CClinicalTrials.gg
CompletedNCT03298945Updated Feb 5, 2025Results posted

Comparative Effectiveness of Split-Dose Colonoscopy Bowel Preparation Regimens

A Phase 4 interventional study of Miralax-Gatorade Prep and Golytely in Colorectal Cancer, sponsored by VA Office of Research and Development. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-02-05.

Sponsored by VA Office of Research and Development · Phase 4, Interventional, and Health services research

Phase
Phase 4
Study type
Interventional
Enrollment
2,239
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

From the patients' perspective, the most formidable part of the colonoscopy experience is the process of bowel cleansing. A poorly tolerated bowel preparation regimen often leads to incompletion of scheduled colonoscopies which in turn undermines the effectiveness of colonoscopy, increases cost, and decreases patient satisfaction. The current standard bowel preparation in the VA is of larger volume and less palatable than another commonly used bowel preparation regimen. The investigators propose to compare these two commonly used bowel preparations with respect to the overall completion rate of scheduled colonoscopies in a real-world VA practice setting. The results of the study can be immediately applied to maximize the effectiveness of colonoscopy and increase patient satisfaction in the VA.

Read the detailed description

Anticipated Impacts on Veterans Health Care: by identifying a colonoscopy bowel preparation regimen which is the most effective in real-world VA practice and can be immediately implemented on a VA-wide scale, the proposed study will maximize the effectiveness of colonoscopy in reducing colorectal cancer (CRC) risk among Veterans, increase Veteran satisfaction, and reduce VA healthcare cost. Background: CRC is a leading cause of cancer-related death among Veterans. Colonoscopy can effectively reduce CRC incidence and mortality. However, non-adherence to screening colonoscopy substantially undermines this benefit. Existing evidence indicates that a disagreeable bowel preparation is a leading barrier to completing a colonoscopy from the patients' perspective. The taste and the volume of the bowel preparation determine patient tolerability and compliance to the preparation instructions, which in turn affects the incompletion (e.g., cancellation/no-show/reschedule) rate of scheduled colonoscopies as well as the effectiveness of the completed colonoscopies and patient satisfaction. The two most commonly used preparations currently in the US are the split-dose 4L polyethylene glycol (PEG) and the split-dose 2L MiraLAX/Gatorade preparations. While a high-volume regimen may in theory be more effective than a lower volume one, it may be associated with lower tolerability and adherence in real-world practice. Three small trials have compared these two preparations. However, data from these explanatory trials cannot inform policy decisions because they were conducted under artificial conditions, restricted among narrow patient populations, and most importantly not designed to capture the full impact of bowel preparation on the completion rate or effectiveness of colonoscopy. To address this critical knowledge gap, the investigators are proposing a pragmatic trial to determine the optimal split-dose bowel preparation in the general Veteran population. Objectives: to compare the real-world effectiveness of the two most commonly used split-dose colonoscopy bowel preparation regimens in the US (i.e., 4L PEG and 2L MiraLAX/Gatorade) with respect to the completion rate of scheduled colonoscopies, adenoma detection rate and secondarily preparation quality, cancellation/no-show rate and patient-oriented outcomes (e.g., willingness to repeat the preparation).

02

Conditions studied

  • Colorectal Cancer

Keywords

  • colonoscopy
  • colorectal cancer
  • bowel preparation regimen
  • pragmatic trial
03

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • > 18 years of age, and
  • being scheduled for outpatient elective screening, surveillance or diagnostic colonoscopies, and
  • the provider ordering the colonoscopy giving permission to enroll the patient.

Exclusion criteria

Exclusion Criteria:

  • Patients who are \<18 years
  • undergoing inpatient colonoscopy
  • those with contra-indications to receiving the standard 4L PEG-ELS colonoscopy bowel preparation (e.g., allergy to PEG) will be excluded
  • Those with a preference for a specific bowel preparation will be excluded.

