Phase III Randomized Non-Inferiority Study of OSS Versus PEG + Electrolyte Colonoscopy Preparation in Adolescents

Many protocols and preparations are used for bowel cleansing before pediatric colonoscopy but few are based on scientific evidence. We evaluated efficacy, safety, tolerability, and patient preference of oral sulfate solution (OSS) at 75% of the adult dose versus polyethylene glycol (PEG)-electrolyte solution in adolescents presenting for diagnostic colonoscopy. METHODS: Phase III, randomized, evaluator-blinded, non-inferiority study of OSS and PEG in adolescents aged 12–17 years. OSS and PEG were administered in 2 doses on the day before colonoscopy. Primary endpoint included proportion of patients with successful overall preparation (4-point scale). Secondary endpoints included overall and segmental bowel cleansing (Boston Bowel Preparation Scale; BBPS), completed colonoscopies, duration of examination, time to cecal intubation, proportion of nasogastric tubes (NGTs), adverse events (AEs) and acceptability. RESULTS: Successful cleansing was achieved in 71.4% and 79.0% of patients receiving OSS and PEG, respectively [adjusted difference −7.61 (95% confidence interval, CI, −18.45 to 3.24); P = 0.0907]. Segmental BBPS score for the left and transverse colon were similar between treatment groups, but better for the right colon with PEG than OSS [2.2 (95% CI, 2.0–2.4) and 1.9 (95% CI, 1.7–2.1), respectively; P = 0.0015]. Significantly fewer OSS patients needed NGT placement to ingest the whole solution [9/125 (7.2%)] than PEG patients [36/116 (31.0%); P < 0.0001]. Treatment acceptability was significantly higher with OSS than PEG (P < 0.0001). Duration of examination, completed colonoscopies, and time to cecal intubation were similar between preparations. Gastrointestinal AEs including nausea, vomiting, abdominal pain, and distension were similar in both groups but more patients receiving PEG had AEs assessed as incapacitating. CONCLUSIONS: Non-inferiority of OSS to PEG was not demonstrated, but OSS was associated with a lower requirement for NGT, better acceptability, and less frequent severe AEs than with PEG.