Colonic PolypsRIGHT-CLEANNCT07813013
Right Colon Enema to Improve Bowel Preparation Quality During Colonoscopy
A study testing Sodium phosphate enema and Water instillation in people with Colonic Polyps and Colorectal Neoplasms, run by Westmead Hospital at 2 sites in Australia.
Trial summary
Colonoscopy is a test that lets doctors look inside the large bowel to find and remove growths called polyps, which can develop into bowel cancer. Before the test, people take a bowel preparation to empty the bowel. Even so, the right side of the bowel is often not clean enough, and polyps there can be missed. Read more about this study
- Who is it for?
- Ages 18 to 85 yearsHealthy volunteers can take part
- Conditions the study is for
- Colonic Polyps, Colorectal Neoplasms, Colonoscopy
- What is being tested?
- Sodium phosphate enema and Water instillation
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 320 participants
- Where
- 2 sitesAustralia
- Study dates
- 1 Nov 2026to 1 Nov 2028
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 85 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Age 18 to 85 years
- Undergoing elective full colonoscopy for any indication
- Successful caecal intubation achieved during the procedure, confirmed prior to randomisation
- Able to provide written informed consent
Who cannot join
- Emergency colonoscopy
- Known inflammatory bowel disease with active colitis in the examined segment
- Familial polyposis syndromes
- Prior major right hemicolectomy or altered anatomy preventing standard right colon assessment
- Known obstructing colorectal malignancy precluding safe progression or adequate examination
- Pregnancy
Show all 9Show fewer
- Renal failure (eGFR less than 30 mL/min)
- Previous sodium phosphate enema within the preceding 24 hours
- Contraindication to sodium phosphate administration as determined by the treating endoscopist
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Australia2 sites
Auburn Hospital
Auburn, New South Wales, 2144
Nicholas G Burgess, MBChB,FRACP, +61 2 9845 5881, Nicholas.Burgess@health.nsw.gov.au
Westmead Hospital
Westmead, New South Wales, 2145
Nicholas G Burgess, MBChB,FRACP, +61 2 9845 5881, Nicholas.Burgess@health.nsw.gov.au
Mayan Eitan, M.D, +61 2 9845 5881, mayania9@gmail.com
About this study
Official title: RIGHT-CLEAN Trial: A Multi-centre Randomised Controlled Trial of Intra-procedural Right Colon Enema Versus no Enema to Improve Total Colonic Bowel Preparation at Colonoscopy.
Colonoscopy is a test that lets doctors look inside the large bowel to find and remove growths called polyps, which can develop into bowel cancer. Before the test, people take a bowel preparation to empty the bowel. Even so, the right side of the bowel is often not clean enough, and polyps there can be missed.
This study is testing whether giving an enema (a small amount of fluid passed into the bowel) during the colonoscopy makes the right side of the bowel cleaner. Participants having a routine colonoscopy at Westmead Hospital or Auburn Hospital will be assigned by chance to either receive the enema during the procedure or to have their colonoscopy in the usual way. Neither group takes any extra preparation at home.
The researchers will compare how clean the right side of the bowel is in each group, using a standard scoring system, and will also look at how many polyps are found. The aim is to find out whether this simple step improves the quality of colonoscopy.
Read the detailed description
Adequate mucosal visualisation in the right colon remains a limitation of colonoscopy despite standard oral bowel preparation, and residual debris in the caecum and ascending colon is associated with reduced adenoma detection and shortened surveillance intervals.
RIGHT-CLEAN is an investigator-initiated, multi-centre, randomised controlled trial conducted at Westmead Hospital and Auburn Hospital within Western Sydney Local Health District. Adults undergoing colonoscopy for [indication] will be randomised [1:1] to intraprocedural right colon enema or to standard colonoscopy without enema. Randomisation will be [method, stratified by site].
The primary outcome is [right-sided Boston Bowel Preparation Scale segment score]. Secondary outcomes include [adenoma detection rate, caecal intubation and withdrawal times, need for additional washing, and participant-reported tolerability]. Assessment of cleanliness will be performed [by blinded assessors / from recorded still images]. A sample size of [n] participants provides [x]% power to detect [effect size] at a two-sided alpha of 0.05.
