Radiotherapy for Prostate Cancer

(AMPORA Trial)

Overseen By Andrew McPartlin, MBChB

Age: 18+

Sex: Male

Trial Phase: Phase 2

Sponsor: University Health Network, Toronto

Disqualifiers: Prior pelvic radiotherapy, Mets, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Approved in 4 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: 4-5 weeks

204 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests two different schedules of proton beam therapy (also known as proton therapy or PBT) for prostate cancer treatment. The researchers aim to determine if a shorter, more intense treatment schedule is as effective as a longer, daily schedule. It targets men who underwent prostate surgery more than six months ago and plan to receive radiation therapy. Participants should not have had previous radiation in the pelvis or visible cancer on imaging in the prostate area. As a Phase 2 trial, this research measures the treatment's effectiveness in an initial, smaller group, allowing participants to contribute to important advancements in prostate cancer therapy.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that proton beam therapy is generally safe for treating prostate cancer. One study found that this therapy led to fewer cases of new cancers developing in the treated area, with only 0.6% of patients experiencing this side effect. Another study demonstrated that proton therapy was as effective as traditional radiation in controlling cancer, with about 93.4% of patients showing no cancer growth after five years.

While researchers continue to study proton therapy, these results suggest that patients tolerate it well. As this trial is in Phase 2, researchers are still gathering information on its safety and effectiveness. However, current evidence indicates that proton beam therapy is a promising and relatively safe option for treating prostate cancer. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about these treatments for prostate cancer because they offer potentially more efficient and convenient radiotherapy options. Unlike traditional radiotherapy, which often requires many weeks of treatment, ultrahypofractionated radiotherapy delivers a higher dose of radiation in just five sessions over alternate days, targeting the prostate bed and possibly the pelvic lymph nodes. This could mean fewer hospital visits and less disruption to patients' lives. Meanwhile, moderately hypofractionated radiotherapy provides a balance by condensing the treatment into 20 sessions with a focus on precision and safety. Both methods aim to maintain or even improve effectiveness while reducing overall treatment time compared to conventional approaches.

What evidence suggests that this trial's treatments could be effective for prostate cancer?

This trial will compare two types of radiotherapy for prostate cancer: ultrahypofractionated radiotherapy and moderately hypofractionated radiotherapy. Research has shown that proton beam therapy (PBT) is a promising treatment for prostate cancer. One study found that PBT helps patients live longer compared to traditional external beam radiotherapy (EBRT) and resulted in fewer cases of new cancers in the treated area. Another study found that 98.9% of patients did not experience a cancer recurrence over seven years. The National Institute of Health reports that 97% of prostate cancer patients treated with proton therapy survive for at least five years. These findings suggest that PBT could be an effective option for managing prostate cancer. ^{1 2 6 7 8}

Are You a Good Fit for This Trial?

This trial is for men over 18 who've had prostate surgery at least 6 months ago and are now set to receive post-op radiation. They should be relatively active (able to walk around and take care of themselves) with a confirmed diagnosis of prostate adenocarcinoma.

Inclusion Criteria

Able to provide informed consent

I am older than 18 years.

I am fully active or can carry out light work.

Exclusion Criteria

Mets confirmed as per (if scan has been done for clinical care)

I have had radiation therapy to my pelvic area before.

I cannot undergo radiotherapy due to health reasons.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive external beam radiotherapy, either 54 Gy in 20 fractions delivered daily or 30 Gy in 5 fractions delivered on alternate days

4-5 weeks

Follow-up

Participants are monitored for safety and effectiveness after treatment, including assessment of acute and late toxicity, quality of life, and disease control

2 years

What Are the Treatments Tested in This Trial?

Interventions

• Proton Beam Therapy

Trial Overview The study compares two radiotherapy schedules for prostate cancer after surgery: one delivers a total dose daily in smaller parts over several weeks, while the other gives larger doses every other day in fewer sessions.

How Is the Trial Designed?

Group I: Arm 2: Ultrahypofractionated Radiotherapy Experimental Treatment 1 Intervention

External beam radiotherapy 30 Gy in 5 fractions to prostate bed +/- 25 Gy in 5 fractions to pelvic lymph nodes delivered on alternate days.

Group II: Arm 1: Moderately Hypofractionated Radiotherapy Experimental Treatment 1 Intervention

External beam radiotherapy 54 Gy in 20 fractions to prostate bed +/- 44 Gy in 20 fractions to pelvic lymph nodes delivered daily.

