Radiation Therapy for Prostate Cancer

(ASCENDE-SBRT Trial)

Recruiting at 28 trial locations

Overseen By Wendy Parulekar

Age: 18+

Sex: Male

Trial Phase: Phase 3

Sponsor: Canadian Cancer Trials Group

Must be taking: ADT, 5-alpha reductase

Must not be taking: Anticoagulants

Disqualifiers: Prior pelvic radiotherapy, Hip prosthesis, others

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

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

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

Approved in 6 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: 8-12 weeks

710 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores whether Stereotactic Body Radiation Therapy (SBRT), a new approach to radiation therapy, can match the effectiveness of the standard method combined with a special boost for treating prostate cancer. The focus is on delivering higher doses of radiation in fewer sessions using advanced equipment. Men diagnosed with prostate cancer in the last nine months who have certain risk factors may be suitable candidates. The trial aims to determine if this quicker method is as effective and safe as the traditional approach. As a Phase 3 trial, this research represents the final step before FDA approval, offering participants the opportunity to contribute to a potentially groundbreaking treatment.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications. However, certain medications like anticoagulants may need to be stopped if they are unsafe for procedures involved in the trial. It's best to discuss your specific medications with the trial team.

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

Research has shown that Stereotactic Body Radiation Therapy (SBRT) is generally safe for treating prostate cancer. Studies have found that most patients tolerate SBRT well. For instance, one study found that 88.6% of patients who received SBRT had no disease progression after three years, indicating the treatment's effectiveness.

Some patients did experience side effects. Over five years, 27% of men receiving SBRT reported urinary problems. However, this rate was not significantly different from the 18% of patients who reported similar issues with standard radiation therapy.

Overall, SBRT is considered a safe option with manageable side effects for many patients. This treatment delivers high doses of radiation in fewer sessions, offering greater convenience. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising?

Researchers are excited about these radiation therapy options for prostate cancer due to their unique approaches. The "EBRT + Brachy Boost" combines external beam radiation therapy (EBRT) with brachytherapy, which delivers a high dose of radiation directly to the tumor, potentially improving precision and minimizing damage to surrounding tissues. On the other hand, "SBRT," or stereotactic body radiation therapy, offers a highly targeted treatment that delivers larger doses of radiation in fewer sessions, potentially leading to quicker treatment times and fewer side effects compared to conventional radiation therapies. These advancements might provide more effective and convenient alternatives to traditional prostate cancer treatments like surgery and hormone therapy.

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

Research has shown that both radiation treatments in this trial hold promise for prostate cancer. Participants in one arm will receive a combination of external beam radiation therapy (EBRT) with a brachytherapy boost, which has been linked to longer survival and a lower chance of cancer spreading compared to standard external radiation alone. In another arm, participants will receive stereotactic body radiation therapy (SBRT), which has demonstrated a high success rate, with 83.6% of patients showing no cancer progression after five years. SBRT effectively relieves symptoms without causing severe side effects and has a cure rate of about 95.7% at five years, with a relatively low risk of side effects. Both treatments are effective, offering different benefits in terms of survival, side effects, and quality of life. ^{6 7 8 9 10}

Who Is on the Research Team?

Andrew Loblaw

Principal Investigator

Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, ON, Canada

Are You a Good Fit for This Trial?

Men with prostate cancer diagnosed in the last 9 months can join this trial. They must have intermediate or high-risk factors like a Gleason score of 7-10, PSA levels of 10-20 ng/ml or higher, and certain stages of tumor growth (cT2b to cT4). Men who don't meet these specific cancer characteristics cannot participate.

Inclusion Criteria

I am taking medication for prostate enlargement or hair loss.

Participants consent must be appropriately obtained

Participants must be accessible for treatment and follow-up

Exclusion Criteria

My prostate is larger than 60cc before starting hormone therapy.

Hip prosthesis

I am on blood thinners or have a bleeding disorder.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive either Stereotactic Body Radiation Therapy (SBRT) or External Beam Radiation Therapy (EBRT) with a brachytherapy boost, combined with androgen deprivation therapy (ADT)

8-12 weeks

Follow-up

Participants are monitored for safety and effectiveness after treatment

8.6 years

What Are the Treatments Tested in This Trial?

Interventions

• Brachytherapy
• Radiation

Trial Overview The study is comparing two types of radiation therapy for prostate cancer. One group will receive SBRT, which is a high-dose radiation treatment given over fewer sessions. The other group gets usual external radiation plus brachytherapy, where radioactive material is placed inside the prostate.

How Is the Trial Designed?

