A Pilot Study of Commercially Available Bowel Preparation Regimens Packaged and Ingested Via Vegan Capsules (CLEAR-CAP)

A Pilot Study of Commercially Available Bowel Preparation Regimens Packaged and Ingested Via Vegan Capsules: Safety, Tolerability, Feasibility, and Preliminary Cleansing Effectiveness

The goal of this clinical trial is to learn whether bowel preparation powders used before colonoscopy can be taken as capsules instead of being mixed and drunk as a liquid. Bowel preparation is the medicine people take to clean the bowel before a colonoscopy.

This study will include adults aged 18 to 75 years who are already scheduled for an outpatient colonoscopy and who have had a colonoscopy before.

The main questions this study aims to answer are:

1. Can participants swallow and complete a large number of bowel preparation capsules with the required clear fluids?
2. Can the capsules be prepared accurately and practically by a pharmacy or by participants at home?
3. Is the capsule-based bowel preparation safe and well tolerated?
4. Does the capsule-based bowel preparation clean the bowel well enough for colonoscopy?

Participants will take approved bowel preparation products, Pico-Salax or Bi-PegLyte, in vegan hydroxypropyl methylcellulose capsules. They will take the capsules with clear fluids using a split-dose schedule before colonoscopy.

The study will happen in three parts. First, researchers will test two capsule sizes using Pico-Salax capsules prepared by a partner pharmacy. Then, researchers will test Bi-PegLyte capsules using the capsule size selected from the first part. Finally, some participants will prepare the capsules themselves at home using study instructions and materials.

Researchers will measure how many capsules and how much fluid participants complete, symptoms during preparation, safety blood tests, participant satisfaction, and bowel cleanliness during colonoscopy.

Study Overview

• Status: Not yet recruiting
• Conditions: Tolerance; Lower Gastrointestinal Disorder
• Intervention / Treatment: Drug: Sodium picosulfate, magnesium oxide, and citric acid capsules; Drug: Polyethylene glycol 3350 with electrolytes capsules

Detailed Description

This is a prospective, single-site, open-label, sequential, non-randomized pilot feasibility study of capsule-based bowel preparation before colonoscopy.

The study will evaluate whether approved commercially available bowel preparation powders can be administered in vegan hydroxypropyl methylcellulose capsules instead of being mixed into a liquid solution before ingestion. The approved products used in this study are Pico-Salax and Bi-PegLyte. The active products, total approved dose, oral route, required clear-fluid intake, and split-dose timing will be preserved. The investigational aspect is the capsule-based method of administration.

The rationale for the study is that many people find liquid bowel preparation difficult to complete because of taste, texture, nausea, and the amount of liquid required. Capsule-based administration may reduce exposure to unpleasant taste and mouthfeel while maintaining the intended bowel cleansing effect, provided participants drink the required clear fluids.

The study will enroll adults aged 18 to 75 years who are scheduled for elective outpatient colonoscopy for screening, surveillance, or diagnostic indications and who have previously completed a conventional bowel preparation. Participants must be able to swallow solids, liquids, and pills without difficulty.

The study will proceed in three sequential parts:

In Part I, approximately 40 participants will receive Pico-Salax powder packaged in HPMC capsules prepared by a partner pharmacy. Twenty participants will receive size "000" capsules and 20 participants will receive size "00" capsules. This part will assess capsule ingestion completion, clear-fluid completion, swallowing acceptability, tolerability, safety, and bowel cleansing quality for the two capsule sizes.

After Part I, the study team will review tolerability, swallowing difficulty, capsule and fluid completion, safety findings, and bowel cleansing results. One capsule size will be selected for use in the later parts of the study.

In Part II, approximately 20 participants will receive Bi-PegLyte powder packaged in HPMC capsules prepared by the partner pharmacy using the capsule size selected after Part I. This part will assess whether a higher capsule-burden preparation is feasible and tolerated.

In Part III, approximately 20 participants will prepare the capsules themselves at home using study-supplied materials and written instructions. Ten participants will prepare Pico-Salax capsules and 10 participants will prepare Bi-PegLyte capsules. This part will assess whether participant-led home capsule preparation is practical, acceptable, and safe.

Across all parts, participants will take the capsule-based bowel preparation using a split-dose schedule before colonoscopy. Participants will drink the required clear fluids according to the study instructions. Participants assigned to Bi-PegLyte will take the bisacodyl tablets separately according to the usual regimen.

The primary outcomes are tolerability and feasibility. These include the proportion of participants who can ingest at least 80% of the prescribed capsules within the study dosing window, the proportion who complete the required clear-fluid intake, and the proportion who complete bowel preparation without stopping early because of capsule burden or swallowing difficulty. In the home-preparation part, feasibility will also include the proportion of participants who prepare at least 80% of the required capsules, preparation time, capsule count reconciliation, and participant-reported difficulty and confidence.