Proton Beam Therapy is already approved in United States, European Union, Japan, Canada for the following indications:

Approved in United States as Proton Beam Therapy for:

• Various cancers including prostate, breast, lung, liver, and head and neck cancers

Approved in European Union as Proton Therapy for:

• Various cancers including ocular melanoma, chordomas, chondrosarcomas, and certain pediatric cancers

Approved in Japan as Proton Beam Therapy for:

• Various cancers including prostate, liver, and ocular melanoma

Approved in Canada as Proton Therapy for:

• Various cancers including ocular melanoma and certain pediatric cancers

Who Is Running the Clinical Trial?

University Health Network, Toronto

Lead Sponsor

Trials

1,555

Recruited

526,000+

Published Research Related to This Trial

In a study of 192 prostate cancer patients treated with proton beam therapy (PBT) over a median follow-up of 1.7 years, only 5 patients experienced grade 3 toxicity, with no occurrences of grade 4 or 5 toxicity, indicating a high safety profile for this treatment.

Patient-reported outcomes showed stable urinary function post-treatment, while sexual health scores declined slightly at 1 year but did not worsen thereafter; bowel function scores also decreased but stabilized, suggesting manageable side effects associated with PBT.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Early toxicity and patient reported quality-of-life in patients receiving proton therapy for localized prostate cancer: a single institutional review of prospectively recorded outcomes. Lee, HJ., Macomber, MW., Spraker, MB., et al.[2019]

In a study of 295 men who underwent postoperative radiation therapy for prostate cancer, proton beam therapy (PBT) showed similar long-term disease control outcomes compared to intensity-modulated radiation therapy (IMRT) after a median follow-up of 59 months.

Both treatment modalities had comparable rates of biochemical failure, local failure, regional failure, distant failure, and all-cause mortality, indicating that PBT is as effective as IMRT in this setting.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparative Analysis of 5-Year Clinical Outcomes and Patterns of Failure of Proton Beam Therapy Versus Intensity Modulated Radiation therapy for Prostate Cancer in the Postoperative Setting. Barsky, AR., Carmona, R., Verma, V., et al.[2021]

Proton beam therapy (PBT) allows for higher radiation doses to be delivered to prostate cancer tissues while reducing exposure to surrounding healthy organs, making it a safer option for treatment.

Interest in PBT is growing due to improvements in treatment delivery systems and increased availability, highlighting the need for a comprehensive understanding of its effectiveness and technical aspects in treating localized prostate cancer.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Proton beam therapy for the treatment of prostate cancer. Pugh, TJ., Lee, AK.[2018]

Proton beam therapy (PBT) for prostate cancer patients receiving pelvic radiation significantly reduces acute gastrointestinal (GI) toxicity compared to intensity modulated radiation therapy (IMXT), with rates of grade 1, 2, and 3 GI toxicity at 16.4%, 2.4%, and 0%, respectively.

The study involved 85 patients with a median follow-up of 14.5 months, and while GU toxicity was higher, the results suggest that PBT may spare the small bowel, leading to less GI side effects, warranting further research.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Minimal toxicity after proton beam therapy for prostate and pelvic nodal irradiation: results from the proton collaborative group REG001-09 trial. Chuong, MD., Hartsell, W., Larson, G., et al.[2018]

In a study of 151 patients with organ-confined prostate cancer, proton beam therapy (PBT) demonstrated a low incidence of late Grade 2 or greater rectal toxicities, reported at only 2.0% after 2 years of follow-up.

The study indicates that PBT is a safe treatment option for localized prostate cancer, with minimal acute and late toxicities, suggesting it can effectively control side effects while delivering targeted radiation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Multi-institutional Phase II study of proton beam therapy for organ-confined prostate cancer focusing on the incidence of late rectal toxicities. Nihei, K., Ogino, T., Onozawa, M., et al.[2022]

Proton beam therapy (PBT) allows for higher doses of radiation to be delivered to prostate cancer tissues while minimizing damage to surrounding healthy tissues, making it a promising treatment option.