Group I: SBRT Experimental Treatment 1 Intervention

Group II: EBRT + Brachy Boost Active Control 2 Interventions

Radiation is already approved in European Union, United States, Canada, Japan, China, Switzerland for the following indications:

Approved in European Union as Radiation Therapy for:

• Cancer treatment
• HPV-positive throat cancer
• Various types of tumors

Approved in United States as Radiation Therapy for:

• Cancer treatment
• HPV-positive throat cancer
• Various types of tumors

Approved in Canada as Radiation Therapy for:

• Cancer treatment
• HPV-positive throat cancer
• Various types of tumors

Approved in Japan as Radiation Therapy for:

• Cancer treatment
• HPV-positive throat cancer
• Various types of tumors

Approved in China as Radiation Therapy for:

• Cancer treatment
• HPV-positive throat cancer
• Various types of tumors

Approved in Switzerland as Radiation Therapy for:

• Cancer treatment
• HPV-positive throat cancer
• Various types of tumors

Who Is Running the Clinical Trial?

Canadian Cancer Trials Group

Lead Sponsor

Trials

135

Recruited

70,300+

NRG Oncology

Collaborator

Trials

242

Recruited

105,000+

Published Research Related to This Trial

Recent advancements in radiation therapy for prostate cancer, including dose escalation and adjuvant radiation therapy, have shown to improve overall survival, particularly in patients with pT3 disease or positive margins after surgery.

Emerging techniques like hypofractionation, stereotactic body radiation therapy, and advanced technologies such as Calypso 4D tumor tracking are promising for enhancing treatment accuracy and reducing side effects, but they require further validation in large clinical trials.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Update on radiation-based therapies for prostate cancer. Kwok, Y., Yovino, S.[2010]

Recent advancements in radiation therapy technologies, such as intensity-modulated radiation therapy and proton therapy, have allowed for higher doses of radiation to be delivered to prostate cancer while reducing damage to surrounding healthy tissues.

Randomized trials indicate that while higher radiation doses improve clinical outcomes, they also increase toxicity, highlighting the need for ongoing research to fully assess the benefits and risks of these new treatment methods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Emerging technologies in prostate cancer radiation therapy: improving the therapeutic window. Biagioli, MC., Hoffe, SE.[2017]

In a study of 9,876 men who underwent radical prostatectomy, those who received postprostatectomy radiation therapy experienced significantly higher rates of gastrointestinal (1.81 times more likely) and urinary nonincontinence adverse events (1.83 times more likely) compared to those who did not receive radiation therapy.

The timing of radiation therapy after prostatectomy did not affect the risk of these adverse events, challenging the belief that delaying radiation therapy reduces the likelihood of complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Assessing adverse events of postprostatectomy radiation therapy for prostate cancer: evaluation of outcomes in the Regione Emilia-Romagna, Italy. Showalter, TN., Hegarty, SE., Rabinowitz, C., et al.[2015]

Image-guided radiation therapies, like 3D-conformal and intensity-modulated radiation therapy, allow for the safe delivery of high doses of radiation to prostate cancer patients with manageable side effects.

Escalating radiation doses has been shown to improve biochemical disease-free survival in certain patients, while interstitial brachytherapy is effective for those with favorable cancer characteristics, highlighting the need for long-term follow-up to evaluate treatment outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Radiation therapy for prostate cancer]. Sumi, M.[2011]

In a study of 647 patients with localized prostate carcinoma treated with radiation from 1975-1989, 61% achieved clinical disease-free status, highlighting the efficacy of local tumor control in improving patient outcomes.

The research found that reducing distant metastasis (26% survival advantage) was more beneficial for overall survival than improving local tumor control (14% survival advantage), especially in patients with poorly differentiated tumors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Potential benefit of improved local tumor control in patients with prostate carcinoma. Kuban, DA., el-Mahdi, AM., Schellhammer, PF.[2019]

Radiation therapy is an effective treatment for localized prostate cancer, but there is still a significant rate of cancer persistence after treatment, indicating a need for improved methods.

New radiation techniques are being developed to enhance local control of the cancer while also aiming to preserve bladder and sexual function, and ongoing research seeks to identify which patients will benefit most from radiation therapy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[The role of radiotherapy in locally limited prostate cancer]. Herr, HW.[2006]

Recent advancements in radiation therapy for prostate cancer, such as intensity-modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT), have improved treatment precision, leading to reduced side effects and the ability to safely increase radiation doses.

Low dose rate (LDR) and high dose rate (HDR) brachytherapy are effective treatment options for localized prostate cancer, each with unique side effect profiles, while the potential benefits of proton therapy and stereotactic radiotherapy require further research through prospective trials.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Localized prostate cancer: Radiotherapeutic concepts]. Grimm, M., Wenz, F.[2018]

Radiation therapy for prostate cancer is undergoing significant advancements due to new technologies and ongoing clinical trials, which are improving treatment options.

The article reviews key findings from five studies that highlight the current effectiveness and future directions of radiation treatment for prostate cancer.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Radiation therapy for prostate cancer: An evolving treatment modality. Chen, RC.[2020]

Radiotherapy (RT) significantly improves overall survival in men with newly diagnosed prostate cancer who have a low metastatic burden, with a hazard ratio of 0.64, indicating a 36% reduction in the risk of death compared to standard care alone.

