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Trial registered on ANZCTR


Registration number
ACTRN12619000365167
Ethics application status
Approved
Date submitted
1/03/2019
Date registered
7/03/2019
Date last updated
31/07/2019
Date data sharing statement initially provided
7/03/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Simethicone in Prostate Radiotherapy
Scientific title
A Randomised Trial Comparing Simethicone With No Bowel Prep In Reducing Rectal Variability During Prostate Radiotherapy.
Secondary ID [1] 297530 0
Nil known
Universal Trial Number (UTN)
U1111-1229-3333
Trial acronym
Simethicone in Prostate RadioTherapy (SPoRT)
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Prostate Cancer 311774 0
Condition category
Condition code
Cancer 310387 310387 0 0
Prostate

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Intervention:
Simethicone: An anti-flatulent medication which is a mixture of liquid dimeticones that contain finely divided silicon dioxide which acts as a defoaming agent by reducing the surface tension of mucus. This allows entrapped air bubbles to coalesce, disperse and hence aids in the expulsion of intestinal air. (MedicinesComplete)

Arm 1 will commence Simethicone 3 days before their planning CT to prepare for radiotherapy and continue this for 3 days, 1 capsule (100mg) three times a day. They can then stop taking it and restart it 3 days before radiotherapy commences (same dosing as above) and stop at the end of radiotherapy. The aim is to see if this reduces rectal volumes to allow more geographic accuracy of radiotherapy to the intended target in prostate cancer patients.
Arm 2 will be the non-intervention arm

Intervention adherence: Each patient will receive a phone call reminder 1 day prior to taking the first dose of simethicone. This will mean each patient gets two phone calls: One prior to taking the pre-planning day course of simethicone, and one prior to taking the pre-treatment course of simethicone. At each doctor review (at planning and weekly during treatment) there will be a specific form to be filled out regarding whether compliance has been achieved.
Intervention code [1] 313783 0
Treatment: Drugs
Comparator / control treatment
The "no-intervention" arm will be treated with radiotherapy to the prostate bed as usual but without medical means of bowel preparation.
Control group
Active

Outcomes
Primary outcome [1] 319290 0
Difference in mean rectal volumes in the two study groups (Are the rectal volumes smaller after simethicone) This will be measured using the 7 x weekly Cone Beam CT scans (current standard) using standard CT measuring tool. The current standard is that during radiotherapy, once a week, prostate cancer patients receive a Cone beam CT of their pelvis immediately before treatment as standard of care to check rectal size. The cone beam CT images will be transferred to the Eclipse planning system (Varian), and the rectum will be contoured in the same area as it was contoured on the initial planning CT, from 1cm below the planning target volume of the prostate or prostate bed to 7cm in slices superiorly. The rectal volumes will be extracted from Monaco for each patient.
Timepoint [1] 319290 0
Measurements will be taken during the radiotherapy treatment, at the time of the weekly cone beam CT scans: at week 1, 2, 3, 4, 5, 6 and 7 of treatment.
Secondary outcome [1] 367583 0
Difference in radiotherapy side effects in the simethicone vs no simethicone arms. (Assuming Simethicone stabilizes rectal volume, does it have potential to reduce toxicity from radiotherapy?) During the planning CT, and during weeks 4, 5 and 6 of radiotherapy patients will be asked to fill in an IPSS score questionnaire on urinary symptoms and also a proctitis score and quality of life questionnaire (EORTC QLQ C-30 and PRT23)
Timepoint [1] 367583 0
During the planning CT before their radiation therapy commences.
During weeks 4, 5 and 6 of radiotherapy.

To clarify the reason for doing these two scoring systems before treatment starts: The purpose is to establish a baseline for each patient. For example if they already have diarrhoea before treatment starts we can deduce that the radiotherapy did not cause it.
Secondary outcome [2] 367584 0
Variation in rectal volume on weekly cone beam computed tomography (does Simethicone reduce variability in rectal size?), i.e. for the same patient, does the rectal volume change less in the group on Simethicone? The cone beam CT images will be transferred to the Eclipse planning system (Varian), and the rectum will be contoured in the same area as it was contoured on the initial planning CT, usually 1cm above and below the planning target volume of the prostate bed. The rectal volumes will be extracted from Monaco for each patient.
Timepoint [2] 367584 0
Measurements will be taken during the radiotherapy treatment, at the time of the weekly cone beam CT scans: at week 1, 2, 3, 4, 5, 6 and 7 of treatment.
Secondary outcome [3] 367585 0
Volume of gas in the rectum will be evaluated to see if Simethicone reduces gas volume in the rectum.

Volume of gas in the rectum will also be contoured on the CTs, again using the Monaco planning system and this data will also be collected.
Timepoint [3] 367585 0
Measurements will be taken during the radiotherapy treatment, at the time of the weekly cone beam CT scans: at week 1, 2, 3, 4, 5, 6 and 7 of treatment.