Secondary outcomes include participant-reported symptoms, adverse events, serious adverse events, clinically significant changes in electrolytes or creatinine, dehydration, emergency department presentation or hospitalization, and bowel cleansing quality at colonoscopy. Bowel cleansing will be assessed using the Boston Bowel Preparation Scale. Adequate bowel preparation is defined as a total score of at least 6 with no segment score below 2.

This pilot study is descriptive and is not designed for formal hypothesis testing. The results will help determine whether capsule-based bowel preparation is feasible, acceptable, and safe enough to support a future randomized controlled trial comparing capsule-based bowel preparation with standard liquid bowel preparation.

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Early Phase 1

Contacts and Locations

• Study Contact: Name: Sanjay K Murthy, MD; Phone Number: 73542 613-737-8899; Email: smurthy@toh.ca
• Study Contact Backup: Name: Abbey Corson, MSc; Phone Number: 73542 613-737-8899; Email: acorson@ohri.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Age 18 to 75 years.
• Scheduled for elective outpatient colonoscopy for a screening, surveillance, or diagnostic indication.
• Has previously undergone colonoscopy using a conventional bowel preparation solution, without requiring repeat colonoscopy because of poor bowel preparation.
• Able to provide informed consent.
• Willing and able to comply with study procedures, including timed dosing, required clear-fluid intake, and capsule preparation procedures for participants enrolled in Part III.
• Able to swallow solids, liquids, and pills without difficulty.

Exclusion Criteria:

• Higher risk for clinically significant fluid or electrolyte shifts, including chronic renal impairment, severely reduced renal function, congestive cardiac failure, unstable cardiovascular disease, or any other condition in which large-volume fluid intake or rapid catharsis may be unsafe.
• Baseline clinically significant electrolyte abnormalities.
• Diabetes mellitus, gastroparesis, gastric retention, intestinal dysmotility, or any other condition that may impair gastric emptying, gastrointestinal transit, mixing, dissolution, or passage of the bowel preparation.
• Current use of medications that may impair gastrointestinal motility or safe bowel preparation completion, including opioid medications, anticholinergic medications, or glucagon-like peptide-1 receptor agonists.
• Known or suspected gastrointestinal obstruction, bowel obstruction, ileus, bowel perforation, gastrointestinal perforation, or any condition associated with increased risk of obstruction or perforation.
• Acute abdominal or gastrointestinal condition in which bowel preparation may be unsafe, including acute surgical abdomen, acute appendicitis, gastroenteritis, diverticulitis, toxic colitis, toxic megacolon, severe colitis requiring urgent care, or another acute inflammatory, infectious, or structural gastrointestinal condition judged by the investigator to make participation unsafe.
• Known gastrointestinal ulceration or clinically significant active gastrointestinal bleeding, including unexplained rectal bleeding.
• Active nausea or vomiting at screening or before bowel preparation administration that, in the opinion of the investigator, would interfere with safe ingestion of the assigned capsule-based bowel preparation regimen.
• Emergency colonoscopy, including colonoscopy for lower gastrointestinal bleeding or any clinical condition requiring urgent endoscopic evaluation that would not allow adherence to the study bowel preparation protocol.
• Known hypersensitivity, allergy, or intolerance to Bi-PegLyte, Pico-Salax, bisacodyl, polyethylene glycol, sodium picosulfate, magnesium oxide, citric acid, electrolytes contained in the formulations, HPMC/hypromellose capsules, or any ingredient in the formulation or product container.
• Pregnancy or known or suspected pregnancy at screening or before bowel preparation administration.
• Capsule-specific feasibility or safety concern, including dysphagia, esophageal dysmotility, achalasia, esophageal stricture, high risk of aspiration, anatomical abnormality affecting swallowing, or any condition in which swallowing a large number of capsules is considered unsafe.
• Practical or adherence-related concern, including inability to follow timed dosing instructions, inability to comply with the required clear-fluid intake, lack of reliable contact, or anticipated nonadherence to study procedures.
• For Part III only: inability or unwillingness to self-prepare capsules using study-provided materials and instructions; inadequate manual dexterity or vision to prepare capsules safely and accurately; inability to complete the teach-back procedure, if required; or unwillingness to follow the standardized home preparation workflow, including use only of study-supplied materials, preparation within the defined time window, and storage as instructed.
• Any contraindication listed in the product monograph for Bi-PegLyte or Pico-Salax.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Capsule-Based Bowel Preparation; Participants receive capsule-based bowel preparation before elective outpatient colonoscopy. The study is conducted sequentially in three parts: Part I evaluates centrally prepared Pico-Salax capsules using size "000" and size "00" HPMC capsules; Part II evaluates centrally prepared Bi-PegLyte capsules using the capsule size selected after Part I; and Part III evaluates participant-prepared Pico-Salax or Bi-PegLyte capsules at home using study-supplied materials and instructions. All regimens use approved marketed bowel preparation products at their approved dose with required clear-fluid intake and split-dose timing.