All participants will provide written informed consent. No investigational drug or device is used; the enema comprises [water/saline] administered through the colonoscope during the procedure.
- Being tested
- Sodium phosphate enema, Water instillation
- Keywords
- Right Colon, Enema, Boston Bowel Preparation Scale, Adenoma Detection Rate, Bowel Preparation, Colonosocpy, Colon Polyps
- Medical subject headings
- Colonic Polyps, Colorectal Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Sodium phosphate enemaDrug
Also called Fleet enema, Monobasic sodium phosphate monohydrate / dibasic sodium phosphate heptahydrate
A single Fleet sodium phosphate enema (monobasic sodium phosphate monohydrate 19 g and dibasic sodium phosphate heptahydrate 7 g in 118 mL of saline) is administered once, intra-procedurally, into the right colon through the colonoscope working channel after confirmed caecal intubation. The enema nozzle is aligned with the working channel for delivery. The volume instilled is recorded and is not counted towards intra-procedural water-jet lavage. No further doses are given.
Water instillationOther
Immediately after confirmed caecal intubation and randomisation, with the colonoscope tip in the right colon, 100 mL of water is instilled into the right colon through the colonoscope working channel using a syringe. All subsequent steps are identical to the intervention arm: the right colon is refilled to the hepatic flexure using the foot-pump water jet, the fluid is not suctioned, the right lower quadrant is agitated by manual percussion, and the lumen is re-insufflated with CO2 before the scope is returned to the caecum for withdrawal.
| Study group | Role | What they receive |
|---|---|---|
| Intra-procedural right colon Fleet enema | Experimental | Immediately after confirmed caecal intubation and randomisation, with the colonoscope tip in the right colon, a Fleet sodium phosphate enema is instilled into the right colon through the colonoscope working channel. The right colon is then refilled to the hepatic flexure using the foot-pump water jet. The fluid is not suctioned; the right lower quadrant is agitated by manual percussion. The lumen is re-insufflated with CO2 and the scope returned to the caecum before withdrawal begins, allowing the instilled solution and mobilised faecal residue to be carried distally through the transverse and left colon. Receives: Drug: Sodium phosphate enema |
| Water control | Placebo comparator | Colonoscopy lets doctors look inside the large bowel to find and remove growths called polyps. Before the test, people take a bowel preparation to empty the bowel, but the right side of the bowel is often still not clean enough, and polyps there can be missed.
This study is testing whether a small enema given through the colonoscope into the right side of the bowel, during the procedure, makes the whole bowel cleaner. Once the camera reaches the far end of the bowel, participants are assigned by chance to receive either the enema or the same volume of water. Everything else about the procedure is the same in both groups, and no extra preparation is taken at home.
The recordings of each procedure are reviewed by independent experts who do not know which group the participant was in, and who score how clean each part of the bowel was. The researchers will also compare how many polyps were found in each group. Receives: Other: Water instillation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Final total Boston Bowel Preparation Scale (BBPS) score on blinded external image and video review
Sum of the segmental BBPS scores for the right, transverse and left colon (range 0-9, higher scores indicate better cleansing), determined by external expert reviewers masked to allocation from de-identified images and video of the withdrawal phase.
Measured: During colonoscopy withdrawal (single procedure)
Secondary outcomes (16)
Segmental Boston Bowel Preparation Scale scores on blinded external image and video review
BBPS score for each colonic segment (right, transverse and left colon), each scored 0-3, determined by external expert reviewers masked to allocation from de-identified images and video of the withdrawal phase.
Measured: During colonoscopy withdrawal (single procedure)
Proportion of participants achieving adequate bowel preparation
Proportion of participants with a total BBPS of 6 or more with each segmental score of 2 or more, on blinded external video review.
Measured: During colonoscopy withdrawal (single procedure)
Adenoma detection rate
Proportion of participants with at least one histologically confirmed conventional adenoma in any colonic segment.
