STEP-CD study: ustekinumab use in paediatric Crohn's disease-a multicentre retrospective study from paediatric IBD Porto group of ESPGHAN.

Ustekinumab is an effective therapy for adult Crohn's disease (CD), but data in paediatric CD patients are scarce. The aim of the study was to describe the real-life effectiveness and safety of ustekinumab in paediatric CD. This is a multicentre review of children with Crohn's disease treated with ustekinumab. The aim of our study was to describe the effectiveness and safety of ustekinumab in paediatric real-life practice. This is a study of the Paediatric IBD (inflammatory bowel disease) Porto group of ESPGHAN. Corticosteroid (CS)- and exclusive enteral nutrition (EEN)-free remission, defined as weighted Paediatric Crohn's Disease Activity Index (wPCDAI) < 12.5, and physician global assessment (PGA) were determined at weeks 12 and 52. A total of 101 children were included at a median age of 15.4 years (IQR 12.7-17.2) with a median follow-up of 7.4 months (IQR 5.6-11.8). Ninety-nine percent had received prior anti-TNF, 63% ≥ 2 anti-TNFα therapies and 22% vedolizumab. Baseline median wPCDAI was 39 (IQR 25-57.5) (71 (70%) patients with moderate-severe activity). Weeks 12 and 52 CS- and EEN-free remission were both 40.5%. Clinical response at week 6, iv induction route and older age at onset of ustekinumab treatment were predictive factors associated with clinical remission at week 12. Seven minor adverse events probably related to ustekinumab were reported. One patient died from an unrelated cause.    Conclusion: Our results suggest that ustekinumab is effective and safe in children with chronically active or refractory CD. What is Known: • Ustekinumab is an effective therapy for adult moderate to severe Crohn's disease (CD). • Off-label use of ustekinumab in children is increasing especially in anti-TNF refractory CD. What is New: • Is the largest cohort of real-world use of ustekinumab in paediatric CD to date. • Clinical response at week 6, iv induction and older age at onset of ustekinumab were predictive factors associated with clinical response at week 12.