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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Date results information initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
PLENVU vs Prepkit-C Bowel Preparation for Colonoscopy
Scientific title
Comparing the efficacy and tolerability of PLENVU®, a new low-volume polyethylene glycol based bowel preparation versus standard bowel preparation with Prepkit-C® in patients undergoing routine colonoscopy.
Secondary ID [1] 294320 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Colorectal cancer 307036 0
Bowel Preparation for Colonoscopy 307037 0
Condition category
Condition code
Cancer 306137 306137 0 0
Bowel - Back passage (rectum) or large bowel (colon)
Cancer 306224 306224 0 0
Bowel - Anal

Study type
Description of intervention(s) / exposure
PLENVU is a novel, low volume (1L) polyethylene glycol based bowel preparation that has demonstrated a good safety profile and an overall bowel cleansing success in two European and one American phase 3 trials,.
Consenting patients who are to undergo routine colonoscopy will be randomised to receive PLENVU or the standard bowel preparation at Alfred Hospital using Prepkit-C.
Participants will be provided instruction sheets for taking the preparation to which they are allocated. To assess acceptance and tolerance, participants will be asked to complete a questionnaire on the day of and ahead of the procedure.
Intervention code [1] 300630 0
Treatment: Drugs
Comparator / control treatment
Prepkit-C powder sachets used for bowel preparation for colonoscopy
Control group

Primary outcome [1] 305242 0
Bowel cleanliness will be assessed using the Boston Bowel Preparation Scale as follows: Each of the 3 segments of the colon (right, including the cecum and ascending colon; transverse, including the hepatic and splenic flexures; and left, including the descending colon, sigmoid, and rectum) will be given a score from 0 to 3 defined as:
0 - unprepared colon segment with mucosa not seen because of solid stool that cannot be cleared
1 - portion of mucosa of the colon segment seen, but other areas of the colon segment not well seen because of staining, residual stool, and/or opaque liquid
2 - minor amount of residual staining, small fragments of stool and/or opaque liquid, but mucosa of colon segment seen well
3 - entire mucosa of colon segment seen well with no residual staining, small fragments of stool, or opaque liquid
Each of the 3 segment scores is then summed for a total score of 0 to 9, in which 0 is unprepared and 9 is entirely clean.
If an endoscopist aborts a procedure because of inadequate preparation, then any non-visualized proximal segments are assigned a score of 0.
Successful bowel preparation requires a minimum BBPS of 6 with a score of 2 or more in each bowel segment.
Timepoint [1] 305242 0
Day of colonoscopy procedure
Secondary outcome [1] 344604 0
Overall bowel cleanliness will be assessed using the modified Aronchick scale. The Aronchick scale is a global assessment of bowel cleansing efficacy; the modified scale assesses quality of preparation on withdrawal after cleansing. Results are categorized into 1 to 5 grades:
- Excellent: small volume of clear liquid or greater than 95% of surface seen
- Good: Large volume of clear liquid covering 5% to 25% of the surface but greater than 90% of surface seen
- Fair: Some semi-solid stool that could be suctioned or washed away but greater than 90% of surface seen
- Poor: Semi-solid stool that could not be suctioned or washed away and less than 90% of the surface seen
- Inadequate: Repeat preparation and colonoscopy needed
Timepoint [1] 344604 0
Day of colonoscopy procedure
Secondary outcome [2] 344605 0
Difference in bowel preparation quality of morning as compared with afternoon procedures will be examined according to randomised bowel preparation regimens. BBPS for each colonoscopy will be used for this analysis as per the primary endpoint.
Timepoint [2] 344605 0
Day of colonoscopy procedure
Secondary outcome [3] 344606 0
Patient compliance with the allocated bowel preparation regimen will be assessed by use of a participant questionnaire (developed for the study).
The questionnaire will also request some demographic information and information regarding medications which may interfere with colonic transit time and thus bowel preparation quality.
Timepoint [3] 344606 0
Day of and ahead of colonoscopy procedure.
Secondary outcome [4] 344607 0
Patient tolerance with and acceptance of the allocated bowel preparation regimen will be assessed by use of a participant questionnaire which has been designed specifically for this study..
Timepoint [4] 344607 0
Day of and ahead of colonoscopy procedure
Secondary outcome [5] 344892 0
Time taken to complete the colonoscopy, insertion and withdrawal times will be collected. Time data will be used from colonoscopies where additional procedures such a polyp removal were not required.
Timepoint [5] 344892 0
Time data will be recorded during the colonoscopy procedure.
Secondary outcome [6] 345013 0
Polyp detection rate/adenoma detection rate/serrated polyp detection rate
Timepoint [6] 345013 0
Polyp numbers will be recorded on the day of colonoscopy.
Polyp histology will be determined from the pathology reporting, available next day or following days after colonoscopy
Secondary outcome [7] 345015 0
Caecal and terminal ileal intubation rate
Timepoint [7] 345015 0
Recorded at completion of the colonoscopy procedure