In contrast, RT does not show a survival benefit for patients with high metastatic burden, and there were no significant differences in quality of life or severe toxicity between the treatment groups, suggesting RT is safe and effective for low-burden cases.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Radiotherapy to the prostate for men with metastatic prostate cancer in the UK and Switzerland: Long-term results from the STAMPEDE randomised controlled trial. Parker, CC., James, ND., Brawley, CD., et al.[2023]

Radiation therapy, including brachytherapy and external beam radiotherapy, is an effective treatment option for newly diagnosed prostate cancer, as well as for salvage treatment and palliative care in advanced cases.

The study discusses the indications, results, and potential complications of using these radiation therapies alone or in combination with other treatments like androgen deprivation, highlighting their versatility in managing prostate cancer.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Radiation therapy for prostate cancer. Koontz, BF., Lee, WR.[2013]

A patient with prostate cancer experienced severe side effects and ultimately died 25 months after salvage radiotherapy, highlighting the potential risks for individuals with impaired DNA repair mechanisms.

The case emphasizes the need for identifying patients with increased radiosensitivity, suggesting that screening for this trait could improve radiation protection and patient safety during treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Lethal outcome after pelvic salvage radiotherapy in a patient with prostate cancer due to increased radiosensitivity : Case report and literature review. Fahrig, A., Koch, T., Lenhart, M., et al.[2018]

Patients undergoing radiation therapy for prostate cancer commonly experience symptoms such as pain, lack of energy, drowsiness, and difficulty sleeping, which generally decrease over time during treatment.

Urination problems and diarrhea show more complex patterns, indicating that these symptoms can worsen or fluctuate, highlighting the need for tailored patient support throughout the treatment process.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Trajectories and predictors of symptom occurrence, severity, and distress in prostate cancer patients undergoing radiation therapy. Knapp, K., Cooper, B., Koetters, T., et al.[2022]

In a study of 159 men with locally advanced prostate cancer treated with radiotherapy, the 5-year freedom from biochemical failure was 76%, indicating that radiotherapy is effective in managing this condition.

Using 3-dimensional conformal radiotherapy (3DCRT) with higher doses significantly improved disease-free survival (DFS) to 78% compared to 51.5% for other techniques, highlighting the importance of treatment technique and dose in improving patient outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

From two-dimensional to three-dimensional conformal radiotherapy in prostate cancer: an Indian experience. Engineer, R., Bhutani, R., Mahantshetty, U., et al.[2010]

In a study of 151 prostate cancer patients who underwent salvage radiotherapy (sRT) after radical prostatectomy, PSA monitoring during treatment did not predict therapeutic success, indicating that PSA levels alone may not be reliable indicators of treatment effectiveness.

Despite the lack of predictive value from PSA kinetics, patients generally experienced a significant prolongation in PSA doubling times after sRT, suggesting that sRT provides a therapeutic benefit for most patients, even those with higher risk factors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Salvage radiotherapy in prostate cancer patients with biochemical relapse after radical prostatectomy : Prolongation of prostate-specific antigen doubling time in patients with subsequent biochemical progression. Lohm, G., Neumann, K., Budach, V., et al.[2018]

Citations

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Comparison of Patient-reported Outcomes After External ... In this prospective comparative effectiveness study, men with localized prostate cancer who received EB-LDR reported worse urinary function after treatment than ...

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Brachytherapy boost improves survival and decreases risk ... The overall survival was positively associated with BTB compared to EBRT. The risk of developing distant metastases was reduced in the BTB group.

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A Randomized Comparison of High-Dose-Rate and Low ... In this small, randomized comparison, efficacy analysis shows no difference between LDR and HDR boost in bPFS at 5 and 8 years and confirms the excellent ...

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High-dose-rate brachytherapy lowers travel burden for men ... In this study, we compared the travel burdens of patients with prostate cancer choosing HDR-BT monotherapy versus EBRT and SBRT for treatment.

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High-Dose-Rate Brachytherapy Boost for Prostate Cancer Overall, this study demonstrated the efficacy of EBRT-boosted brachytherapy in the treatment of intermediate- and high-risk prostate cancer, with MFS rates of ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8557180/

Five-year outcomes of stereotactic body radiation therapy ... Conclusion. SBRT is a safe and effective treatment with an encouraging bPFS rate and tolerable toxicity for localized PCa patients. Patients with a Gleason ...

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Shorter radiation improves patient experience but not ... Regarding disease-free survival, 88.6% of patients in the SBRT group were free from disease progression after three years, compared to 92.1% ...

8. cancer.gov cancer.gov/news-events/cancer-currents-blog/2024/prostate-cancer-sbrt-effective-safe

SBRT Proves Effective for Some Prostate Cancers - NCI Over the 5 years of follow-up, a total of 27% of men in the SBRT group and 18% in the standard radiation therapy group reported urinary problems ...

9. sciencedirect.com sciencedirect.com/science/article/pii/S2773160X25000078

The effectiveness and safety of stereotactic body ... The results show minor, non-significant differences in survival rates compared to conventional fractionation, a type of external radiation, after two and five ...

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Long-term Outcomes of Stereotactic Body Radiotherapy for ... This cohort study of pooled individual patient data assesses long-term outcomes after stereotactic body radiotherapy for low-risk and ...