Drug: Sodium picosulfate, magnesium oxide, and citric acid capsules; Pico-Salax powder for oral solution, containing sodium picosulfate, magnesium oxide, and citric acid, is transferred into vegan hydroxypropyl methylcellulose capsules and administered orally with required clear fluids using a split-dose bowel preparation schedule before colonoscopy. In Part I, Pico-Salax capsules are centrally prepared using size "000" and size "00" capsules. In Part III, participants prepare Pico-Salax capsules at home using the capsule size selected after Part I and study-supplied materials and instructions.; Drug: Polyethylene glycol 3350 with electrolytes capsules; Bi-PegLyte powder, containing polyethylene glycol 3350 with electrolytes, is transferred into vegan hydroxypropyl methylcellulose capsules and administered orally with required clear fluids using a split-dose bowel preparation schedule before colonoscopy. Bisacodyl tablets included in the approved Bi-PegLyte regimen are taken separately according to the usual regimen. In Part II, Bi-PegLyte capsules are centrally prepared using the capsule size selected after Part I. In Part III, participants prepare Bi-PegLyte capsules at home using study-supplied materials and instructions.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Capsule ingestion completion	Proportion of participants who ingest at least 80% of the prescribed bowel preparation capsules within the protocol-defined dosing window.	From first capsule ingestion through colonoscopy, approximately 24 hours
Clear-fluid intake completion	Proportion of participants who complete the required clear-fluid intake according to the protocol-defined bowel preparation schedule.	From first capsule ingestion through colonoscopy, approximately 24 hours
Completion without premature discontinuation due to capsule burden or swallowing difficulty	Proportion of participants who complete the capsule-based bowel preparation without stopping early because of capsule burden, swallowing difficulty, or intolerance related to capsule ingestion.	From first capsule ingestion through colonoscopy, approximately 24 hours
Capsule preparation feasibility	Feasibility of capsule preparation, including the proportion of participants in Part III who prepare at least 80% of required capsules, capsule count reconciliation relative to expected dose, time required for capsule preparation, and participant-reported difficulty and confidence in preparation accuracy.	From capsule preparation through colonoscopy, up to 7 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Participant-reported swallowing difficulty	Participant-reported swallowing difficulty during capsule-based bowel preparation, assessed using the study-specific tolerability questionnaire. Swallowing difficulty is scored on a 5-point Likert scale from 1 to 5, where higher scores indicate greater swallowing difficulty.	From first capsule ingestion through pre-procedure assessment on the day of colonoscopy, approximately 24 hours
Treatment-emergent adverse events	Incidence and severity of treatment-emergent adverse events, including nausea, vomiting, abdominal pain, bloating, dizziness, dehydration, and other adverse events reported after capsule ingestion.	From first capsule ingestion through pre-procedure assessment on the day of colonoscopy, approximately 24 hours
Serious adverse events	Incidence of serious adverse events, including events requiring emergency department presentation, hospitalization, or urgent medical intervention.	From first capsule ingestion through 24 hours after colonoscopy
Change in serum electrolytes and creatinine	Change from baseline to post-bowel-preparation assessment in serum electrolytes and creatinine, including sodium, potassium, chloride, bicarbonate or total carbon dioxide, urea, and creatinine.	Baseline within 1 week before bowel preparation and repeat assessment on the day of colonoscopy
Adequate bowel preparation by Boston Bowel Preparation Scale	Proportion of participants with adequate bowel preparation, defined as Boston Bowel Preparation Scale total score of at least 6 with no individual colon segment score below 2.	During colonoscopy on Day 0
Total Boston Bowel Preparation Scale score	Total Boston Bowel Preparation Scale score recorded during colonoscopy. Scores range from 0 to 9, with higher scores indicating better bowel cleansing.	During colonoscopy on Day 0
Cecal intubation rate	Proportion of participants in whom cecal intubation is achieved during colonoscopy.	During colonoscopy on Day 0
Need for rescue measures or early repeat colonoscopy	Proportion of participants requiring rescue bowel preparation measures, additional intraprocedural lavage due to inadequate cleansing, or recommendation for early repeat colonoscopy due to inadequate bowel preparation.	During colonoscopy on Day 0
Participant-reported nausea	Participant-reported nausea during capsule-based bowel preparation, assessed using the study-specific tolerability questionnaire. Nausea is scored on a 5-point Likert scale from 1 to 5, where higher scores indicate worse nausea.	From first capsule ingestion through pre-procedure assessment on the day of colonoscopy, approximately 24 hours
Participant-reported overall tolerability	Participant-reported overall tolerability of capsule-based bowel preparation, assessed using the study-specific tolerability questionnaire. Overall tolerability is scored on a 5-point Likert scale from 1 to 5, where higher scores indicate better tolerability.	From first capsule ingestion through pre-procedure assessment on the day of colonoscopy, approximately 24 hours
Participant-reported vomiting	Vomiting is assessed using the study-specific tolerability questionnaire. Vomiting is scored on a 5-point Likert scale from 1 to 5, where higher scores indicate worse vomiting.	From first capsule ingestion through pre-procedure assessment on the day of colonoscopy, approximately 24 hours
Participant-reported abdominal discomfort	Abdominal discomfort is assessed using the study-specific tolerability questionnaire. Abdominal discomfort is scored on a 5-point Likert scale from 1 to 5, where higher scores indicate worse abdominal discomfort.	From first capsule ingestion through pre-procedure assessment on the day of colonoscopy, approximately 24 hours
Participant-reported dizziness	Dizziness is assessed using the study-specific tolerability questionnaire. Dizziness is scored on a 5-point Likert scale from 1 to 5, where higher scores indicate worse dizziness.	From first capsule ingestion through pre-procedure assessment on the day of colonoscopy, approximately 24 hours