    • The investigators are excluding inpatient colonoscopies because they account for a very small fraction of the total colonoscopies performed.
    • Also, inpatient colonoscopies are often performed for urgent reasons such that rapid bowel preparation procedures are followed.
  • In addition, because the objective of inpatient colonoscopy is often not to look for small polyps, the threshold for "adequate" bowel preparation quality might be different from that for outpatient procedures.
  • In addition, for patients undergoing more than 1 colonoscopy during the study period, only their first colonoscopy will be included in the primary analysis.
  • Patients who are undergoing a repeat colonoscopy for to a recent inadequate colonoscopy examination with poor bowel preparation will be excluded.
04

Study design

Phase
Phase 4
Primary purpose
Health services research
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Single (Outcomes assessor)
Enrollment
2,239 participants (actual)

Study arms

  • Active comparator
    Golytely

    4-L split-dose Golytely bowel prep

    Drug: Golytely

  • Experimental
    Miralax-Gatorade prep

    2-L split-dose Miralax-Gatorade bowel prep

    Drug: Miralax-Gatorade Prep

Interventions

  • DrugMiralax-Gatorade Prep

    2-L split-dose Miralax-Gatorade bowel prep for colonoscopy

  • DrugGolytely

    4-L split dose Golytely is the current standard prep at the VA

05

What researchers measure

Primary outcomes

  1. Colonoscopy Completion Rate

    The completion rate of scheduled colonoscopy will be defined as the proportion of patients who show up for their scheduled colonoscopy and have endoscopist-rated "adequate" bowel preparation quality, among those scheduled for a colonoscopy.

    Time frame: This outcome is determined within 1 month after colonoscopy

  2. Population Level Adenoma Detection Rate (ADR)

    the ADR is estimated as the proportion of patients with at least one adenoma detected among all patients scheduled for colonoscopy.

    Time frame: within 1 month of colonoscopy

Secondary outcomes

  1. Cancellation or No-show in Each Bowel Prep Arm

    The proportion of patients who cancel or no-show in each group.

    Time frame: within 1 month after colonoscopy

  2. Adequate Bowel Prep Quality

    this is a binary indictor based on endoscopist rating of excellent or good quality bowel preparation

    Time frame: within 1 month after the colonoscopy

Other outcomes

  1. Patients With Inadequate Bowel Preparation Who Are Recommended to Have Earlier-than-usual Follow-up Colonoscopy

    patients with inadequate bowel preparation who are recommended to have earlier-than-usual follow-up colonoscopy

    Time frame: within 1 month after colonoscopy

  2. Hyponatremia

    Hyponatremia

    Time frame: within 6 months after colonoscopy

  3. Renal Failure

    renal failure documented in CPRS

    Time frame: within 6 months of colonoscopy

06

Results

Posted Jan 22, 2025

Participant flow

Participants were recruited based on referral from the primary care providers ordering colonoscopy at the Corporal Michael J. Crescenz Department of Veterans Affairs Medical Center. The first participant was enrolled on December 13, 2018, and the last participant was enrolled on January 27, 2023.

Participant flow — Overall Study
MilestoneGolytelyMiralax-Gatorade Prep
Started11391100
Completed11391100
Not completed00

Outcome measures

PrimaryColonoscopy Completion Rate

The completion rate of scheduled colonoscopy will be defined as the proportion of patients who show up for their scheduled colonoscopy and have endoscopist-rated "adequate" bowel preparation quality, among those scheduled for a colonoscopy.

Time frame:
This outcome is determined within 1 month after colonoscopy
Reported as:
Count of participants · Participants
Colonoscopy Completion Rate
ParticipantsGolytelyMiralax-Gatorade Prep
Colonoscopy Completion Rate591600
PrimaryPopulation Level Adenoma Detection Rate (ADR)

the ADR is estimated as the proportion of patients with at least one adenoma detected among all patients scheduled for colonoscopy.

Time frame:
within 1 month of colonoscopy
Reported as:
Count of participants · Participants
Population Level Adenoma Detection Rate (ADR)
ParticipantsGolytelyMiralax-Gatorade Prep
Population Level Adenoma Detection Rate (ADR)383364
SecondaryCancellation or No-show in Each Bowel Prep Arm

The proportion of patients who cancel or no-show in each group.

Time frame:
within 1 month after colonoscopy
Reported as:
Count of participants · Participants
Cancellation or No-show in Each Bowel Prep Arm
ParticipantsGolytelyMiralax-Gatorade Prep
Cancellation or No-show in Each Bowel Prep Arm358330
SecondaryAdequate Bowel Prep Quality

this is a binary indictor based on endoscopist rating of excellent or good quality bowel preparation

Time frame:
within 1 month after the colonoscopy

Results for this outcome have not been posted.

