Design of a phase 3, randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of prucalopride in pediatric patients with functional constipation.

Background: A previous phase 3 trial of prucalopride in pediatric patients (6 months-18 years old) with functional constipation (FC) demonstrated no efficacy versus placebo. We designed an additional phase 3 trial to further assess the efficacy, long-term safety and tolerability of prucalopride in children and adolescents. Methods: This multicenter trial (ClinicalTrials.gov identifier: NCT04759833; EudraCT number: 2022-003221-22) comprises a 12-week, randomized, double-blind, placebo-controlled phase, followed by a 36-week, double-blind, safety extension phase. Approximately 240 toilet-trained patients aged 3-17 years will be randomized 1:1:1 to receive low- (0.04 mg/kg) or high-dose (0.08 mg/kg) prucalopride, or placebo once daily. Fifteen non-toilet-trained patients ≥6 months old with FC will be included in an exploratory efficacy and safety analysis. Discussion: The efficacy endpoints used in this study will differ from those used in adults and in the previous pediatric phase 3 trial; they have been adapted to be more suitable for a wider age range of pediatric patients. Both study phases will be longer than in the previous pediatric study, providing a longer time period in which to assess the efficacy and safety of prucalopride. Study participants will be identified using the modified Rome IV criteria for FC, instead of the Rome III criteria, and non-toilet-trained patients will be included, which will broaden the population of pediatric patients assessed. Patients will undergo fecal disimpaction before randomization and undergo standardized continuous behavioral therapy throughout the trial. This pediatric study of prucalopride will aim to demonstrate the efficacy and long-term safety of this treatment.