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Global satisfaction score for capsule-based bowel preparation	Participant-reported global satisfaction with capsule-based bowel preparation, assessed using the study-specific satisfaction questionnaire. Global satisfaction is scored from 0 to 10, where higher scores indicate greater satisfaction.	From colonoscopy visit through post-procedure follow-up, within 24 to 72 hours after colonoscopy
Participant-reported difficulty with home capsule preparation	Among participants in Part III, participant-reported difficulty with preparing bowel preparation capsules at home, assessed using the study-specific questionnaire. Difficulty is scored on a 5-point Likert scale from 1 to 5, where higher scores indicate greater difficulty.	From home capsule preparation through post-procedure follow-up, within 24 to 72 hours after colonoscopy
Willingness to repeat capsule-based bowel preparation	Proportion of participants who report that they would be willing to use capsule-based bowel preparation again for a future colonoscopy.	From colonoscopy visit through post-procedure follow-up, within 24 to 72 hours after colonoscopy
Preference for capsule-based bowel preparation compared with prior liquid bowel preparation	Proportion of participants who report preferring capsule-based bowel preparation compared with their prior conventional liquid bowel preparation.	From colonoscopy visit through post-procedure follow-up, within 24 to 72 hours after colonoscopy
Participant-reported confidence in home capsule preparation accuracy	Among participants in Part III, participant-reported confidence in having prepared the bowel preparation capsules accurately at home, assessed using the study-specific questionnaire. Confidence is scored on a 5-point Likert scale from 1 to 5, where higher scores indicate greater confidence.	From home capsule preparation through post-procedure follow-up, within 24 to 72 hours after colonoscopy
Time required for home capsule preparation	Among participants in Part III, time in minutes required to prepare the bowel preparation capsules at home.	During home capsule preparation before colonoscopy, up to 7 days
Willingness to prepare bowel preparation capsules at home again	Proportion of participants in Part III who report willingness to prepare bowel preparation capsules at home again for a future colonoscopy.	Within 24 to 72 hours after colonoscopy

Collaborators and Investigators

• Sponsor: Ottawa Hospital Research Institute

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): August 1, 2027
• Study Completion (Estimated): December 30, 2027

Study Registration Dates

• First Submitted: July 2, 2026
• First Submitted That Met QC Criteria: July 10, 2026
• First Posted (Actual): July 14, 2026

Study Record Updates

• Last Update Posted (Actual): July 14, 2026
• Last Update Submitted That Met QC Criteria: July 10, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Colonoscopy; Bowel preparation
• Additional Relevant MeSH Terms: Organic Chemicals; Acids, Acyclic; Carboxylic Acids; Inorganic Chemicals; Oxides; Oxygen Compounds; Citrates; Tricarboxylic Acids; Magnesium Compounds; Magnesium Oxide; Citric Acid; picosulfate sodium; polyethylene glycol 3350; Electrolytes
• Other Study ID Numbers: CLEAR-CAP

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: The plan for sharing individual participant data has not yet been determined. This is a small pilot feasibility study, and any future sharing of de-identified participant-level data would require review and approval by the sponsor-investigator and institutional policies, and would be conducted in accordance with applicable privacy, ethics, and regulatory requirements.

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