Key inclusion criteria
Consenting adult patients (minimum age 18 years) undergoing outpatient colonoscopy for clinically accepted indications. Clinically accepted indications generally include but are not restricted to iron deficiency anaemia, surveillance of bowel polyps, colorectal cancer screening, assessment of symptoms such as abdominal pain, diarrhoea and constipation, assessment or investigation of inflammatory bowel disease.
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Exclusion criteria are conditions generally considered as exclusions to colonoscopy in normal clinical practice such as suspected bowel perforation, gastric outlet obstruction, toxic megacolon, severe colitis, pregnancy or lactation.
For additional safety, we will also exclude patients with relative contraindications such as significant renal failure (eGFR <30) and significant heart failure (New York Heart Association Class III or IV).
We will exclude patients with phenylketonuria, due to the presence of aspartame and patients with Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency given that these bowel preparation regimens contain ascorbic acid (vitamin C) which is an oxidant.
Patients with a known hypersensitivity to a constituent of Prepkit-C® or PLENVU® will also be excluded.
Patients who require an extended bowel preparation for type I diabetes mellitus, cystic fibrosis or due to having had a previous colonoscopy with inadequate bowel preparation. We will also exclude patients with previous major colonic resection as this will impact on the bowel cleaning scoring system that we are using for this study.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Patients will be screened for eligibility from their referrals to the endoscopy service and mailed the Participant Information and Consent Forms together with a letter of invitation and reply-paid envelope. Eligibility will be confirmed by a member of the research team at a follow up phone call approximately one week after patients have received the PICF. Patients who are willing to participate will be asked to return the signed PICF. On receiving the signed consent form, the research nurse will randomise participants according to a computer-generated randomisation sequence. Participants in the control group will be mailed the Prepkit-C sachets and instruction sheet/schedule for taking each dose. Participants in the intervention group will be mailed the PLENVU sachets and instruction sheet/schedule for taking each dose. Endoscopists will remain blinded to the allocation.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation by computer-generated sequence of randomisation with equal numbers of both study arms, hence equal chance of selecting either arm of the study.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Other design features
Secondary analysis will examine factors that may affect the bowel preparation such as a history of constipation, regular laxative use, use of opioid analgesia, diabetes mellitus and body mass index will also be recorded.
De-identified baseline characteristics collected by the endoscopist at time of colonoscopy will include:
- Basic demographic data: age and sex
- Prior colonic surgery
- Prior colonoscopy
- The indication for the colonoscopy
- Presence of colon cancer
Phase 3 / Phase 4
Type of endpoint(s)
Statistical methods / analysis
Approximately 300 patients will be randomized and 150 patients will be allocated to each group (two-sided alpha =5% and power =80%). An intent-to-treat analysis will be used to assess the primary outcome. The percentage of success will be assessed in each treatment group and the 95% confidence interval for the difference in success rates will be determined. Non-inferiority of the bowel preparation regimen with PLENVU will be established if the lower confidence limit for the difference in effect turns out to lie above -15%.
Secondary analyses will also be statistically evaluated. Bivariate analysis will be performed for polyp detection rates/adenoma detection ratio/serrated polyp detection rate, time to complete colonoscopy and caecal/ileal intubation rate.
Multivariate analysis using logistic regression will be conducted to assess the impact of other factors that may influence the quality of bowel preparation such as a history of constipation, regular laxative use, body mass index, use of opioid analgesia, diabetes mellitus.