Other pre-specifiedPatients With Inadequate Bowel Preparation Who Are Recommended to Have Earlier-than-usual Follow-up Colonoscopy

patients with inadequate bowel preparation who are recommended to have earlier-than-usual follow-up colonoscopy

Time frame:
within 1 month after colonoscopy

Results for this outcome have not been posted.

Other pre-specifiedHyponatremia

Hyponatremia

Time frame:
within 6 months after colonoscopy

Results for this outcome have not been posted.

Other pre-specifiedRenal Failure

renal failure documented in CPRS

Time frame:
within 6 months of colonoscopy

Results for this outcome have not been posted.

Adverse events

Collected over 6 months. Non-serious events are listed at a 3% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Golytely7/1,139 (0.6%)6/1,139 (0.5%)0/1,139 (0%)
Miralax-Gatorade Prep4/1,100 (0.4%)5/1,100 (0.5%)0/1,100 (0%)
Most frequent serious events
Most frequent serious events
EventGolytelyMiralax-Gatorade Prep
Colorectal cancer diagnosed on colonoscopyNeoplasms benign, malignant and unspecified (incl cysts and polyps)2/11395/1100
Hospitalization for mania and psychosisPsychiatric disorders1/11390/1100
Hospitalization for lung surgeryRespiratory, thoracic and mediastinal disorders1/11390/1100
Hospitalization for respiratory distressRespiratory, thoracic and mediastinal disorders1/11390/1100
Hospitalization for DKAEndocrine disorders1/11390/1100

Baseline characteristics

Age, Continuous
Age, Continuous(years)GolytelyMiralax-Gatorade PrepTotal
Mean62.6 ± 9.762.6 ± 9.562.6 ± 7.2
Sex: Female, Male
Sex: Female, Male(Participants)GolytelyMiralax-Gatorade PrepTotal
Female107113220
Male10329872019
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)GolytelyMiralax-Gatorade PrepTotal
Hispanic or Latino364884
Not Hispanic or Latino107410202094
Unknown or Not Reported293261
Race (NIH/OMB)
Race (NIH/OMB)(Participants)GolytelyMiralax-Gatorade PrepTotal
American Indian or Alaska Native000
Asian101828
Native Hawaiian or Other Pacific Islander91827
Black or African American407397804
White6706311301
More than one race000
Unknown or Not Reported433679
Body mass index group
Body mass index group(Participants)GolytelyMiralax-Gatorade PrepTotal
<18.5 kg/m^210919
18.5 to 24.9 kg/m^2198175373
25 to 29.9 kg/m^2395368763
30 or more kg/m^25275431070
Missing9514
Smoking status
Smoking status(Participants)GolytelyMiralax-Gatorade PrepTotal
Never smoker347339686
Former smoker455430885
Current smoker327306633
Missing102535
Alcohol use disorder
Alcohol use disorder(Participants)GolytelyMiralax-Gatorade PrepTotal
Count of participants108116224
Diabetes mellitus
Diabetes mellitus(Participants)GolytelyMiralax-Gatorade PrepTotal
Count of participants334329663

3 further baseline measures are reported on the registry.

07

Study locations

1 site
  • Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
    Philadelphia, Pennsylvania 19104-4551, United States
08

References and documents

Publications

  • Comparative Effectiveness of Split-Dose Colonoscopy Bowel Preparation Regimens: A Pragmatic Randomized Controlled Trial Yang, Yu-Xiao, Dawei Xie, Raphael Rivero, Michael W. Bond, Jibreel Damisa, Qiao Lu, Nabeel H. Khan Gastroenterology, 2024-05-18, Volume 166, Issue 5, Pages S-353-S-353

Study documents

  • Protocol and statistical analysis plan · Jun 17, 2018

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

09

Registry details

Key details

Study ID
NCT03298945
Lead sponsor
VA Office of Research and Development
Responsible party
Sponsor
First posted
Oct 2, 2017
Start date
Dec 13, 2018
Primary completion
Dec 30, 2023
Completion
Jun 30, 2024
Results posted
Jan 22, 2025
Last update
Feb 5, 2025

Study contacts

Yu-Xiao Yang, MD MSCE
principal investigator · Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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