Measured: From colonoscopy until histopathology results are available, up to 4 weeks
Proximal adenoma detection rate
Proportion of participants with at least one histologically confirmed conventional adenoma proximal to the splenic flexure.
Measured: From colonoscopy until histopathology results are available, up to 4 weeks
Sessile serrated lesion detection rate, overall
Proportion of participants with at least one histologically confirmed sessile serrated lesion in any segment
Measured: From colonoscopy until histopathology results are available, up to 4 weeks
Sessile serrated lesion detection rate, proximal
Proportion of participants with at least one histologically confirmed sessile serrated lesion proximal to the splenic flexure.
Measured: From colonoscopy until histopathology results are available, up to 4 weeks
Polyp detection rate
Proportion of participants with at least one polyp of any histology detected per colonoscopy.
Measured: From colonoscopy until histopathology results are available, up to 4 weeks
Operator-recorded total BBPS compared with blinded external video review
Total BBPS recorded by the proceduralist at the end of the examination, compared with the corresponding scores from blinded external video review.
Measured: During colonoscopy (single procedure)
Operator-recorded Right Colon BBPS at first inspection compared with blinded external video review
Right colon BBPS recorded by the proceduralist at first inspection after caecal intubation compared with the corresponding scores from blinded external video review.
Measured: During colonoscopy (single procedure)
Intra-procedural water volume
Total volume of water used during the examination, calculated as the filled water-jet bottle volume minus the residual volume, recorded separately from the volume of instilled study agent
Measured: During colonoscopy (single procedure)
Adenomas per colonoscopy
Proportion of participants with at least adenomatous polyp; mean number of adenomas per colonoscopy.
Measured: From colonoscopy until histopathology results are available, up to 4 weeks
Serrated polyps per colonoscopy
Proportion of participants with at least one serrated polyp; mean number of sessile serrated lesions per colonoscopy.
Measured: From colonoscopy until histopathology results are available, up to 4 weeks
Total Procedure Time
Total time from endoscope insertion to endoscope withdrawal per procedure.
Measured: During colonoscopy (single procedure)
Withdrawal Time
Total withdrawal time from caecum to endoscope removal.
Measured: During colonoscopy (single procedure)
Need for early repeat colonoscopy due to inadequate preparation
Proportion of participants for whom an early repeat colonoscopy is booked or performed because of inadequate bowel preparation, ascertained by structured medical record review.
Measured: 7 days after colonoscopy
Immediate and delayed adverse events
Immediate adverse events recorded in the recovery area, and delayed adverse events within 7 days ascertained by structured medical record review, including emergency department presentations, unplanned admissions, abdominal pain requiring medical evaluation, bleeding and perforation.
Measured: From colonoscopy to 7 days after the procedure
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Sep 2026
- Study start1 Nov 2026 (estimated)
- Primary completion1 Nov 2028 (estimated)
- Study completion1 Nov 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Colonic PolypsStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Diagnosis
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 320 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Westmead Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Nicholas Burgess, Westmead Hospital
- Investigators
- Michael J Bourke, MBBS,FRACP, Study director, Westmead Hospita, Endoscopy UnitNicholas G Burgess, MBChB, PhD, FRACP, Principal investigator, Westmead Hospita, Endoscopy Unit
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07813013
- Sponsor's protocol ID
- 2026/PID00505
- Other IDs
- 2026/PID00505
- Acronym
- RIGHT-CLEAN
- Status last verified
- Sep 2026
- First submitted
- 4 Sep 2026
- Last updated
- 24 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified individual participant data underlying the published results will be available, including baseline demographic and clinical characteristics, colonoscopy indication, treatment allocation, operator-recorded and blinded video-review BBPS scores for each colonic segment, lesion detection and histopathology outcomes, procedural metrics (procedure and withdrawal times, sedation, intra-procedural water volume) and adverse events. Procedure videos will not be shared, as they are deleted once blinded review is complete. The linkage file containing identifiers will not be shared.