Experience Using Ustekinumab in Pediatric Patients With Medically Refractory Crohn Disease.

Introduction: Ustekinumab (UST), a human monoclonal antibody against interleukin-12 and 23, is approved to treat adult patients with psoriasis or Crohn disease (CD). Outcomes data for off-label use in pediatric patients with CD are limited.

Aim: We conducted a retrospective cohort study to analyze the long-term efficacy of UST, including dose adjustments, in the treatment of pediatric patients with medically refractory CD. Adverse events were documented.

Methods: We identified 40 pediatric patients with CD treated with UST between January 1, 2016 and December 31, 2019. Electronic medical records were reviewed for demographics, Paris Classification, significant comorbidities, previous CD therapy, adverse events after initiation, and surveillance markers at the time of their first dose and most recent clinic visit. A validated abbreviated pediatric CD activity index (aPCDAI) was used to assess response to therapy.

Results: Thirty-eight pediatric patients with CD, including 34.2% with stricturing or penetrating disease, were analyzed after initiation of treatment with UST. Median age at diagnosis of CD was 12.5 years, and median age at UST induction was 17.2 years. No patients were anti-TNF-naive, and 34.2% were previously exposed to 2 or more anti-TNF agents. At time of last follow-up, 84.2% of patients remained on UST for a median duration on UST of 62.1 weeks, and 60.5% achieved clinical remission. Patients had significant improvement in aPCDAI scores, clinical remission rates, albumin, and hematocrit, and 89.5% of patients had no significant adverse events. Similar results were observed among those who required dose adjustment, including 61.1% achieving clinical remission, and among those with perianal disease, including 38.5% achieving clinical remission.

Conclusions: Our data suggest that, within our cohort of pediatric patients with CD, UST has long-term efficacy with no observed safety concerns. Dose adjustment may be helpful in achieving clinical remission.