Comparison of the efficacy and safety of an oral sulfate solution and 3-L polyethylene glycol on bowel preparation before colonoscopy: a phase III multicenter randomized controlled trial

Background and Aims: Adequate bowel preparation is crucial for clear mucosal visualization during colonoscopy. We aimed to comprehensively compare oral sulfate solution (OSS) and 3-L split-dose polyethylene glycol (PEG) for bowel preparation before colonoscopy. Methods: This randomized, active-controlled, noninferiority study was performed in 10 medical centers. Eligible subjects were enrolled to receive OSS or 3-L PEG in a split-dose regimen. The quality of bowel preparation, adverse reactions, and acceptability were evaluated. The quality of bowel preparation was evaluated using the Boston Bowel Preparation Scale. Safety was evaluated by adverse reactions. The study population was divided into the full analysis set (FAS), the safety set, the modified FAS (mFAS), and the per-protocol set (PPS). Results: Three hundred forty-eight potentially eligible subjects were enrolled. Three hundred forty-four subjects were included in the FAS and safety set, 340 subjects were included in the mFAS, and 328 subjects were included in the PPS. Adequate bowel preparation of the OSS was not inferior to 3-L PEG in the mFAS (98.22% vs 97.66%) and the PPS (98.17% vs 98.78%). There was no significant difference in acceptability between the 2 groups (94.74% vs 94.80%, P = .9798). Overall adverse reactions were similar (50.88% vs 44.51%, P = .2370) between the 2 groups. Conclusions: The split-dose OSS regimen was not inferior to the split-dose 3-L PEG regimen for the quality of bowel preparation in a Chinese adult population. The safety and acceptability of the 2 groups were similar.