NCT04842890Active, not recruitingPhase 2
Phase II Study of Pencil Beam Scanning Proton Stereotactic Body Radiation Therapy for Prostate Cancer
Source: ClinicalTrials.gov · Last updated 13 Apr 2026
Brief summary (registry, in English)
This is a single arm phase II study of image-guided pencil beam scanning proton SBRT (40Gy RBE in 5 fractions delivered every other day) for patients with low- and intermediate-risk prostate cancer. The primary aim is to assess GU/GI toxicity of proton SBRT and compare this to historic outcomes associated with photon-based prostate SBRT. The primary endpoint is 2-year grade 3+ GU/GI toxicity free rate by CTCAE v5.0, which is expected to be ≥95%. Toxicity will be evaluated by the treating radiation oncologist at least once during SBRT, then following SBRT at 1, 3, 6, 12, 18, and 24 months. The treatment will be considered safe if grade 3 or higher GU/GI toxicity free rate at 2 years is \>85% (95% rate expected with a 10% non-inferiority margin). The accrual goal is 61 patients over 3 years. To ensure that unexpected significant toxicity is identified, all grade 3 or higher toxicities will be reported to the study PI and the trial will stop accruing if at any point 4 or more patients experience a grade 3 or higher toxicity after completing SBRT. This is felt to be conservative given the vast experience with photon SBRT at this dose with an expected G3+ toxicity of \~5%. Secondary objectives are to examine patient-reported urinary, gastrointestinal, sexual, and financial outcomes using IPSS, EPIC-26, and COST questionnaires at the same follow-up timepoints as above. Baseline measures of these domains will be obtained prior to treatment as well. Clinical outcomes will also be evaluated with PSA measured at each follow-up, as well as prostate MRI and biopsies at 2 years. Patients will be followed for at least 2 years to determine rates of PSA relapse, salvage treatment, development of metastases, death from prostate cancer, and overall survival. A dosimetric comparison will be performed where each patient will be planned for proton and photon SBRT to determine possible advantages of proton SBRT.
- Status (registry)
- Active, not recruiting
- Phase (registry)
- Phase 2
- Study type
- Interventional
- Enrollment
- 61 (actual)
- First submitted
- 15 Mar 2021
- Start date
- 8 Jan 2021
- Primary completion date
- 30 Jun 2026
- Lead sponsor
- The New York Proton Center
- Diseases
- Prostate cancer
- NCT number
- NCT04842890
What you commit to
- Study type: Interventional · Phase 2
- Participants enrolled: 61
- From 8 Jan 2021 to the primary completion date, 30 Jun 2026
- 1 site in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Prior prostate surgery (including cryosurgery)
- Note: Patients who underwent TURP or greenlight PVP are eligible if it was \> 12 weeks prior to the anticipated start date of SBRT
- Prior history of chronic prostatitis or urethral stricture
Other illness
- Currently active cancer(s) other than non-melanoma skin cancers. Patients are not considered to have currently active cancers if they have completed therapy and are considered by their physicians to be at \<5% risk of relapse within 2 years.
Age
- Life expectancy of \< 2 years
Who the study is looking for
- Biopsy-proven NCCN low- or intermediate-risk prostate cancer, which includes patients with:
- Gleason score ≤7 disease
- PSA ≤20 ng/ml
- Clinical T1-T2c disease
- Note: Patients who only have radiographic evidence of possible or probable T3 disease (i.e., extracapsular extension or seminal vesical invasion) will not be excluded.
- KPS ≥ 80%
- Prostate size as determined on MRI to be \< 100 cc. Prostate size can be determined on CT scan if MRI is not available.
- Male 18 years of age or older
- IPSS ≤ 20
- Patient must be a candidate for and agree to placement of intraprostatic fiducial markers and a hydrogel rectal spacer
- Patient must be available for at least 2 years of follow-up
Age in the registry: 18 years to - · Sex: Male · Does not accept healthy volunteers
Sites (1)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| The New York Proton Center Coordinator of this site? Confirm its status | New York | United States | Unknown status |
This page is information, not medical advice. Discuss any trial with your doctor.