Stereotactic MRI-guided Radiation Therapy for Localized prostatE Cancer (SMILE)

March 6, 2026 updated by: Juergen Debus, University Hospital Heidelberg
As the most common carcinoma in men, prostate cancer is a significant tumor entity in oncology. In addition to the surgical approach, definitive radiotherapy is an equivalent therapy alternative in the non-metastatic primary situation. However, radiotherapy usually stretches over a period of several weeks (7 to 8 weeks) during which the patient receives irradiation on a daily basis. For this reason and for radiobiological considerations the total treatment time is increasingly shortened. It has been shown in several randomized phase III studies that shorting radiotherapy to about 4 weeks by increasing the single dose (so-called hypofractionation) is possible. Meanwhile there is also more data on extreme hypofractionation (max. 10 radiation sessions) available, however often times, extensive preparations are necessary (such as the invasive introduction of markers into the prostate). The current, prospective, non-randomized, multicentric, Phase II SMILE study is now testing whether the MRI-guided radiotherapy with a greatly shortened radiotherapy of the prostate over 5 radiation sessions is possible and safe.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
68

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

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

  • Germany
      • Heidelberg, Germany, 69120
        • University Hospital of Heidelberg, Radiation Oncology

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Histologically confirmed prostate carcinoma with tissue classification according to Gleason score and PSA
  • low- or intermediate-risk carcinoma according to d'Amico criteria or early high-risk Carcinoma (cT3a and / or GS ≤ 8 and / or PSA ≤ 20ng / ml)
  • IPSS (International Prostate Symptom Score) max. 12
  • Prostate volume <80cm³
  • Karnofsky index ≥ 70%
  • Age ≥ 18 years
  • Patient information provided and written consent
  • Ability of the patient to give consent

Exclusion Criteria:

  • Previous radiotherapy in the pelvis
  • Previous local therapy of the prostate
  • lymphogenic metastasis
  • Stage IV (distant metastases)
  • Contraindication to MRI
  • Simultaneous participation in another clinical study which could influence results of either of the respective study

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: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: MR-guided Radiotherapy (5 x 7,5 Gy)
5 x 7,5 Gy prescribed on the PTV
Radiation: MR-guided Radiotherapy
Total Dose 37,5 Gy, Single Dose 7,5 Gy, 5 Fractions applied in 1-2 weeks

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Toxicity or Discontinuation of Therapy
Time Frame: Within 1 Year

One of the the following events are counted as an Event (Number of Participants affected):

  • any urogenital or gastrointestinal grade ≥ 2 toxicity within one year after the start of RT (according to NCI CTCAE Version 5.0)
  • Discontinuation of therapy, with a connection to the study treatment
Within 1 Year

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Mortality
Time Frame: Within 1 year and within 5 years
Mortality due to study treatment or due to prostate Cancer (Number of Participants deceased)
Within 1 year and within 5 years
Number of Toxicities
Time Frame: Within 1 year and within 5 years after start of radiotherapy
Number and severity of urogenital or gastrointestinal toxicity
Within 1 year and within 5 years after start of radiotherapy
bPFS
Time Frame: from start of radiotherapy (day 1) until PSA-relapse according to Phoenix-Criteria (Prostate-specific antigen (PSA) nadir + 2 ng/mL after radiotherapy), assessed up to 5 years
biochemical progression free survival
from start of radiotherapy (day 1) until PSA-relapse according to Phoenix-Criteria (Prostate-specific antigen (PSA) nadir + 2 ng/mL after radiotherapy), assessed up to 5 years
Hormone therapy-free Survival
Time Frame: from start of radiotherapy until start of hormon treatment; maximum 3 months neoadjuvant
Hormone therapy-free Survival
from start of radiotherapy until start of hormon treatment; maximum 3 months neoadjuvant
OS
Time Frame: from start of radiotherapy (day 1) until death or censoring assessed up to 5 years
overall survival
from start of radiotherapy (day 1) until death or censoring assessed up to 5 years
Quality of life according to EORTC QLQ-C30
Time Frame: from start of radiotherapy (day 1) until end of follow-up (up to 5 years)
Quality of life according to EORTC QLQ-C30
from start of radiotherapy (day 1) until end of follow-up (up to 5 years)
Quality of life according to EORTC QLQ-PR25
Time Frame: from start of radiotherapy (day 1) until end of follow-up (up to 5 years)
Quality of life according to EORTC QLQ-PR25
from start of radiotherapy (day 1) until end of follow-up (up to 5 years)
Symptoms and Toxicity
Time Frame: from start of radiotherapy (day 1) until end of follow-up (up to 5 years)
Symptoms and Toxicity according to NCI CTCAE (Rate)
from start of radiotherapy (day 1) until end of follow-up (up to 5 years)

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University Hospital Heidelberg

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Ludwig-Maximilians - University of Munich
University Hospital, Zürich

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 (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
March 25, 2021

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 25, 2023

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 25, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
March 5, 2021

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 13, 2021

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
April 15, 2021

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
March 10, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
March 6, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
March 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • SMILE

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

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.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings