

October 28, 2010

First Posted (Estimated)

October 29, 2010

Study Record Updates

Last Update Posted (Estimated)

September 4, 2025

Last Update Submitted That Met QC Criteria

September 2, 2025

Last Verified

September 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • GU002-10

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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