Feasibility and tolerability of reduced-volume oral sulfate solution combined with elobixibat for bowel preparation before colonoscopy: a single-center pilot study.

BACKGROUND

Reducing the volume of bowel preparation may improve patient adherence and tolerability without compromising cleansing efficacy. Oral sulfate solution (OSS) is a low-volume preparation option, and elobixibat, a bile acid transporter inhibitor, may enhance colonic secretion and motility. We evaluated the feasibility, efficacy, safety, and tolerability of a same-day regimen combining elobixibat with OSS.

METHODS

This prospective single-arm pilot study was conducted at Juntendo University Hospital in Japan. Consecutive patients aged 20-64 years scheduled for elective colonoscopy were enrolled between April 2021 and March 2023. Patients received elobixibat (10 mg once daily for 3 days before colonoscopy), followed by same-day OSS using a "stop-when-clear" protocol. The primary outcome was adequate bowel preparation, defined as a total Boston Bowel Preparation Scale (BBPS) score ≥6. Secondary outcomes included OSS volume consumed, adverse events, and patient-reported tolerability assessed by questionnaire.

RESULTS

Twenty-eight patients were analyzed. Adequate bowel preparation was achieved in 96% of patients. BBPS ≥2 were 82% in the right colon, 96% in the transverse colon, and 100% in the left colon. The mean total OSS volume was 771 mL, and 57% of patients completed preparation with ≤720 mL. No serious adverse events were observed. Most patients reported acceptable palatability (82%) and manageable volume (100%). Among those with prior colonoscopy experience, 75% preferred this regimen and 86% indicated willingness to use it again.

CONCLUSIONS

A same-day regimen combining elobixibat with OSS demonstrated favorable feasibility, efficacy, and tolerability. Reduced OSS volume may be achievable in selected patients. However, these findings are limited to a relatively low-risk, non-elderly population and should be confirmed in larger comparative studies.