The review highlights the growing interest and advancements in PBT technology for localized prostate cancer, emphasizing the need for a deeper understanding of its application and treatment planning in radiation medicine.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Proton beam therapy for the treatment of prostate cancer. Pugh, TJ., Choi, S., Nguyen, QN., et al.[2016]

In a study of 276,880 men with localized prostate cancer, proton beam therapy (PBT) was associated with significantly better overall survival (OS) compared to photon-based external-beam radiation therapy (EBRT), with an adjusted hazard ratio of 1.72, indicating a higher risk of worse outcomes with EBRT.

PBT showed similar OS outcomes to brachytherapy (BT), particularly benefiting younger men (≤ 65 years) with low-risk disease, suggesting that PBT may be a more effective treatment option for certain patient subgroups.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Overall Survival After Treatment of Localized Prostate Cancer With Proton Beam Therapy, External-Beam Photon Therapy, or Brachytherapy. Liu, Y., Patel, SA., Jani, AB., et al.[2021]

In a study of 423 men treated with proton beam therapy (PBT) for prostate cancer, the 5.2-year follow-up showed an impressive overall survival rate of 99.8% and a disease-specific survival rate of 100%, indicating high efficacy of this treatment.

While acute toxicity was relatively low, with no severe grade ≥3 complications, there was a modest but clinically significant decrease in bowel quality of life scores after treatment, suggesting that while PBT is effective, it may still impact certain aspects of quality of life.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Proton Beam Therapy for Localized Prostate Cancer: Results from a Prospective Quality-of-Life Trial. Pugh, TJ., Choi, S., Nogueras-Gonzalaez, GM., et al.[2022]

In a study of 289 prostate cancer patients, hypofractionated proton beam therapy (PBT) showed no significant differences in acute adverse event rates or quality of life, as measured by the International Prostate Symptom Score (IPSS), compared to conventionally fractionated PBT.

The study evaluated patients treated with different doses (2.0, 2.5, and 3.0 Gy RBE per fraction) and found that factors like diabetes, age, and androgen deprivation therapy did not influence the IPSS outcomes, suggesting that hypofractionated PBT is a safe option without increased toxicity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Acute toxicity and patient-reported symptom score after conventional versus moderately hypofractionated proton therapy for prostate cancer. Iizumi, T., Ishikawa, H., Sekino, Y., et al.[2022]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC7914293/

Overall Survival After Treatment of Localized Prostate Cancer ... PBT was associated with a significant overall survival benefit compared to EBRT and had a similar performance as BT.

2. sciencedirect.com sciencedirect.com/science/article/pii/S2331518023000136

Case-Matched Outcomes of Proton Beam and Intensity ... However, in an unmatched analysis, the PBT arm had significantly fewer incidences of secondary cancers within the irradiated field (0.6%, 95% CI: 0.0%-3.1% ...

3. floridaproton.org floridaproton.org/blog-spot/survival-rates-prostate-cancer

Survival rates for prostate cancer treated with proton therapy The National Institute of Health indicates a 97%, five-year survival rate for men diagnosed with prostate cancer.

4. academic.oup.com academic.oup.com/jrr/article/66/1/39/7954234

Real-world comparative outcomes and toxicities after ... After matching analysis, 94 patients were assigned to both groups, and the PBT group showed significantly higher 7-year bRFS and DFS rates: 98.9 ...

5. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9009454/

Long-term Clinical Outcomes in Favorable Risk Prostate ... Long-term outcomes from the ProtecT randomized, controlled trial show that RT and RP both decrease the risk of disease progression and distant metastasis ...

6. ascopost.com ascopost.com/issues/april-25-2025/proton-therapy-and-intensity-modulated-radiation-therapy-for-localized-prostate-cancer/

Proton Therapy and Intensity-Modulated Radiation ... Both treatments demonstrated excellent tumor control, with progression-free survival rates at 5 years of 93.7% (IMRT) and 93.4% (proton therapy) ...

7. cancer.gov cancer.gov/news-events/cancer-currents-blog/2020/proton-therapy-safety-versus-traditional-radiation

Is Proton Therapy Safer than Traditional Radiation? - NCI After 3 years, 46% of patients in the proton therapy group and 49% of those in the traditional radiation therapy group were cancer free. Fifty- ...

8. jamanetwork.com jamanetwork.com/journals/jamanetworkopen/fullarticle/2791568

Proton Beam Therapy Use Among Patients With Newly ... This cross-sectional study assesses the changes in the use of proton beam radiotherapy in the treatment of cancers in the US over time.