Eligibility
Key inclusion criteria
• Patients receiving external beam radiotherapy (ERBT) to the prostate or post-prostatectomy bed +/- pelvic lymph nodes in both cases.
• Age >18 years
• Receiving 6 or more weeks of radiotherapy treatment.
• Life expectancy of at least 12 months
• Written informed consent for entry into the study.
Minimum age
18 Years
Maximum age
No limit
Gender
Males
Can healthy volunteers participate?
No
Key exclusion criteria
• History of previous surgery to the bowel.
• Inflammatory bowel disease.
• Patients taking levothyroxine - Simethicone given regularly may decrease levothyroxine absorption.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Phase 4
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Descriptive summaries of patient demographics and baseline measures will include frequency distributions for categorical variables and means and standard deviations or medians, interquartile ranges and ranges for continuous variables, depending on normality. Univariate comparisons between randomised treatment groups will be based on chi-squared or Fisher Exact tests, as appropriate, for categorical variables and independent t-tests or non-parametric Mann-Whitney U tests for continuous variables.
Linear mixed models will be used to assess the change in mean rectal volume over 7 timepoints within and between treatment groups. Results will be summarised as predicted marginal means and corresponding 95% confidence intervals. Coefficient of variation (ratio of standard deviation to the mean), based on the predicted means and standard deviations, will be calculated to show the relative variability and precision of the estimate. Homoscedasticity (equality of variances) across groups will be tested using Levene’s test which is robust to non-normality of the error distribution.

Statistical analysis will be conducted using Stata 15.0 (StataCorp LLC, College Station, Texas). All hypothesis tests will be 2-sided, and a P values of <0.05 will be considered statistically significant.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
WA
Recruitment hospital [1] 13280 0
Sir Charles Gairdner Hospital - Nedlands
Recruitment postcode(s) [1] 25846 0
6009 - Nedlands

Funding & Sponsors
Funding source category [1] 302088 0
Hospital
Name [1] 302088 0
Radiation Oncology Department ERCC, Sir Charles Gairdner Hospital
Address [1] 302088 0
Sir Charles Gairdner Hospital
Hospital Avenue
Nedlands
WA 6009
Country [1] 302088 0
Australia
Primary sponsor type
Hospital
Name
Radiation Oncology Department, Sir Charles Gairdner Hospital
Address
Radiation Oncology Department
Sir Charles Gairdner Hospital
Hospital Avenue
Nedlands
WA 6009
Country
Australia
Secondary sponsor category [1] 301906 0
None
Name [1] 301906 0
Address [1] 301906 0
Country [1] 301906 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 302767 0
Sir Charles Gairdner and Osbourne Park Health Care Group Human Research Ethics Committee
Ethics committee address [1] 302767 0
SCGOPHCG HREC
2nd Floor A Block
Hospital Avenue
NEDLANDS Western Australia 6009
Ethics committee country [1] 302767 0
Australia
Date submitted for ethics approval [1] 302767 0
Approval date [1] 302767 0
15/11/2018
Ethics approval number [1] 302767 0

Summary
Brief summary
This study will evaluate the effect of a drug called Simethicone versus no bowel preparation on rectal volume and side effects in men undergoing radiotherapy for their prostate.

Who is it for?
You may be eligible to join this study if you are male aged greater than 18 who is scheduled to receive external beam radiotherapy (ERBT) to the prostate.

Study details
Participants in this study will be randomly allocated (by chance) to one of two groups. Participants in one group take an anti-flatulent medication, called Simethicone, 3 days prior to their planning CT scan, and then throughout radiotherapy treatment. Simethicone is administered as an oral capsule three times a day. Participants in the other group will receive treatment as usual without medical means of bowel preparation.

All participants will undergo weekly Cone Beam CT scans throughout the 7 weeks of radiotherapy, in order to evaluate rectal volume and volume of gas in the rectum. They will also be asked to complete questionnaires to evaluate any radiotherapy side effects. It is hoped that this research will contribute to the further improvement of the accuracy of radiation treatment to prostate cancer patients.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 91330 0
Dr Jennifer Ward
Address 91330 0
DR JENNIFER WARD
Radiation Oncology Registrar
DD Block, Cancer Centre,
Sir Charles Gairdner Hospital
Gairdner Drive
Nedlands
WA 6008
Country 91330 0
Australia
Phone 91330 0
+61 8 64573333
Fax 91330 0
Email 91330 0
jennifer.ward@health.wa.gov.au
Contact person for public queries
Name 91331 0
Dr Jennifer Ward
Address 91331 0
DR JENNIFER WARD
Radiation Oncology Registrar
DD Block, Cancer Centre,
Sir Charles Gairdner Hospital
Gairdner Drive
Nedlands
WA 6008
Country 91331 0
Australia
Phone 91331 0
+61 8 64573333
Fax 91331 0
Email 91331 0
jennifer.ward@health.wa.gov.au
Contact person for scientific queries
Name 91332 0
Dr Jennifer Ward
Address 91332 0
DR JENNIFER WARD
Radiation Oncology Registrar
DD Block, Cancer Centre,
Sir Charles Gairdner Hospital
Gairdner Drive
Nedlands
WA 6008
Country 91332 0
Australia
Phone 91332 0
+61 8 64573333
Fax 91332 0
Email 91332 0
jennifer.ward@health.wa.gov.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
No individual patient data will not be shared. Raw line-by-line data will not be made available. Only the aggregate data will be published.
What supporting documents are/will be available?
No other documents available
Summary results
No Results