A Pilot Study of Commercially Available Bowel Preparation Regimens Packaged and Ingested Via Vegan Capsules

Overview

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.

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.