Recruitment status
Stopped early
Data analysis
Data collected is being analysed
Reason for early stopping/withdrawal
Other reasons/comments
Other reasons
At an interim analysis there was a clear difference in primary end point between the 2 groups.
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 10417 0
The Alfred - Prahran
Recruitment postcode(s) [1] 22103 0
3004 - Prahran

Funding & Sponsors
Funding source category [1] 298965 0
Commercial sector/Industry
Name [1] 298965 0
Norgine Pty Ltd
Address [1] 298965 0
3/14 Rodborough Road, FRENCHS FOREST NSW 2086
Country [1] 298965 0
Primary sponsor type
The Alfred Hospital
55 Commercial Rd, Melbourne, Victoria 3004
Secondary sponsor category [1] 298247 0
Name [1] 298247 0
Address [1] 298247 0
Country [1] 298247 0

Ethics approval
Ethics application status
Ethics committee name [1] 299898 0
Alfred Hospital Ethics Committee
Ethics committee address [1] 299898 0
55 Commercial Rd, Melbourne, Victoria, 3004
Ethics committee country [1] 299898 0
Date submitted for ethics approval [1] 299898 0
Approval date [1] 299898 0
Ethics approval number [1] 299898 0

Brief summary
The study aim is to compare the efficacy and patient tolerability of PLENVU®, a new low volume bowel preparation which has demonstrated safety and overall bowel cleansing success in three European and American trials, with the current standard bowel preparation at Alfred for patients undergoing colonoscopy for clinically accepted reasons, which uses Prepkit-C®. PLENVU is a registered trademark of the Norgine Group of companies.

Who is it for?
You may be eligible for this study if you are aged 18 or over and undergoing an outpatient colonoscopy.

Study details
Participants in this study will be randomly assigned (by chance) to receive one of two bowel preparation methods, either PLENVU or Prepkit-C. Participants will use the kits before their procedure according to the instructions provided by Alfred Hospital. The effectiveness of the two kits in preparing the bowels for colonoscopy will be compared using two validated scoring methods to assess quality of bowel preparation for colonoscopy. Participants will be asked to complete a brief (10 minute) questionnaire on the day of the colonoscopy, in the waiting area, ahead of going through for their procedure. The questionnaire will ask about their experience in taking the bowel preparation they received.

The study will aim to determine whether PLENVU leads to a similar quality of bowel cleanliness as Prepkit-C and also whether patients' tolerance, acceptance and compliance is similar between the two bowel preparations.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 81914 0
A/Prof Gregor Brown
Address 81914 0
Department of Gastroenterology,
Alfred Hospital
55 Commercial Rd
Melbourne, Victoria, 3004
Country 81914 0
Phone 81914 0
+61 3 9076 8838
Fax 81914 0
+61 3 9076 2194
Email 81914 0
Contact person for public queries
Name 81915 0
A/Prof Gregor Brown
Address 81915 0
Department of Gastroenterology,
Alfred Hospital
55 Commercial Rd
Melbourne, Victoria, 3004
Country 81915 0
Phone 81915 0
+61 3 9076 8838
Fax 81915 0
+61 3 9076 2194
Email 81915 0
Contact person for scientific queries
Name 81916 0
A/Prof Gregor Brown
Address 81916 0
Department of Gastroenterology,
Alfred Hospital
55 Commercial Rd
Melbourne, Victoria, 3004
Country 81916 0
Phone 81916 0
+61 3 9076 8838
Fax 81916 0
+61 3 9076 2194
Email 81916 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
No other documents available
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary